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SR-08-25-2015-3M City Council Report City Council Regular Meeting: August 25, 2015 Agenda Item: 3.M 1 of 5 To: Mayor and City Council From: Martin Pastucha, Director, Public Works, Civil Engineering Subject: Award Professional Service Agreement for the California Incline Pedestrian Overcrossing and Idaho Trail Project Recommended Action Staff recommends that the City Council: 1. Award RFP# SP2391 to TY Lin International (TY Lin), a California-based company, to provide engineering design services for the California Incline Pedestrian Overcrossing and Idaho Trail Project; 2. Authorize the City Manager to negotiate and execute a professional services agreement with TY Lin in an amount not to exceed $411,827 (including a 10% contingency); 3. Authorize the Director of Public Works to issue any necessary modifications to complete additional work within budget authority. Executive Summary The California Incline Pedestrian Overcrossing (POC) and Idaho Trail (Trail) project addresses the need to replace the POC, and improve the drainage, reduce soil erosion, and improve the maintenance of the Trail. A structural assessment report concluded that the POC is in need of seismic retrofitting, and a portion in need of replacing. The report also made recommendations for drainage improvements that can be made to the Trail to reduce erosion. Staff recommends award of contract to TY Lin to provide engineering design services in an amount not to exceed $411,827. Background Bi-annual inspection reports for the POC performed by the Los Angeles County Department of Public Works (LACDPW), per an agreement with the California Department of Transportation (Caltrans), have consistently given the POC a poor structural rating. These reports have indicated the need for the following: repair the delamination and spalling in the deck surface, patch spalls in the south girder, and replace missing tie wires in the bottom of the pedestrian fence and to rebuild the east 2 of 5 slope to stabilize the staircase and walkway. On April 2, 2014, TY Lin completed a Structural Assessment Report (Attachment A) for the POC and Trail to provide a more detailed and enhanced accurate assessment than the LACDPW bi-annual reports. This report concluded that a portion of the POC should be replaced, and the structure is in need of seismic retrofitting and rehabilitation work to patch concrete. Additionally, recommendations were made to improve the bridge aesthetics. The report also provides suggestions for improvements to the Trail which has had numerous erosion and drainage problems. A complete replacement structure would be more cost effective than the partial replacement and repairs mentioned above. Discussion The POC crosses over the California Incline Bridge and Roadway between Ocean Avenue and Pacific Coast Highway (PCH). The Trail goes diagonally up the bluff to Palisades Park and exists near Idaho Avenue. The Trail and POC connect to another pedestrian overcrossing (owned by Caltrans) that goes over PCH providing pedestrian access to the beach from Palisades Park. Consultant Selection On March 30, 2015, the City published a Request for Proposals (RFP ) #SP2391 for engineering design services for the California Incline Pedestrian Overcrossing and Idaho Trail Project. The RFP was posted on the City’s online bidding site, and notices were advertised in the Santa Monica Daily Press on May 6, 2015 and May 13, 2015 in accordance with City Charter and Municipal Code provisions. A total of 1084 vendors were notified and 33 vendors downloaded the RFP. Three proposals were received on May 19, 2015 from Studio Pali Fekete Architects, TY Lin International, and Walter P Moore. A selection committee consisting of staff from the Civil Engineering Division reviewed, evaluated, and ranked the proposals. The selection process followed the consultant selection guidelines set forth by the Santa Monica Municipal Code. The selection 3 of 5 criteria included technical competence, past performance record, financial stability, quality of work, staffing capability to meet project timeliness, quality control, cost of services, and cost control and reporting. TY Lin ranked highest among the three firms and demonstrated that it has the most qualified team for the project. TY Lin demonstrated extensive knowledge and experience on numerous projects similar in nature. TY Lin’s bridge and pedestrian overcrossing experience was more extensive and specific to the City’s needs than the other two proposers. Relevant projects designed by TY Lin include the California Incline Pedestrian Overcrossing Structural Assessment Report, I -5 San Elijo Lagoon Bridge and Undercrossing Replacement, California Incline Bridge Replacement, Santa Monica Pier Bridge Replacement, Universal Pedestrian Bridge in Universal City, Rosemead Blvd. Safety Enhancements in Temple City, Las Flores Creek Pedestrian Bridge in Malibu, Long Beach Transit Gallery, and Mt. Vernon Ave. / UPRR Bridge Improvements in Colton, CA. In addition to their qualifications, the cost for services proposed by TY Lin is highly competitive, considering the cost proposals received from the three firms ranged from $375K to $450K. Staff recommends TY Lin as the best qualified firm to provide engineering design services for the California Incline Pedestrian Overcrossing and Idaho Trail project at a cost of $411,827 (including 10% contingency). Moving forward with an expedited design of the POC and Idaho Trail would allow staff to take advantage of the current closure of the California Incline Bridge and proceed through construction at a faster pace and lower costs. If the POC and Idaho Trail construction were to begin after the California Incline Bridge reopens, it would require closing the California Incline Bridge a second time which would result in a longer construction period and additional costs for encroachment permits and traffic control . Environmental Exemption The proposed California Incline Pedestrian Overcrossing and Idaho Trail Project is categorically exempt from CEQA pursuant to Sections 15302 and 15304 of the CEQA 4 of 5 Guidelines. Section 15302 provides exemption for a class of projects (Class 2) consisting of the replacement or reconstruction of existing structure and facilities where the new structure will be located on the same site as the structure replaced and will have substantially the same purpose and capacity. Section 15304 provides exemption for a class of projects (Class 4) consisting of minor alterations in the condition of land. The project will involve removing and rebuilding the pedestrian overcrossing that goes over the California Incline Bridge. The project also involves repairs and upgrading the Idaho Trail that goes diagonally up the bluff. Therefore, the project qualifies as a Class 2 and Class 4 exemption. In addition, none of the exceptions specified in Section 15300.2 of CEQA Guidelines apply that would preclude the use of these CEQA exemptions: the project site is not located in a sensitive environment; the project will not have a significant effect on the environment; the project would not damage scenic resources; the project would not be located on a hazardous waste site; and the project would not cause a cha nge to a historical resource. Therefore, this project is categorically exempt per Sections 15302 and 15304 of the CEQA Guidelines. 5 of 5 Financial Impacts and Budget Actions The agreement to be awarded to TY Lin is for an amount not to exceed $411,827. Funds are available in the FY 2015-16 Capital Improvement Program budget in account C010678.589000. Prepared By: Zach Pollard, Civil Engineer Approved Forwarded to Council Attachments: A. Structural Assessment Report California Incline Pedestrian Overcrossing (SP2059)STRUCTURALASSESSMENTREPORTApril 2, 2014 Page 1 of 24 Table of Contents Executive Summary ...................................................................................................................................... 3 1. Structure Description ............................................................................................................................ 5 2. Purpose and Need ................................................................................................................................. 6 3. Geotechnical Assessment ..................................................................................................................... 7 4. Structure Design Criteria ...................................................................................................................... 7 5. As-Built Structural Analysis ................................................................................................................. 8 6. Bridge Seismic Retrofit Strategy ........................................................................................................ 13 7. Bridge Rehabilitation .......................................................................................................................... 15 8. Drainage and Trail Analysis ............................................................................................................... 15 9. Aesthetic Evaluation and Opportunities ............................................................................................. 17 10. Full Structure Replacement ................................................................................................................ 18 11. Constructability ................................................................................................................................... 19 12. Cost Estimate ...................................................................................................................................... 19 13. Conclusions and Recommendations ................................................................................................... 20 Appendix A – Retrofit Plans and Trail Improvements ............................................................................... 21 Appendix B – Cost Estimates ..................................................................................................................... 22 Appendix C – Bridge Inspection Report ..................................................................................................... 23 Appendix D – Preliminary Geotechnical Report ........................................................................................ 24 Page 2 of 24 List of Figures and Tables Figure 1 - Bridge Plan View ........................................................................................................... 5 Figure 2 - Site Map ......................................................................................................................... 