Simplified Procedures for Seismic Analysis and Design of Piers and Wharves in Marine Oil and LNG Terminals

: This investigation developed simplified procedures for the seismic analysis and design of pile supported wharves and piers in Marine Oil and LNG Terminals. A simplified coefficient-based approach is proposed for estimating seismic displacement demand for regular structures. This approach is adopted from the performance-based analysis procedure recently approved for buildings in the ASCE/SEI 41-06 standard (ASCE, 2007). A modal pushover analysis (MPA) approach is proposed for irregular structures. The MPA procedure accounts for the higher-mode effects that are important in irregular structures (Chopra and Goel, 2004). The acceptability of piles in terms of displacement ductility limitation, instead of the material strain limitation, is proposed. For this purpose, simplified expressions for estimating displacement ductility capacity of piles are recommended. These expressions are calibrated such that the material strain limits in Title 24, California Code of Regulations, Chapter 31F, informally known as the Marine Oil Terminal Engineering and Maintenance Standards (MOTEMS), would not be exceeded if the displacement ductility demand is kept below the proposed displacement ductility capacity. These simplified procedures can be used as an alternative to the procedures currently specified in the MOTEMS. The simplified procedures can be used for preliminary design or as a quick check on the results from detailed nonlinear analyses. The more sophisticated analysis methodology can still be used for final design. The following is a summary of the procedures to estimate displacement demands and capacities for pile-supported wharves and piers.