1 Page Write-up for Geotechnical Deliverables

Foundation Design

For the abutment and footing design, soil analysis was required to determine allowable design loads. Our geotechnical engineers have provided a thoroughly soil reports and calculations for the abutment and is located in Appendix XX. With our design constraints, our structural engineers have come to concluded that spread footing design is best for our pedestrian bridge.

Design Criteria

Based on the geotechnical reports, our structural engineers have designed our abutment and footing to transfer the loads from the pedestrian bridge to the underlying soil and to prevent the soil from tipping the abutment over. Our structural team have worked closely with our geotechnical team to design an abutment that capable to support a 144 Kips (Dead + Live) loads coming from the bridge, and to not exceed the bearing capacity of 4000 psf. With the vertical depth of the abutment and footing of 26 ft, our teams already take into consideration that our footing need to be 3 ft below the channel to prevent the soil erosion below the footing. Our abutment and footing will be design for overturning moment and shear coming from soil pushing into the abutment wall. All stresses have been accounted for and designed to be able to handle the above mentioned stresses, all calculations are included in Appendix XX. Both abutment and footing are the same on both end span of the bridge.

Our structural engineers will use 4000 psi concrete, and 60000 psi steel for the abutment and footing design. The abutment dimensions will be 15 ft wide by 24 ft height and thickness of 4 ft. The footing will have dimensions of 15 ft wide by 2 ft depth a thickness of 12 ft.

With the dimensions of abutment and footing calculated, the righting moment created by reinforced concrete is much larger than the overturning moment pushing against it and is adequate for the bridge support.