5 Figure 3 - Typical Section from As-Built Plans ............................................................................. 6 Figure 4 - Idaho Pedestrian Trail Looking South ........................................................................... 6 Figure 5 - Erosion at East Staircase ................................................................................................ 6 Figure 6 - Built-up Debris in V-Ditch ............................................................................................. 6 Figure 7 - Sandbags Lined Along East Staircase ............................................................................ 7 Figure 8 - Acceleration Response Spectrum ................................................................................... 7 Figure 9 - Extruded View of SAP2000 Model ............................................................................... 8 Figure 10 - Pile Head Deflection vs. Length ................................................................................ 10 Figure 11 - East Pier Wall ............................................................................................................. 10 Figure 12 - Hinge Detail at East Staircase from As-Built ............................................................ 12 Figure 13 - Model of West Pier Wall............................................................................................ 12 Figure 14 - Section of Steel Jacket Retrofit .................................................................................. 15 Figure 15 - Rebar Mesh and V-Ditch filled with Debris .............................................................. 15 Figure 16 - Drainage Pipe Adjoining V-Ditch .............................................................................. 16 Figure 17 - Chipped Paint on Exterior of Bridge and Existing Fence .......................................... 17 Figure 18 - Alternative Railing Concepts (a) Camino Del Norte Pedestrian Bridge, (b) Del Mar Heights Road Pedestrian Overcrossing ........................................................................ 18 Figure 19 - Existing Lighting Fixtures.......................................................................................... 18 Figure 20 - Neon Sign on West Staircase ..................................................................................... 18 Table 1 - Limit States and Load Factors for Load Rating .............................................................. 9 Table 2 - As-Built Demand and Capacity Results .......................................................................... 9 Table 3 - East Pier Wall Seismic Analysis Results....................................................................... 11 Table 4 - East Pier Wall Pile Seismic Analysis Results ............................................................... 11 Table 5 - West Pier Wall Seismic Analysis Results ..................................................................... 13 Table 6 - West Pier Wall Pile Seismic Analysis Results .............................................................. 13 Table 7 - Cost Estimates ............................................................................................................... 20 Page 3 of 24 Structural Assessment Report California Incline Pedestrian Overcrossing Executive Summary The California Incline Pedestrian Overcrossing (POC) provides a direct link for pedestrians between Palisades Park and Santa Monica Beach, via the Idaho Pedestrian Trail and Pacific Coast Highway POC. The California Incline POC is 56 years old and a portion of it is carved into eroding bluff slopes, which is compromising the stability of the structure and the trail. The City of Santa Monica has requested that a preliminary assessment be conducted to evaluate the structural integrity, drainage, and aesthetics of the POC and to provide recommendations for retrofit or replacement and for improving the drainage and maintenance of the Idaho trail. Structural analysis shows the bridge is need of seismic retrofitting and a portion of the structure should be replaced. The bridge needs rehabilitation work to patch concrete and recommendations are provided to improve the structure aesthetics. If all of the retrofitting, rehabilitation, and aesthetic improvements are implemented, it will be more cost effective to completely replace the structure. A replacement structure will have a longer service life and require less future maintenance than the rehabilitated structure. Based on the total cost of improvements, it is recommended the structure be replaced for an estimated construction cost of $720,000. Drainage and surface improvements of the Idaho Trail are estimated to cost $140,000, for a total project construction cost of $860,000. The total project cost including engineering design, environmental consulting, and construction management is estimated to be $1.5 million. Page 4 of 24 This page intentionally left blank. 1. Structure Description The California Incline Pedestrian Overcrossing (State Bridge No. 53C-1576, LA County Bridge No. 2635) spans over the California Incline roadway in the east-west direction providing pedestrian access from the Palisades Park (via Idaho Pedestrian Trail) CA Incline roadway and the Pacific Coast Highway POC. The structure was constructed in 1957 and consists of a cast-in-place reinforced concr U-shaped through-girder superstructure connected to staircase structures at the east and west ends. The main superstructure has a length of 56’-4” and is supported on a pier wall at the west staircase and cantilevers from a pier wall at the east end. The east staircase joins the Idaho Pedestrian Trail that is cut into the bluff above the Incline roadway. The east staircase is a continuation of the U-shaped girder superstructure and is supported by a on seat type hinges on the main superstructure slabs cantilevered from a pier wall that is Figure 2 - Site Map Page 5 of 24 The California Incline Pedestrian Overcrossing , LA County ) spans over the California west direction, pedestrian access from the Palisades Park (via Idaho Pedestrian Trail) down to the CA Incline roadway and the Pacific Coast The structure was constructed in 1957 and reinforced concrete superstructure that is connected to staircase structures at the east and west ends. The main superstructure has a and is supported on a pier wall at the west staircase and cantilevers from a pier staircase joins the Idaho Pedestrian Trail that is cut into the bluff above the CA east staircase is a shaped girder superstructure and is supported by a cast-in-drilled-hole (CIDH) pile footing at the north end on the main superstructure at the south end. The west staircase slabs cantilevered from a pier wall that is supported on a mat foundation with four The Idaho Pedestrian Trail is cut into the bluff slopes and connects the Palisades Park to the POC, has a length of approximately 398-feet and a vertical elevation change of about 4 trail is overlaid with asphalt concrete (AC) and has a drainage V east side and a chain link fence on the west. Figure 1 - Bridge Plan View Site Map hole (CIDH) pile footing at the north end and The west staircase consists of four CIDH piles. The Idaho Pedestrian Trail is cut into the nd connects the Palisades Park to the POC, has a length of and a vertical about 42-feet. The trail is overlaid with asphalt concrete (AC) and has a drainage V-ditch on the east side and a chain link fence on the Bridge Plan View Page 6 of 24 Figure 3 - Typical Section from As-Built Plans Figure 4 – Idaho Pedestrian Trail Looking South 2. Purpose and Need The bluff slopes are comprised of soils that are susceptible to wind and water erosion causing debris to build up in the trail V-ditch and clog the trail’s drainage pipe. At the connection of the east staircase and the trail, the erosion is significant and has exposed a portion of the staircase footing and washed out a section of the trail. To “bridge” the trail and staircase, wood planks have been placed and overlaid with AC. To provide additional support to the staircase, a steel H- pile has been placed under the eroded footing. Considering the age of the structure, a structural assessment of the bridge for service and earthquake loads was performed to determine its performance with current bridge codes. The minimum seismic requirement is for the structure to meet no- collapse criteria under the design level earthquake. The bridge inspection report dated March 19, 2010, located in Appendix C, lists the deck and superstructure in satisfactory condition and the substructure in good condition. The condition of the foundations and piles is unknown as they are Figure 5 - Erosion at East Staircase Figure 6 – Built-up Debris in V- Ditch Page 7 of 24 not accessible for inspection. The report recommends repairs to the bridge that include patching concrete spalls and delaminations in the deck. The inspection report also indicates the bridge as being closed due to the significant erosion at the east staircase; however it is currently open to the public. The aesthetics could use improvement as the bridge has various patches of paint, most likely to cover graffiti, dull railings, and old lighting. 3. Geotechnical Assessment A Preliminary Seismic Evaluation Report has been prepared by Earth Mechanics, Inc. (EMI). This report includes geotechnical, seismic, and foundation recommendations to aid in the analysis of the bridge. See Appendix D for the report. 