Figure B Maximum bending moment and shear vs. pile length. 0 20 40 60 80 100 120 140 600 620 640 660 680 700 720 740 760 780 800 10 15 20 25 30 35 40 45 Maximum She ark ip) M ax im um B endi ng M om ent ( ki p- ft) Pile Length (ft) Pile Lateral Deflection vs Pile Length (Strength Loads) Maximum Moment Maximum Shear B.2 PILE GROUP LATERAL ANALYSIS FOR DESIGN OF ABRIDGE PIER This examples presents a lateral analysis of abridge pier foundation consisting of a group of 4 foot diameter driven close ended pipe piles filled with concrete. This example is supported by analyses performed with the computer program GROUP. The bridge pier and its foundation system are shown in Figure B. Due to the nature of the loading, a three-dimensional analysis (Dis performed (longitudinal and transverse directions. Step 1: Determine Idealized Soil Profile and Geotechnical Design Parameters The first step consists of the determination of an idealized soil profile based on the results of the subsurface investigation program. Presenting a detailed evaluation of the subsurface investigation program goes beyond the scope of this manual, and therefore is not presented in detail herein. The assumed idealized soil profile and geotechnical design parameters are summarized in Table B. The top of pile and groundwater level are 7 feet below the ground surface. In this example, it is determined that no potential for liquefaction, lateral spreading, or lateral flow exists, therefore the same parameters shown in Table B can be used to assess all the Limit States being considered (Service, Strength and Extreme.
243 Figure B Example problem B. Table B Interpreted soil parameters. Layer Nob bSoil Type Model Depth* (ft) Φ (deg) Su (psf) γ' (pcf) k s ** (pci)
