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3.2 — Preliminary Geotechnical Engineering Analysis <br /> 3.21 — Generate AASHTO Seismic Design Parameters <br /> Based on the geologic cross-section along the bridge alignment, HWA shall determine the Site <br /> Class for seismic design. The design spectral acceleration parameters shall then be selected in <br /> accordance with the AASHTO Guide Specifications for LRFD Seismic Bridge Design. <br /> 3.22 — Evaluate Soils for Liquefaction and Lateral Spread Potential <br /> HWA shall evaluate the susceptibility to liquefaction of the materials along the bridge alignment <br /> for the design event required by AASHTO. Once the susceptibility to liquefaction is determined, <br /> we shall evaluate the potential for lateral spreading. <br /> 3.23 — Evaluate Slope Stability at the Abutments <br /> Global stability of the subsurface soils shall be evaluated at the abutments. Global stability shall <br /> be evaluated using limit equilibrium methods consistent with the WSDOT GDM. <br /> 3.24 — Evaluate Bridge Foundation Vertical Capacity <br /> HWA shall perform analyses of foundation vertical capacities using accepted drilled shaft <br /> estimation methods provided in the AASHTO LRFD Bridge Specifications and the Washington <br /> State Department of Transportation (WSDOT) Geotechnical Design Manual (GDM). <br /> 3.25 — Evaluate Bridge Foundation Lateral Capacity <br /> HWA shall develop bridge foundation lateral parameters. The lateral parameters shall be <br /> provided in the form of LPILE input parameter tables for the various soils units. <br /> 3.26 — Generate Abutment Lateral Earth Pressures <br /> HWA shall provide lateral earth pressure recommendations for proposed abutment structures <br /> and wing walls. Earth pressure diagrams for both static and seismic loading conditions shall be <br /> generated using the procedures outlined in the WSDOT GDM. <br /> 3.27 — Pavement Design Sections <br /> HWA shall provide pavement design sections for new areas of pavement along Grand Avenue. <br /> HWA will use the 1993 AASHTO Design Guide to develop pavement design recommendations <br /> using traffic counts provided by KPFF. <br /> 3.28 — Generate Preliminary Geotechnical Report <br /> HWA's geotechnical report shall contain the results of the geotechnical engineering <br /> investigation, including description of surface and subsurface conditions; a site plan showing <br /> exploration locations and other pertinent features; summary boring logs; and laboratory test <br /> results. The report shall provide a narrative and geotechnical recommendations for each of the <br /> above described geotechnical aspects of the project. <br /> 3.3 — Preliminary Geotechnical Engineering Environmental Support <br /> 3.31 — Complete Groundwater Monitoring <br /> HWA shall install groundwater monitoring transducers in each proposed monitoring well. These <br /> transducers will be set to take groundwater elevation readings every half an hour for the <br /> duration of 1 year. A Hydrogeologist from HWA shall make quarterly site visits to download and <br /> process the groundwater data. This data will be used to provide prospective contractors with an <br /> accurate representation of the seasonal groundwater variations across the site. <br /> KPFF Consulting Engineer November 10, 2014 <br /> Grand Avenue Park Utility Bridge, Phase 1A Page 13 of 55 <br />