4. Structure Design Criteria The following manuals and loading was used in evaluating the bridge: • AASHTO Manual for Bridge Evaluation, Second Edition, with 2011 Interim Revisions • AASHTO LRFD Bridge Design Specifications, Fourth Edition, 2007 with Caltrans Amendments, Version 4, November 2011 • AASHTO LRFD Guide Specifications for the Design of Pedestrian Bridges, Second Edition, December 2009 • Caltrans Memo to Designers • Caltrans Bridge Design Aids • Caltrans Seismic Design Criteria (SDC), Version 1.7, April 2013 Live Loading: 90 psf Pedestrian Live Load Figure 7 - Sandbags Lined Along East Staircase Figure 8 - Acceleration Response Spectrum Page 8 of 24 5. As-Built Structural Analysis The California Incline Pedestrian Overcrossing was analyzed for current pedestrian and seismic loading. It is assumed the bridge superstructure, piers, foundations, and piles are not deteriorated and the full strength of the members can be used in the analysis. As-built plans and survey data from the California Incline Bridge Replacement project were used to create a 3-dimensional model of the structure using the program SAP2000. The model included the superstructure, east staircase, pier walls and CIDH pile foundations. The weight of the west stairs and other nonstructural items are included in the model. Based on the as-built plans, the following nominal material properties were used in the analysis: • Concrete compressive strength, f’c = 3000 psi • Rebar yield strength, fy = 40,000 psi • Vertical pile rebar yield strength, fy = 50,000 psi Geotechnical data was used to model the effects of soil springs on the CIDH piles. The program LPILE was used to model individual piles to obtain forces and displacements. a) Pedestrian Loading Results Loading criteria from the AASHTO Manual for Bridge Evaluation was used to assess the sufficiency of the bridge to carry pedestrian loading. The criterion evaluates structural capacity of the superstructure at the service limit and strength limit states. The service limit state is the minimum strength needed to maintain the serviceability of a structure, i.e.: minimize concrete cracking to ensure durability of the concrete. The strength limit state has two loading levels: Inventory and Operating. The Inventory level represents the strength of the structure need to comply with the current bridge design code where the Operating level represents the minimum strength needed for typical loading. Table 1 summarizes the limit states and load factors for load rating: Figure 9 - Extruded View of SAP2000 Model Page 9 of 24 Table 1 - Limit States and Load Factors for Load Rating Bridge Type Limit State Dead Load γDC Dead Load γDW Live Load Service γLL Inventory γLL Operating γLL Reinforced Concrete Strength I 1.25 1.50 - 1.75 1.35 Service I 1.00 1.00 1.00 - - Table 2 summarizes the results of the analysis at critical locations on the bridge: Table 2 – As-Built Demand and Capacity Results Strength I Service I Inventory Design Load Operating Design Load Positive moment demand at east staircase OK OK OK Negative moment demand at face of East Pier wall NG OK OK Positive moment demand in segment spanning CA Incline OK OK OK Shear demand in Segment spanning CA Incline OK OK N/A OK – Indicates the structure has sufficient strength NG – Indicates the structure capacity is exceeded N/A – Not applicable at Service limit Based on the results of the analysis, the superstructure lacks sufficient strength to satisfy the Inventory load level at the east pier wall. However, it has sufficient strength at all other locations and satisfies the Operating load level and service limit state. Since the superstructure has adequate strength at the Operating load level of the strength limit state and meets the service limit state, strengthening for pedestrian loading is not needed. b) Seismic Analysis Results i. Pile Foundation at East Staircase The pile supporting the east staircase is marginally embedded into the bluff slope above the CA Incline roadway and has a shallow embedment of approximately 5 ft below the roadway. The portion of the bluff above the roadway does not provide lateral support for the pile and it behaves Page 10 of 24 as a column. Only the portion of the pile below the roadway was considered as providing lateral resistance. The seismic demands from the SAP2000 model were entered into the pile model in the program LPILE and the program could not converge to a solution due to instabilities. This is caused by the shallow embedment of the pile and the supporting soil being overstressed. Procedures in Caltrans Bridge Design Aids 12-44 were followed to estimate the minimum length of the pile needed to provide stability. This is accomplished in the LPILE program by increasing the length of the pile until there is no substantial change in the deflection of the pile. Caltrans recommends increasing this length 30% minimum as a factor of safety. Figure 10 shows a plot of the pile head deflection versus pile length. From this plot, the minimum length for stability should be 38-ft, and with a 30% factor of safety, this increases to 50-ft. This is 15-ft more than the current embedment length. Based on these results, the existing pile is not stable and retrofitting or replacement is needed. ii. East Pier Wall According to the as-built drawings, the wall longitudinal reinforcing is lap-spliced at the connection to the pile cap and has minimal transverse reinforcing comprised of #4 bars spaced at 12”. This detailing was common in bridges prior to 1971 and has performed poorly in past earthquakes resulting in shear failures and structural collapse. Although the lap splice is expected to develop the bar yield strength, the strength of the longitudinal reinforcement will degrade under cyclic loading and the moment capacity of the pier wall will reduce to a residual moment capacity. From the results shown in Table 3 the pier wall has sufficient displacement capacity which is greater than the demand displacement. However for the strong axis of the wall the Figure 11 - East Pier Wall Figure 10 - Pile Head Deflection vs. Length Page 11 of 24 displacement ductility demand should be less than 1.0 to comply with the current code. The strong axis shear demand exceeds the capacity indicating a shear failure in the wall is expected. Since shear failures are brittle they can lead to structural collapse and retrofitting of the wall is needed. Table 3 - East Pier Wall Seismic Analysis Results Displacement Shear Plastic Displacement Yield Displacement Displacement Capacity Displacement Demand Displacement Ductility Demand Displacement Ductility Capacity Shear Capacity Shear Demand Capacity > Demand ∆p ∆y ∆C ∆D µD < 1 (SA) µD < 4 (WA) µC > 3 φVn Vu (in) (in) (in) (in) (kip) (kip) Strong-Axis 2.37 0.94 3.31 2.4 2.6 10.0 57.7 125 NG Weak-Axis 13.97 5.10 19.07 0.63 0.1 10.6 10.23 10 OK SA – Strong Axis WA – Weak Axis Table 4 summarizes the results of the force demands in the east pier wall piles. The piles have sufficient axial tension and compression capacity. However the piles are 6% overloaded in shear strength combined with tension. From Caltrans Memo to Designers, damage to foundations is acceptable provided it does not lead to structural collapse. Based on the LPILE analysis, the piles remain stable under these forces and the slight overstrength in shear is considered acceptable, therefore no retrofitting of the east pier wall foundations is needed. Table 4 - East Pier Wall Pile Seismic Analysis Results Tension Pile Compression Pile (kip) (kip) Axial Demand -183 300 Capacity -290 530 Capacity > Demand OK OK Shear Demand 43 48.5 Capacity 40.7 121.3 Capacity > Demand NG OK Page 12 of 24 iii. East Staircase Hinge The girders of the east staircase are supported on a small seat hinge on the main superstructure girders that are approximately 8” long and 9” wide. Five ¾” diameter dowel bars cross the joint of the hinge keeping the two structures from separating. The dowel bars have sufficient strength for the seismic demands. However, Caltrans Seismic Design Criteria, for new structures, requires hinge seats to have a minimum length of 30 inches. Based on these criteria and the small size of the girder hinge seats could lead to collapse, retrofitting of the hinge seat is recommended. iv. West Pier Wall Results The west pier wall has an asymmetrical geometry and is supported on a mat foundation with four CIDH piles. Similar to the east pier wall, the west pier wall has minimal transverse reinforcement and the longitudinal bars are lap spliced at the top of the foundation. Figure 13 - Model of West Pier Wall From the results of the seismic analysis shown in Table 5 the west pier is much stiffer than the east pier wall, which results in small seismic displacement demands. The pier wall has adequate displacement and shear capacity. Based on these results, no retrofitting to the west pier wall is needed. Figure 12 - Hinge Detail at East Staircase from As-Built Page 13 of 24 Table 5 - West Pier Wall Seismic Analysis Results Displacement Shear Plastic Displacement Yield Displacement Displacement Capacity Displacement Demand Displacement Ductility Demand Displacement Ductility Capacity Shear Capacity** Shear Demand Capacity > Demand ∆p ∆y ∆C ∆D µD < 4* µC > 3 φVn Vu (in) (in) (in) (in) (kip) (kip) EAST-WEST 1.21 0.41 1.62 0.16 0.4 4.0 357 240 OK NORTH-SOUTH 1.21 0.19 1.40 0.62 3.3 7.4 357 138 OK * The pier wall is comprised of multiple walls and is considered to act as a column, therefore the target displacement ductility demand for a single column bent is used (SDC 2.2.4) ** Only concrete strength considered Table 6 shows the analysis results of the west pier wall piles. The piles have adequate axial and shear strength. Table 6 - West Pier Wall Pile Seismic Analysis Results Axial (kip) Shear (kip) Compression Demand Compression Capacity Capacity > Demand Tension Demand Tension Capacity Capacity > Demand Shear Demand Shear Capacity Capacity > Demand (kip) (kip) (kip) (kip) (kip) (kip) North Pile 43.5 530 OK 0 -290 OK 8.35 104.8 OK NW Pile 90.2 530 OK 0 -290 OK 14.29 105.8 OK SW Pile 101.1 530 OK 0 -290 OK 12.19 106.4 OK West Pile 133.9 530 OK 0 -290 OK 15.22 106.4 OK 6. Bridge Seismic Retrofit Strategy Results from the seismic analysis indicate the following bridge elements have deficiencies and require retrofitting: • Pile under the east staircase is unstable • East pier wall under main superstructure needs strengthening • Hinge seat at east staircase needs lengthening Page 14 of 24 Pile under East Staircase The location of the pile being in the bluff slope and under the east staircase structure makes retrofitting the pile difficult. However three alternatives were considered: installing an adjacent pile, constructing a tieback wall, and completely replacing the east staircase. A new pile installed next to the existing pile with sufficient embedment could provide the needed lateral stability. The only space for a new pile is on the west side of the existing pile. The new pile would need to overlap the existing pile a sufficient length, approximately 10 ft, to effectively transfer the loading. To construct the connection, the existing pile would be exposed from the bluff slope to facilitate the placement of additional reinforcing steel and concrete. This alternative has significant risks including: the possibility of destabilizing the existing pile during construction, increasing erosion, and initiating surficial bluff failures with removal soil around the pile. Given these risks this alternative is not recommended. Another option to stabilize the pile is to encapsulate it in a tieback anchor wall. This would entail installing prestressing anchors on either side of the pile and applying a concrete facing on the slope. After stressing the anchors, the tieback wall would effectively compress the pile against the slope. However there are some significant drawbacks. In theory this is structurally feasible but it is not known if a pile has been stabilized in this manner before. The bluff slopes are a significant visual resource and altering their form with a concrete facing would violate the Local Coastal Plan. The slope would continue to erode at the edges of the concrete facing potentially undermining the concrete. For these reasons this alternative is not recommended. The final alternative considered is to completely replace the east staircase with a new structure. Given the topography of the slope, the space available to construct new piles is west of the staircase. Therefore it is envisioned the replacement staircase would cantilever from columns to maintain the existing bridge alignment. A benefit of this alternative is the new staircase can be designed to not rely on the main superstructure for support, eliminating the need to retrofit the hinges. Replacement of the east staircase with a new independent structure is the recommended retrofit solution. A preliminary plan for the replacement of the staircase is in Appendix A. East Pier Wall Retrofit The shear strength of the east pier wall can be increased with a steel jacket casing. Seismically retrofitting columns with steel jackets is common practice and has been used on many bridges throughout California. The jacket encapsulates the wall and adds less than 12” in thickness to each side. Maintaining a wall profile is needed due to the limited space between the wall and the edge of the curb. On the long axis of the wall tight against the wall. A preliminary plan of the steel jacket retrofit is in Appendix A. Figure 7. Bridge Rehabilitation Based on field visits and information from the bridge inspection report, parts of the structure that are experiencing deterioration need repair. are recommended: • Removing and replacing spalled concrete • Epoxy injecting cracked concrete • Repairing deck delaminations These types of repairs are common and cost effective in extending the life of the structure. 8. Drainage and Trail Analysis Consideration of bridge drainage needs to include the Pedestrian Trail since it connects to the east staircase and concentrates runoff on the bluff. Run bluff slope and trail is carried down through a V east side of the trail. The V-ditch near the top of the east staircase that runs down to the CA Incline roadway. Check dams constructed of intermittently spaced along the V debris. Water that collects on the trail from the top of the east staircase travels down the staircase and across the bridge to the west staircase and then down to the sidew Page 15 of 24 On the long axis of the wall bolts are installed through the jacket to keep it all. A preliminary plan of the steel jacket retrofit is in Appendix A. Figure 14 – Section of Steel Jacket Retrofit Based on field visits and information from the bridge inspection report, parts of the structure that are experiencing deterioration need repair. The following rehabilitation measures Removing and replacing spalled concrete Epoxy injecting cracked concrete Repairing deck delaminations ommon and cost effective in extending the life of the structure. drainage needs to include the Idaho since it connects to the east staircase and on the bluff. Runoff that collects on the carried down through a V-ditch on the ditch connects to a drainage pipe staircase that runs down to the CA Incline roadway. Check dams constructed of steel rebar are intermittently spaced along the V-ditch in an attempt to collect . Water that collects on the trail from the top of the east staircase travels down the staircase and across the bridge to the west staircase and then down to the sidewalk next to the roadway. Figure 15 - Rebar Mesh and V Ditch filled with Debris bolts are installed through the jacket to keep it all. A preliminary plan of the steel jacket retrofit is in Appendix A. Based on field visits and information from the bridge inspection report, parts of the concrete ehabilitation measures ommon and cost effective in extending the life of the structure. Rebar Mesh and V- Ditch filled with Debris Page 16 of 24 According to the bridge as-built plans, a drainage grate and concrete inlet were constructed at the bottom of the trail adjacent to the landing of the east staircase, see Figure 1. A 10” corrugated metal pipe was connected to the inlet that transported water down to an inlet next to the roadway. Currently at this location, the slope is severely eroded from the trail down to the roadway indicating a past failure of the drainage system, see Figure 5. If the inlet grate exists, it is now covered with asphalt and wood planking and is not operational. The original corrugated metal pipe has been replaced with a flexible pipe. Debris and runoff from the bluffs above the trail fills the V- ditch and can clog the drainage pipe. The City has indicated that the trail is closed after large storm events to clean the debris. The clogging of the drainage pipe is likely the cause of the significant erosion at the east staircase. Improvements to the trail are recommended to provide better drainage and reduce the amount of eroded soil overflowing to the drains. These include replacement of the existing V-ditch with a standard curb and gutter, replacement of the trail pavement, construction of a chain link fence along the east side of the trail, and replacement of the existing drainage system. Replacing the V-ditch with curb and gutter will allow for easier debris removal through the use of a small bobcat. The addition of a chain link fence with a small mesh fabric will provide a barrier to keep most of the eroded material off of the trail. The existing drainage system should be replaced with a primary inlet, similar to the existing drainage pipe adjoining the V-ditch in Figure 16, and a secondary downstream overflow inlet. The secondary overflow inlet is proposed to have a steel grate cover and be located in a vertical sag in the trail prior to the stairs. The sag would be created by additional stairs and sloping the trail back to the north, creating a low point. A conceptual plan for the trail improvements is in Appendix A. The calculated runoff on the bridge is very small and there is no evidence of ponding water on the structure. Therefore, the drainage of the bridge is considered adequate and no modification is recommended. Figure 16 - Drainage Pipe Adjoining V-Ditch Page 17 of 24 9. Aesthetic Evaluation and Opportunities The California Incline POC is a reinforced concrete structure with sand colored masonry brick veneer on the pier walls. The bridge superstructure has a layer of cream-colored paint that is peeling. There are also patches of grey paint that was probably used to cover graffiti. The bridge has galvanized steel hand railings on the stairs and a curved galvanized steel chain link fence on the superstructure over the roadway. A unique aesthetic feature is the blue and white “Santa Monica” neon sign that is on the north side of the west staircase. Galvanized steel chain link fencing has been placed beneath the cantilevered slabs of the west staircase to discourage trespassers. Surface mounted lights are placed on the interior of the south walls of the bridge. Below is a list of measures that can be taken to improve the bridge aesthetics: • Pressure washing the exterior of the bridge concrete and brick veneer and repainting the superstructure concrete • Replace the chain link fence on the main superstructure with a painted fence that is more open and colorful (See Figure 19) • Replace handrails on the staircases with stainless steel or aluminum rails • Replace the wall mounted bridge light fixtures with decorative fixtures and use LED lighting • Rehabilitate the existing neon sign or relocate on a replacement structure Figure 17 - Chipped Paint on Exterior of Bridge and Existing Fence Page 18 of 24 (a) (b) Figure 18 - Alternative Railing Concepts (a) Camino Del Norte Pedestrian Bridge, (b) Del Mar Heights Road Pedestrian Overcrossing Figure 19 - Existing Lighting Fixtures Figure 20 - Neon Sign on West Staircase 10. Full Structure Replacement A possible alternative to retrofitting and rehabilitating the existing bridge is to completely replace the existing structure. This alternative would have the benefit of a new structure that was designed to the latest bridge design code that had a minimum service life of 75 years. Full structure replacement would provide opportunities for changing the geometry of the bridge and possibly eliminating the staircases. A cost estimate to replace the bridge in-kind is included in this report. Page 19 of 24 11. Constructability Removal and replacement the east staircase will have construction challenges given its location on the bluff slope. Eroded soil from the bluff has built up and is being retained by the east staircase as shown in Figure 7. Sandbags have been placed in an attempt to prevent the soil from spilling on the stairs. After the east staircase is removed, the loose eroded soils require removal from the slope to allow construction of the new staircase. The replacement staircase can be precast or cast-in-place, however both methods of construction have challenges. A precast structure has little tolerance for misalignment and will need unique, nonstandard, connections with the columns and foundations. Cast-in-place construction will be difficult with little room to work and questionable strength of the bluff slope to support falsework and concrete as it cures. Construction of the east pier wall retrofit is straightforward with removal of the brick veneer, coring of holes, and installation of the steel jacket. Construction of the replacement of the east staircase and retrofit of the pier wall will impact pedestrians on the bridge, trail, and traffic on CA Incline. Removal and replacement of the east staircase could take several months with no pedestrian access to the POC or Idaho Trail. Space to install new foundations and installation of the pier wall retrofit would also require disruption to traffic on the roadway. The bridge rehabilitation and aesthetic improvements can be made with minor disruptions to pedestrians and traffic. Full bridge removal and replacement would require complete closure of the trail and roadway. The roadway would open to traffic after the existing structure was removed, new foundations were installed, and falsework was erected for the new structure. Access for pedestrians would not be provided until the new structure was complete. Completion of the project is expected to take several months but be less than a year. 12. Cost Estimate Preliminary structure quantities of the proposed improvements were estimated using the guidelines in Caltrans Bridge Design Aids for general plan quantity takeoffs. Unit prices were taken from Caltrans Cost Statistics that are averaged over the years 2008 through 2013, and were adjusted to the current cost index. The unit prices were further adjusted based on specific site conditions and relative economy of scale. A cost estimate to replace the bridge in-kind is provided for comparison. Other replacement structure options are possible but are beyond the scope of this report. Page 20 of 24 Table 7 lists cost estimates for the various structure improvements. Table 7 – Cost Estimates Item Cost Estimate East Pier Wall Retrofit $160,000 East Staircase Replacement $350,000 Bridge Rehabilitation $40,000 Bridge Aesthetic Improvements $150,000 In-Kind Bridge Replacement $720,000 Trail Improvements $140,000 13. Conclusions and Recommendations The California Incline POC requires seismic retrofitting and rehabilitation work is also recommended to extend its service life. As an option the bridge aesthetics could also be improved. The estimated total cost of these improvements is $700,000. The estimated cost to replace the bridge in-kind is $720,000. Since the cost of the improvements is nearly the same as a new structure, complete structure replacement is recommended. Removal of soil from the Idaho Trail will be an on-going maintenance requirement due to the erosion of the bluff slopes. However some improvements can be made to improve the drainage and minimize the trail maintenance. The recommended trail improvements are estimated to cost $140,000. The total construction cost of both the bridge and trail improvements is estimated to be $860,000. The total project cost including engineering design, environmental consulting, and construction management is estimated to be $1.5 million. Advanced planning level cost estimates for engineering, consulting, and construction are in Appendix B. . Page 21 of 24 Appendix A – Retrofit Plans and Trail Improvements Page 22 of 24 Appendix B – Cost Estimates February 2, 2014 California Incline Pedestrian Overcrossing Replacement - Total Project Cost Estimate Consulting Fees Bridge/Stair Design 160,000.00$ Civil Design 80,000.00$ Environmental Consulting 125,000.00$ Geotechnical Engineering 20,000.00$ Survey 10,000.00$ Project Management (10%)38,500.00$ Total 433,500.00$ Construction Costs Bridge Replacement 720,000.00$ (includes 25% contingency) Trail Improvements 140,000.00$ (includes 25% contingency) Traffic Control 50,000.00$ SWPPP 26,000.00$ Construction Management (15%)140,400.00$ Total 1,076,400.00$ Total Project Cost 1,509,900.00$ Rounded Cost for Budgeting 1,510,000.00$ Assumptions: - Project is funded by City of Santa Monica. - Environmental document only needs to comply with CEQA and is an IS/MND. - Traffic control will not require re-striping or signal modifications. - Caltrans encroachment permit will be needed for flagging and lane closures on PCH. - A permit with the California Coastal Commission will be needed and will be obtained by the City. - Temporary closures on CA Incline will be needed for bridge removal, falsework erection, foundation construction, concrete pouring, and falsework removal. Reduced lane widths on CA Incline will be needed during construction. - Closure of sidewalk on CA Incline and PCH POC will be needed during construction. - Bridge will be replaced in-kind, in existing bridge footprint with stairs and modified connection to trail. - Bridge aesthetics will be simple with colored/textured concrete, decorative rail, and recessed lighting. - No utility relocations will be needed. - Additional survey points may be needed to tie to existing improvements. - Cost estimate is for work in 2014. - ADA compliance for bridge is not required since improvements are matching existing trail which is not ADA compliant. GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE Revised December 3 2007Revised - December 3, 2007 RCVD BY JTY IN ESTRCVD BY:JTY IN EST: OUT EST:OU S BRIDGE C lif i I li P d t i O i BR N 53C 1576 DISTRICT LABRIDGE:California Incline Pedestrian Overcrossing BR. No.:53C-1576 DISTRICT:LA TYPE:East Staircase Replacement RTE:p CU:CO:CU:CO: EA PMEA:PM: LENGTH:WIDTH:AREA (SF)=() DESIGN SECTION:DESIGN SECTION: # OF STRUCTURES IN PROJECT EST NO# OF STRUCTURES IN PROJECT :EST. NO. PRICES BY :SPIRAS COST INDEX: PRICES CHECKED BY :PSMITH DATE:10/8/2013PRICES CHECKED BY :PSMITH DATE:10/8/2013 QUANTITIES BY SPIRAS DATE 10/8/2013QUANTITIES BY:SPIRAS DATE:10/8/2013 CODE CONTRACT ITEMS TYPE UNIT QUANTITY PRICE AMOUNTQ 192003 STRUCTURE EXCAVATION (BRIDGE)CY 60 $300 00 $18 000 00192003STRUCTURE EXCAVATION (BRIDGE)CY 60 $300.00 $18,000.00 193003 STRUCTURE BACKFILL (BRIDGE)CY 30 $250 00 $7 500 00193003STRUCTURE BACKFILL (BRIDGE)CY 30 $250.00 $7,500.00 490605 36" CAST-IN-DRILLED-HOLE CONCRETE PILING LF 100 $450.00 $45,000.00$$, 510051 STRUCTURAL CONCRETE BRIDGE FOOTING CY 25 $500 00 $12 500 00510051STRUCTURAL CONCRETE, BRIDGE FOOTING CY 25 $500.00 $12,500.00 510053 STRUCTURAL CONCRETE BRIDGE CY 30 $3 500 00 $105 000 00510053STRUCTURAL CONCRETE, BRIDGE CY 30 $3,500.00 $105,000.00 520102 BAR REINFORCING STEEL (BRIDGE)LB 11,300 $2.75 $31,075.00(),$$, BRIDGE REMOVAL (PORTION)CY 10 $1 000 00 $10 000 00BRIDGE REMOVAL (PORTION)CY 10 $1,000.00 $10,000.00 SUBTOTAL $229 075SUBTOTAL$229,075 TIME RELATED OVERHEAD $22,908, ROUTING MOBILIZATION ( @ 10 % )$27 998ROUTINGMOBILIZATION ( @ 10 % )$27,998 SUBTOTAL BRIDGE ITEMS $279 9811. DES SECTION SUBTOTAL BRIDGE ITEMS $279,981 2. OFFICE OF BRIDGE DESIGN - NORTH CONTINGENCIES (@ 25%) $69,995(@ ), 3 OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $349 9763. OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $349,976 COST PER SQ FOOT4. OFFICE OF BRIDGE DESIGN - SOUTH COST PER SQ. FOOT 5. OFFICE OF BRIDGE DESIGN - WEST BRIDGE REMOVAL (CONTINGENCIES INCL.)() 6 OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES6. OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES GRAND TOTAL $349 976 GRAND TOTAL $349,976 COMMENTS: BUDGET ESTIMATE AS OF $350,000, E l t d B d t E ti t t Mid i t f C t ti *Escalated Budget Estimate to Midpoint of Construction *gp Escalation Rate per Year 50%Escalation Rate per Year 5.0% Years Beyond Escalated Years Beyond EscalatedYears Beyond Escalated Years Beyond Escalated Mid i t Bd tEt Mid i t Bd tEt * Escalated budget estimate is provided for information only actual Midpoint Budget Est.Midpoint Budget Est. Escalated budget estimate is provided for information only, actual construction costs may vary Escalated budget estimates provided do not 1 $368,000 4 $425,000construction costs may vary. Escalated budget estimates provided do not l D t tllit dt ttit ll ,, 2 $386 000 5 $446 000 replace Departmental policy to update cost estimates annually.2 $386,000 5 $446,000 3 $405 0003$405,000 GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE Revised December 3 2007Revised - December 3, 2007 RCVD BY JTY IN ESTRCVD BY:JTY IN EST: OUT EST:OU S BRIDGE C lif i I li P d t i O i BR N 53C 1576 DISTRICT LABRIDGE:California Incline Pedestrian Overcrossing BR. No.:53C-1576 DISTRICT:LA TYPE:East Pier Wall Steel Jacket Retrofit RTE: CU:CO:CU:CO: EA PMEA:PM: LENGTH:WIDTH:AREA (SF)=() DESIGN SECTION:DESIGN SECTION: # OF STRUCTURES IN PROJECT EST NO# OF STRUCTURES IN PROJECT :EST. NO. PRICES BY :SPIRAS COST INDEX: PRICES CHECKED BY :PSMITH DATE:10/8/2013PRICES CHECKED BY :PSMITH DATE:10/8/2013 QUANTITIES BY SPIRAS DATE 10/8/2013QUANTITIES BY:SPIRAS DATE:10/8/2013 CONTRACT ITEMS TYPE UNIT QUANTITY PRICE AMOUNTQ 515161 CORE CONCRETE (1 3/4")LF 60 $80 00 $4 800 00515161CORE CONCRETE (1 3/4 )LF 60 $80.00 $4,800.00 550110 COLUMN CASING LB 4 400 $20 00 $88 000 00550110COLUMN CASING LB 4,400 $20.00 $88,000.00 750500 MISCELLANEOUS METAL LB 330 $37.00 $12,210.00$$, SUBTOTAL $105 010SUBTOTAL$105,010 TIME RELATED OVERHEAD $10,501, ROUTING MOBILIZATION ( @ 10 % )$12 835ROUTINGMOBILIZATION ( @ 10 % )$12,835 SUBTOTAL BRIDGE ITEMS $128 3461. DES SECTION SUBTOTAL BRIDGE ITEMS $128,346 2. OFFICE OF BRIDGE DESIGN - NORTH CONTINGENCIES (@ 25%) $32,086(@ ), 3 OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $160 4323. OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $160,432 COST PER SQ FOOT4. OFFICE OF BRIDGE DESIGN - SOUTH COST PER SQ. FOOT 5. OFFICE OF BRIDGE DESIGN - WEST BRIDGE REMOVAL (CONTINGENCIES INCL.)() 6 OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES6. OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES GRAND TOTAL $160 432 GRAND TOTAL $160,432 COMMENTS: BUDGET ESTIMATE AS OF $160,000, E l t d B d t E ti t t Mid i t f C t ti *Escalated Budget Estimate to Midpoint of Construction *gp Escalation Rate per Year 50%Escalation Rate per Year 5.0% Years Beyond Escalated Years Beyond EscalatedYears Beyond Escalated Years Beyond Escalated Mid i t Bd tEt Mid i t Bd tEt * Escalated budget estimate is provided for information only actual Midpoint Budget Est.Midpoint Budget Est. Escalated budget estimate is provided for information only, actual construction costs may vary Escalated budget estimates provided do not 1 $168,000 4 $194,000construction costs may vary. Escalated budget estimates provided do not l D t tllit dt ttit ll ,, 2 $176 000 5 $204 000 replace Departmental policy to update cost estimates annually.2 $176,000 5 $204,000 3 $185 0003$185,000 GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE Revised December 3 2007Revised - December 3, 2007 RCVD BY JTY IN ESTRCVD BY:JTY IN EST: OUT EST:OU S BRIDGE C lif i I li P d t i O i BR N 53C 1576 DISTRICT LABRIDGE:California Incline Pedestrian Overcrossing BR. No.:53C-1576 DISTRICT:LA TYPE:Bridge Rehabilitation RTE:g CU:CO:CU:CO: EA PMEA:PM: LENGTH:WIDTH:AREA (SF)=() DESIGN SECTION:DESIGN SECTION: # OF STRUCTURES IN PROJECT EST NO# OF STRUCTURES IN PROJECT :EST. NO. PRICES BY :SPIRAS COST INDEX: PRICES CHECKED BY :PSMITH DATE:10/8/2013PRICES CHECKED BY :PSMITH DATE:10/8/2013 QUANTITIES BY SPIRAS DATE 10/8/2013QUANTITIES BY:SPIRAS DATE:10/8/2013 CONTRACT ITEMS TYPE UNIT QUANTITY PRICE AMOUNTQ BRIDGE REHABILITATION SQFT 175 $150 00 $26 250 00BRIDGE REHABILITATION SQFT 175 $150.00 $26,250.00 (Q tit 5% f th f i h bilit t d)(Quantity assumes 5% of the surface is rehabilitated) SUBTOTAL $26 250SUBTOTAL$26,250 TIME RELATED OVERHEAD $2,625, ROUTING MOBILIZATION ( @ 10 % )$3 208ROUTINGMOBILIZATION ( @ 10 % )$3,208 SUBTOTAL BRIDGE ITEMS $32 0831. DES SECTION SUBTOTAL BRIDGE ITEMS $32,083 2. OFFICE OF BRIDGE DESIGN - NORTH CONTINGENCIES (@ 25%) $8,021(@ ), 3 OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $40 1043. OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $40,104 COST PER SQ FOOT4. OFFICE OF BRIDGE DESIGN - SOUTH COST PER SQ. FOOT 5. OFFICE OF BRIDGE DESIGN - WEST BRIDGE REMOVAL (CONTINGENCIES INCL.)() 6 OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES6. OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES GRAND TOTAL $40 104 GRAND TOTAL $40,104 COMMENTS: BUDGET ESTIMATE AS OF $40,000, E l t d B d t E ti t t Mid i t f C t ti *Escalated Budget Estimate to Midpoint of Construction *gp Escalation Rate per Year 50%Escalation Rate per Year 5.0% Years Beyond Escalated Years Beyond EscalatedYears Beyond Escalated Years Beyond Escalated Mid i t Bd tEt Mid i t Bd tEt * Escalated budget estimate is provided for information only actual Midpoint Budget Est.Midpoint Budget Est. Escalated budget estimate is provided for information only, actual construction costs may vary Escalated budget estimates provided do not 1 $42,000 4 $48,000construction costs may vary. Escalated budget estimates provided do not l D t tllit dt ttit ll ,, 2 $44 000 5 $50 000 replace Departmental policy to update cost estimates annually.2 $44,000 5 $50,000 3 $46 0003$46,000 GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE Revised December 3 2007Revised - December 3, 2007 RCVD BY JTY IN ESTRCVD BY:JTY IN EST: OUT EST:OU S BRIDGE C lif i I li P d t i O i BR N 53C 1576 DISTRICT LABRIDGE:California Incline Pedestrian Overcrossing BR. No.:53C-1576 DISTRICT:LA TYPE:Aesthetic Improvements RTE:p CU:CO:CU:CO: EA PMEA:PM: LENGTH:WIDTH:AREA (SF)=() DESIGN SECTION:DESIGN SECTION: # OF STRUCTURES IN PROJECT EST NO# OF STRUCTURES IN PROJECT :EST. NO. PRICES BY :SPIRAS COST INDEX: PRICES CHECKED BY :PSMITH DATE:10/8/2013PRICES CHECKED BY :PSMITH DATE:10/8/2013 QUANTITIES BY SPIRAS DATE 10/8/2013QUANTITIES BY:SPIRAS DATE:10/8/2013 CONTRACT ITEMS TYPE UNIT QUANTITY PRICE AMOUNTQ 017456 REMOVE HANDRAIL LF 265 $10 00 $2 650 00017456REMOVE HANDRAIL LF 265 $10.00 $2,650.00 153235 CLEAN BRIDGE DECK SQFT 3 500 $3 25 $11 375 00153235CLEAN BRIDGE DECK SQFT 3,500 $3.25 $11,375.00 590280 PAINT CONCRETE SURFACING SQFT 3,000 $5.00 $15,000.00Q,$$, 833024 CHAIN LINK RAILING (TYPE 4)LF 113 $200 00 $22 533 33833024CHAIN LINK RAILING (TYPE 4)LF 113 $200.00 $22,533.33 833088 TUBULAR HANDRAILING LF 265 $105 00 $27 825 00833088TUBULAR HANDRAILING LF 265 $105.00 $27,825.00 BRIDGE LIGHTING EA 19 $1,000.00 $19,000.00$,$, SUBTOTAL $98 383SUBTOTAL$98,383 TIME RELATED OVERHEAD $9,838, ROUTING MOBILIZATION ( @ 10 % )$12 025ROUTINGMOBILIZATION ( @ 10 % )$12,025 SUBTOTAL BRIDGE ITEMS $120 2461. DES SECTION SUBTOTAL BRIDGE ITEMS $120,246 2. OFFICE OF BRIDGE DESIGN - NORTH CONTINGENCIES (@ 25%) $30,062(@ ), 3 OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $150 3083. OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $150,308 COST PER SQ FOOT4. OFFICE OF BRIDGE DESIGN - SOUTH COST PER SQ. FOOT 5. OFFICE OF BRIDGE DESIGN - WEST BRIDGE REMOVAL (CONTINGENCIES INCL.)() 6 OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES6. OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES GRAND TOTAL $150 308 GRAND TOTAL $150,308 COMMENTS: BUDGET ESTIMATE AS OF $150,000, E l t d B d t E ti t t Mid i t f C t ti *Escalated Budget Estimate to Midpoint of Construction *gp Escalation Rate per Year 50%Escalation Rate per Year 5.0% Years Beyond Escalated Years Beyond EscalatedYears Beyond Escalated Years Beyond Escalated Mid i t Bd tEt Mid i t Bd tEt * Escalated budget estimate is provided for information only actual Midpoint Budget Est.Midpoint Budget Est. Escalated budget estimate is provided for information only, actual construction costs may vary Escalated budget estimates provided do not 1 $158,000 4 $183,000construction costs may vary. Escalated budget estimates provided do not l D t tllit dt ttit ll ,, 2 $166 000 5 $192 000 replace Departmental policy to update cost estimates annually.2 $166,000 5 $192,000 3 $174 0003$174,000 GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE GENERAL PLAN ESTIMATE X ADVANCE PLANNING ESTIMATE Revised December 3 2007Revised - December 3, 2007 RCVD BY JTY IN ESTRCVD BY:JTY IN EST: OUT EST:OU S BRIDGE C lif i I li P d t i O i BR N 53C 1576 DISTRICT LABRIDGE:California Incline Pedestrian Overcrossing BR. No.:53C-1576 DISTRICT:LA TYPE:Full Structure Replacement In-Kind RTE:p CU:CO:CU:CO: EA PMEA:PM: LENGTH:WIDTH:AREA (SF)=() DESIGN SECTION:DESIGN SECTION: # OF STRUCTURES IN PROJECT EST NO# OF STRUCTURES IN PROJECT :EST. NO. PRICES BY :SPIRAS COST INDEX: PRICES CHECKED BY :PSMITH DATE:10/8/2013PRICES CHECKED BY :PSMITH DATE:10/8/2013 QUANTITIES BY SPIRAS DATE 10/8/2013QUANTITIES BY:SPIRAS DATE:10/8/2013 CONTRACT ITEMS TYPE UNIT QUANTITY PRICE AMOUNTQ BRIDGE REPLACEMENT SQFT 850 $500 00 $425 000 00BRIDGE REPLACEMENT SQFT 850 $500.00 $425,000.00 BRIDGE REMOVAL CY 102 $450 00 $45 900 00BRIDGE REMOVAL CY 102 $450.00 $45,900.00 SUBTOTAL $470 900SUBTOTAL$470,900 TIME RELATED OVERHEAD $47,090, ROUTING MOBILIZATION ( @ 10 % )$57 554ROUTINGMOBILIZATION ( @ 10 % )$57,554 SUBTOTAL BRIDGE ITEMS $575 5441. DES SECTION SUBTOTAL BRIDGE ITEMS $575,544 2. OFFICE OF BRIDGE DESIGN - NORTH CONTINGENCIES (@ 25%) $143,886(@ ), 3 OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $719 4313. OFFICE OF BRIDGE DESIGN - CENTRAL BRIDGE TOTAL COST $719,431 COST PER SQ FOOT4. OFFICE OF BRIDGE DESIGN - SOUTH COST PER SQ. FOOT 5. OFFICE OF BRIDGE DESIGN - WEST BRIDGE REMOVAL (CONTINGENCIES INCL.)() 6 OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES6. OFFICE OF BRIDGE DESIGN SOUTHERN CALIFORNIA WORK BY RAILROAD OR UTILITY FORCES GRAND TOTAL $719 431 GRAND TOTAL $719,431 COMMENTS: BUDGET ESTIMATE AS OF $720,000, E l t d B d t E ti t t Mid i t f C t ti *Escalated Budget Estimate to Midpoint of Construction *gp Escalation Rate per Year 50%Escalation Rate per Year 5.0% Years Beyond Escalated Years Beyond EscalatedYears Beyond Escalated Years Beyond Escalated Mid i t Bd tEt Mid i t Bd tEt * Escalated budget estimate is provided for information only actual Midpoint Budget Est.Midpoint Budget Est. Escalated budget estimate is provided for information only, actual construction costs may vary Escalated budget estimates provided do not 1 $756,000 4 $876,000construction costs may vary. Escalated budget estimates provided do not l D t tllit dt ttit ll ,, 2 $794 000 5 $920 000 replace Departmental policy to update cost estimates annually.2 $794,000 5 $920,000 3 $834 0003$834,000 Page 23 of 24 Appendix C – Bridge Inspection Report Page 24 of 24 Appendix D – Preliminary Geotechnical Report 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 Earth Mechanics, Inc. Geotechnical & Earthquake Engineering TECHNICAL MEMORANDUM DATE: October 10, 2013 EMI PROJECT NO: 13-138 PREPARED FOR: Peter Smith / TY Lin International (TY Lin) PREPARED BY: Eric Brown / Earth Mechanics, Inc. (EMI) SUBJECT: Preliminary Seismic Evaluation Report California Incline Pedestrian Overcrossing City of Santa Monica, California 1.0 Introduction This memorandum has been prepared to provide the necessary geotechnical information to assist the structural designers in the seismic evaluation for the California Incline Pedestrian Overcrossing (POC) in the city of Santa Monica. This report generally follows the requirements for a Preliminary Foundation Report (PFR) in accordance with the California Department of Transportation (Caltrans) guidelines for Foundation Report Preparation for Bridges (Caltrans, 2009). This Technical Memorandum includes preliminary geotechnical, seismic, and foundation recommendations for the seismic evaluation of the subject structure. The recommendations contained in this memorandum should be considered as preliminary; final design recommendations for seismic retrofit will be developed after approval of the retrofit strategy. 2.0 Project Location The project site is located in Los Angeles County California, in the City of Santa Monica. The California Incline (Incline) is a combination cut roadway and sidehill viaduct that scales the Pacific Palisades bluff from Pacific Coast Highway (PCH) to Ocean Avenue approximately 0.75 miles north of the intersection of Interstate 10 and PCH. The California Incline POC is one of two overcrossings that that carry pedestrians over the California Incline and PCH between Palisades Park and Santa Monica State Beach. The project site is shown in Figure 1. 3.0 Site Geology The project area is along the coastal bluffs in Santa Monica along the coastal margin of the Los Angles Basin and along the southern edge of the Santa Monica Mountains. The area straddles the boundary between the Peninsular Ranges and the Western Transverse Ranges geologic/physiographic provinces. Part of the city is on the southern slope of the mountains, part is within the canyons that head into the Santa Monica Mountains, and the rest is on the Santa Monica Plain. The Santa Monica Plain is an alluvial fan terrace emanating from the Santa Monica Mountains. This alluvial surface slopes gently southerly and extends to the southern city California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 2 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 boundary which is along the north margin of an east-west trending ancient river valley now occupied by Ballona Creek. The Santa Monica Plain is underlain by alluvial deposits eroded from the Santa Monica Mountains on the north. These are underlain at depth by Pleistocene marine deposits of the Lakewood Formation, which in turn overlie the Pliocene-age Pico-Repetto Formation (Fernando). These overlie predominantly Tertiary-age Marine deposits (Modelo, Monterey) that overlie basement rocks of the Jurassic-age Santa Monica Slate. The basement rocks are about 5,000 to 6,000 feet below the Santa Monica Plain. The slate and the overlying Tertiary-age rocks, as well as Cretaceous-age rocks, are exposed in the Santa Monica Mountains to the north. The large difference in depth of these formations from north to south is due to folding and faulting along the mountain front which have uplifted the formations on the north. The geologic formation making up the bluffs at the Santa Monica Incline is predominantly Pleistocene-age fan alluvium consisting of lenticular beds of gravel, sand, silt, and clay. The alluvial layers are horizontally bedded. The Pleistocene alluvium overlies Pleistocene marine deposits at depth. The underlying marine deposits consist of stiff hard blue-gray clay and fine sand. 4.0 Subsurface Conditions Between December 8 and December 11, 1997, EMI performed a field investigation for the proposed replacement of the California Incline Viaduct, where ten hollow-stem auger borings were performed along the existing Incline roadway. The borings varied in depth between 50 and 100 feet below grade with the deepest boring penetrating to about elevation -32 ft. Log-of-Test- Boring (LOTB) sheets from that investigation are included in Attachment 1. URS conducted twelve soil borings along the top of the bluffs in the Palisades Park in June 2002 (URS, 2006). Of those twelve borings, two 6-inch diameter hollow-stem auger vertical borings (B-7 and B-8) were performed near the subject project and were advanced to depths of 131 and 100 ft with a bottom of boring elevation of -13 and +5 ft, respectively. The borings are referred to as URS B-7 and URS B-8 in this report. In April 2009, URS conducted two 28-inch diameter bucket-auger borings (URS BA-1 and URS BA-2). Those borings were also drilled along the top of the bluffs in the Palisades Park down to depths of about 101 and 110 ft with a bottom of boring elevation of about +10 and +6 feet, resectively. Based on the soils information obtained during the investigation, the site is underlain by alluvial deposits consisting of silt, clay, sand and abundant gravel. Between road grade and about 20 to 25 feet below grade, the foundation soils are predominately moist, stiff to very stiff silt and clay with occasional sand and gravel. This material is underlain by a 20 to 25 feet thick layer of moist, very dense sandy silt and silty sand with abundant clay and gravel. About 40 to 50 feet below road grade, the material generally consists of wet, very dense clayey sand, sand with silt, silty sand and silty gravel. Groundwater. Groundwater was encountered in seven EMI borings between El. +1 feet and +7 ft. Ground water is at a depth of about 10 ft below PCH (approximately El. +7 to +8 ft) along the California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 3 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 base of the bluffs (California Geological Survey, 1997). Bucket auger borings drilled by URS (2009) along the top of the bluff encountered groundwater at an El. +9 ft. Boreholes drilled by URS (2006) documented the distribution of the ground water and found ground-water depths ranging from 4 to 100 feet above mean sea level. Historic records suggest that the higher ground- water levels probably are a result of perched conditions. URS installed 16 hydraugers along the lower portions of the bluffs but encountered ground water in only three of them (URS, 2006). This indicates that ground water is distributed in widely scattered zones. However, after long periods of rainfall, local water seeps can be observed in the bluff along with large areas of saturated soils on the bluff face. 5.0 Seismic Evaluation The site is located in a seismically active region and is subject to shaking from both local and distant earthquakes. Table 1 lists the nearest active faults, fault type and their maximum earthquake magnitude according to the Caltrans Fault Database (Shantz and Merriam, 2012). The site to fault distances were determined using the Caltrans ARS Online web tool (Caltrans, 2012). Large events on the Santa Monica and Anacapa-Dume fault control seismic design of the project. Table 1. Fault Data Fault Fault Type (1) Maximum Earthquake Magnitude Distance from Site to Fault (miles) Surface Fault/Blind Fault Anacapa-Dume alt 1 Rev 7.2 0.4 Surface Santa Monica fault SS 7.0 0.7 Surface Malibu Coast alt 2 SS 6.6 0.7 Surface Newport Inglewood fault zone (N. Los Angeles Basin section) SS 7.2 6.3 Surface Note: (1). Rev = Reverse, SS = Strike Slip Fault Rupture. The Santa Monica fault appears to comprise two discrete segments, a northern segment and a southern segment; the northern segment is a continuation of the Potrero Canyon fault and extends east-northeasterly just south of Brentwood Knoll into West Los Angeles; the southern branch extends easterly from the mouth of Santa Monica Canyon, forming a ground- water barrier a short distance (blocks) north of the Santa Monica Freeway (I-10) nearly as far east as the 405 Freeway in West Los Angeles. A third location between the north and south branches has been proposed by Dolan and Sieh (1991) based on geomorphic data in the form of a series of left-stepping en echelon features, but with the same trend as the north and south branches. Surficial evidence to the east, of all of these trends, has been removed by erosion so the connection with folds and faults to the east is obscured. None of these traces are near the Incline so the potential for surface fault rupture beneath the California Incline POC is considered low. California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 4 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 ARS Curve Recommendations. The design ARS curve for the California Incline POC was developed in accordance with the 2012 SDC (Caltrans, 2012a) procedures, considering the following response spectra: • Deterministic Criteria based on late-Quaternary faults in the Caltrans fault database (Shantz and Merriam, 2012); • Probabilistic Criteria based on 5% in 50 years probability of exceedance ground motion; and • Minimum Deterministic Spectrum based on a Mw = 6.5 strike-slip event occurring at a distance of 7.5 miles (12 km) from the site. The design ARS curve is the envelope of the above spectra. The Caltrans ARS Online (V2.2.06) web tool was used to develop the deterministic and probabilistic ARS curves. The Caltrans ARS Online (V2.2.06) web tool develops the deterministic spectrum using the average of median response spectra calculated by two Next Generations Attenuations (NGA) ground motion prediction equations developed by Campbell- Bozorgnia (2008) and Chiou-Youngs (2008). These equations are applied to all faults considered to be active in the last 750,000 years (late-Quaternary age) that are capable of producing a moment magnitude earthquake of 6.0 or greater. The Caltrans ARS (V2.2.06) Online tool obtains the probabilistic spectrum from the USGS (2008) National Hazard Map for 5% probability of exceedance in 50 years. The parameters of small-strain shear wave velocity for the upper 100 ft (Vs30) of subsurface materials is correlated based on the available borings, and both the deterministic and probabilistic spectra account for soil effects through incorporation of the parameter Vs30. The following table summarizes the pertinent site specific input data for the deterministic and probabilistic analysis: Site Latitude, Longitude: 34.0197, -118.5054 Vs30 – Shear Wave Velocity for upper 100 feet: 1,065 ft/sec (325 m/sec) The resulting preliminary ARS curve for the California Incline POC together with the digitized coordinates is presented in Figure 2. 6.0 Liquefaction Evaluation Liquefaction Potential. The liquefaction potential of the saturated, granular materials below the water table was evaluated using the procedures outlined by Seed et al. (1983) and updated by NCEER (1997) and Youd et al. (2001). Groundwater was encountered in all seven of the borings that extended below elevation +10 ft with recorded water table elevations varying between +1 and +9 ft. Groundwater was encountered in coarse grained material with SPT blowcounts greater than 50 blows per foot and in material considered non-liquefiable due to the abundance of fine- grained particles; therefore the liquefaction potential of the foundation materials is considered to be low. California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 5 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 Seismic Settlement. Seismically-induced settlement results from liquefied soils reconsolidating following excess pore pressure dissipation which occurs after earthquake shaking ceases. The extent of ground surface settlement depends on several factors such as characteristics of the soil, level and duration of shaking and extent of the liquefaction zone. Due to the dense consistency of the coarse grained material below the groundwater table and abundance of fine-grained particles at the site the potential for seismic settlement of the native foundation materials is considered to be negligible. 7.0 Global Slope Stability Static Stability. The Santa Monica Palisades have historically been prone to landslides with slides being recorded as early as 1884 (City of Santa Monica, 1988). Several geotechnical studies have been performed by the City of Santa Monica (1958, 1988) and consultants (Moran et. al, 1958, 1959, Mark Group, 1989) investigating the landslides and their causes within the Pacific Palisades, including the vicinity of the California Incline. The general conclusions of the studies are that the bluffs in the project vicinity are geologically very young and currently exist in an “oversteepened” condition. Based on bluff stability studies performed by URS Corporation (URS, 2006) and EMI (2013), in the vicinity of the California Incline POC, the bluffs above the incline roadway are currently considered “marginally stable” with a factor of safety between 1.0 and 1.2. Below the California Incline roadway in the vicinity of the subject POC, the bluff slopes are generally mild and have a factor of safety greater than 1.5 (EMI, 2013). As part of the California Incline Viaduct Replacement, soil nails are proposed above the Incline roadway to improve the stability of the bluffs above the Caltrans minimum required factor of safety of 1.5 for static stability. Details of the stability analysis and the soil nail stabilization are discussed in the Foundation Report for the California Incline Viaduct Replacement (EMI, 2013). Seismic Stability. The “global” stability of the existing bluff slopes under the pseudo-static condition was evaluated using the computer program GSTABLE7 (Gregory, 2006). Based upon strength parameters determined from field penetration and laboratory testing, using a seismic coefficient of 0.20, analysis indicates that the existing slopes below the California Incline roadway meet the Caltrans minimum required factor of safety of 1.1. Above the California Incline roadway, the proposed soil nail stabilization has been designed to improve the seismic stability of the upper bluffs above the Caltrans minimum required factor of safety of 1.1 (EMI, 2013). As a result, the bluff slopes surrounding the subject POC are expected to be seismically stable in a global sense; however localized and surficial raveling of soils that are saturated during periods of heavy rainfall or surface runoff may be experienced. 8.0 Scour Evaluation The California Incline POC does not cross a waterway and therefore scour potential is not expected to be a design issue. California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 6 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 9.0 Corrosion Evaluation Samples representative of soils throughout the project area were tested to determine corrosivity including minimum resistivity, pH, soluble sulfate content, and soluble chloride content. A total of eight soil samples from the EMI investigation were tested for corrosivity using the procedures described in California Test methods 417, 422, 532, and 643. According to Caltrans criteria (Corrosion Guidelines, 2012b), soils are corrosive if the pH is 5.5 or less, or the chloride concentration is 500 parts per million (ppm) or greater, or the sulfate concentration is 2,000 ppm or greater. Based on the test results, the on-site soils are considered to be corrosive to bare metals and concrete. 10.0 As-Built Foundation Data Existing Structure. The California Incline POC is an two-span reinforced concrete structure with an L-shaped deck (plan view). The main span of the structure runs in the east-west direction and crosses over the California Incline roadway. The main span is supported on its western end by a reinforced concrete staircase and on its eastern end by a reinforced concrete pier wall. After crossing over the eastern pier wall, the POC turns to the north and connects to a pedestrian trail cut into the bluffs above the California Incline Roadway. This eastern span is essentially a staircase that spans between the eastern pier wall and the southern end of the pedestrian trail (Idaho Pedestrian Trail) from the Palisades Park. All three supports are founded on 26-inch diameter Cast-In-Drilled-Hole (CIDH) piles. The western staircase is supported on four piles, the pier wall is supported on two piles and the northern landing for the staircase is a reinforced concrete slab supported on a single pile. Selected pages from the as-built plans for the POC are included in Attachment 2. Existing Structure Foundation. The as-built plans do not show a design service loading for the foundation piles. The four piles supporting the western staircase are shown as 43 ft long with an approximate pile tip elevation of -2 ft. The two piles supporting the eastern pier wall are shown as 35 ft long with a pile tip elevation of +5 ft. The single pile supporting the eastern staircase landing is shown as 35 ft long; however, the majority of its length is embedded in the bluff above the Incline roadway which has experienced significant erosion surrounding the pile. That pile has a tip elevation of +38 ft, approximately 5 ft below the Incline roadway. No design service loading is listed on the plans for any of the piles. Selected pages from the as-built plans for the POC are included in Attachment 2. 11.0 Existing Foundation Capacity Axial Pile Capacity. Axial capacity of a single CIDH pile supporting the western staircase and eastern pier wall was estimated to be 530 kips in compression and 290 kips in tension using the computer program SHAFT Version 6.0 (Ensoft, 2007). Piles supporting the western stair case and the eastern pier wall have a tip elevation near where groundwater was encountered in the recent EMI investigation; therefore, the nominal resistance was conservatively based upon skin friction only and no end bearing. For the piles supporting the western stair case, the skin friction in the upper 8 ft was also neglected to account for the sloping ground line descending from California Incline towards PCH. Due to the limited embedment of the single pile supporting the California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 7 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 eastern staircase landing below the California Incline roadway, the axial capacity is estimated to be 90 kips and be derived entirely from end bearing. The maximum pile-head settlement due to the nominal resistances is estimated to be less than ½- inch. The pile capacity is also based on soil resistance only and may be further limited by the pile-head connection details and the strength of the pile materials. Lateral Pile Capacity. LPile input soil parameters were provided to the designers for analysis of the lateral pile capacity and are provided in Table 2. Based on the pile layout shown on the as- built plans and the procedures outlined in the Ensoft Group 7.0 software Technical Manual (Ensoft, 2006), group reduction factors (P-Multipliers in the LPILE input) are not necessary due to the irregular pile layout and on-center pile spacing generally greater than 4.5 diameters. Table 2. LPILE Input Parameters P-Y curve Soil Model Elevation of Top of Soil Layer (ft) Elevation of Bottom of Soil Layer (ft) Effective Unit Weight (pcf) Friction Angle (Deg.) Cohesion (psf) k (pci) E50 P- Multiplier Stiff Clay w/out free Water (Reese) 75 35 120 0 2,500 0 0.005 1 Stiff Clay w/out free Water (Reese) 35 25 120 0 4,000 0 0.0025 1 API Sand (O’Neil) 25 5 120 36 0 160 0 1 API Sand (O’Neil) Below 5 - 57.6 36 0 95 0 1 12.0 Structure Foundation Retrofit Alternatives Based upon our conversations with the designers, it is our understanding that the foundations beneath the western staircase and the eastern pier wall have sufficient capacity to resist the seismic demands. However, due to the limited embedment below the California Incline roadway, the single pile supporting the eastern staircase does not have the required lateral capacity to resist the structural demands. Two different conceptual alternatives have been considered for the seismic retrofit; (1) providing some form of lateral restraint (i.e., tie-back ground anchors) near the upper portion of the existing pile and (2) removing the existing staircase and replacing it with a column supported staircase founded on a pile group embedded sufficiently below the California Incline roadway to provide the necessary lateral resistance. It is our understanding that the second alternative is the preferred alternative and that lateral demands on the piles will control the pile embedment. The LPile input parameters provided in Table 2 are recommended to determine the necessary pile embedment for the retrofit piles. California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 8 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 13.0 Additional Field Work/Laboratory Testing No additional field work or laboratory testing is currently planned. 14.0 References California Department of Transportation (Caltrans), 2009, Foundation Report Preparation for Bridges, December. ——, 2012a, Methodology for Developing Design Response Spectrum for Use in Seismic Design Recommendations, November. ——, 2012b, Corrosion Guidelines, Version 2.0; Office of Materials Engineering and Testing Services, Corrosion and Structural Concrete Field Investigation Branch, November. California Geological Survey, 1997, Seismic hazard zones, Topanga quadrangle: California Division of Mines and Geology, Official Map, April 1. California Geological Survey, 1997, Seismic hazard zone report for the Topanga 7.5-Minute Quadrangle, Los Angeles County, California: Division of Mines and Geology, Seismic Hazard Zone Report 01. Campbell, K., and Bozorgnia, Y., 2008, NGA ground motion model for the geometric mean horizontal component of PGA, PGV, PGD, and 5% damped linear elastic response spectra for periods ranging from 0.01 to 10 s.; Earthquake Spectra, Vol. 24, pp. 139-172. Chiou, B., and Youngs, R., 2008, An NGA model for the average horizontal component of peak ground motion and response spectra: Earthquake Spectra, vol. 24, pp. 173-216. Dolan, J. F., Sieh, K. E. (1991). Tectonic geomorphology of the northern Los Angeles basin: Seismic hazards and kinematics of young fault movement: in Ehlig, P. L., and Steiner, E. A., eds., Engineering Geology Field Trips: Orange County, Santa Monica Mountains, and Malibu, Guidebook and Volume, Association of Engineering Geologists. Earth Mechanics, Inc. (EMI), 2013, Foundation Report, California Incline Viaduct Replacement Project, EMI Project No. 02-112, In Preparation. Ensoft, 2007, SHAFT Version 6.0, A Program for the Study of Drilled Shafts under Axial Loading, Austin, Texas. Ensoft, 2010, LPILE Plus Version 6.0, A Program for Analyzing Stress and Deformation of a Pile or Drilled Shaft under Lateral Loading, Austin, Texas. Gregory, G., 2006, GSTABL7 with STEDwin Slope Stability Analysis System Program Manual, Version 2.005, California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 9 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 Mark Group, 1989, Preliminary Geotechnical Evaluation, California Incline, Santa Monica, California, Report No. 88-03183.28, February 23. Moran, Proctor, Mueser & Rutledge, 1958, Report on Phase 1 of Landslide Investigation, Pacific Palisades, California for State of California, Department of Public Works, May 1958. Moran, Proctor, Mueser & Rutledge, 1959, Final Report, Pacific Palisades Landslide Study, Volume 1-Text, Volume 2-Drawing, for State of California, Department of Public Works, July 1959. NCEER, 1997,"Proceeding of the NCEER Workshop on Evaluation of Liquefaction Resistance of Soils," T. L. Youd and I. M. Idriss Editors, Technical Report NCEER-97-0022, NCEER, Buffalo, NY. Santa Monica, City of, 1958, Summary of Landslides Occurring Along the Palisades Park Bluff within the City of Santa Monica from 1933 to 1958, September 1958. Santa Monica, City of, 1995, Safety Element of the General Plan, Technical Background Report. Santa Monica, City of 1988, Summary of Santa Monica Palisades Landslide Investigations 1933 through 1967, February 1988. Seed, H.B. and Harder, L.F., (1990), “SPT-Based Analysis of Cyclic Pore Pressure Generation and Undrained Residual Strength,” Proceedings, H. Bolton Seed Memorial Symposium, Vol. 2, Bitech Publishers, pp. 351-376. Shantz, T., Merriam, M., 2012 (In Preparation), Development of the Caltrans Deterministic PGA Map and Caltrans ARS Online, California Department of Transportation, Sacramento, CA. URS Corporation, 2006, Geotechnical study, Santa Monica Palisades Bluffs, Santa Monica, California: Unpublished Consultant’s Report to City of Santa Monica, Final Draft Report, Santa Ana, CA, February 24. U.S. Geological Survey (USGS), 2008a, Documentaion for the 2008 Update of the United States National Seismic Hazard Maps: U.S. Geological Survey Open-File Report 2008-1128, 61p. U.S. Geological Survey (USGS), 2008b, USGS Probabilistic Seismic Hazard Analysis, http:\earthquake.usgs.gov/research/hazmaps/ Youd, T. L. et al. (2001), “Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 127, No. 10, October. California Incline POC Preliminary Seismic Retrofit Evaluation Report October 10, 2013 Page 10 17800 Newhope Street, Suite B, Fountain Valley, California 92708 Tel: (714) 751-3826 Fax: (714) 751-3928 15.0 Attachments (1) California Incline Viaduct Replacement Project Log-of-Test-Borings (LOTB) Sheets (2) California Incline Pedestrian Overcrossing As-Built Plans Earth Mechanics, Inc. Geotechnical and Earthquake Engineering Project No. 13-138 Date: October 2013 Site Location Map Figure 1 CALIFORNIA INCLINE PEDESTRIAN OC Site Location N Spectral Coordinates: Period Acc. Period Acc. (sec) (g) (sec) (g) 0.00 0.632 0.85 1.210 0.10 1.109 1.00 1.154 0.20 1.374 1.20 1.009 0.30 1.379 1.50 0.836 0.40 1.307 2.00 0.597 0.50 1.304 3.00 0.345 0.60 1.283 4.00 0.233 0.70 1.264 5.00 0.179 Date: 5% Damping Project Number :13-138 Oct., 2013 Figure 2 Design ARS Curve Peak Ground Acceleration = 0.632 g Shear Wave Velocity (Vs30) = 325 m/s Lattitude: 34.0197 Longitude: -118.5054 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0Spectral Acc. (g)Period (s) Earth Mechanics, Inc. Geotechnical and Earthquake Engineering CA Incline POC Design Acceleration Response Spectrum ATTACHMENT 1 CALIFORNIA INCLINE VIADUCT REPLACEMENT PROJECT LOG-OF-TEST-BORINGS SHEETS ATTACHMENT 2 CALIFORNIA INCLINE PEDESTRIAN OVERCROSSING AS-BUILT PLANS