96-0006 Establish Representative Pier Types for Comprehensive Study - Western United States R. Imbsen, R. Schamber and T.A. Osterkamp 1996 Imbsen & Associates, Inc. 100 PB98-118607 15 This report describes bridge pier types and seismic design and detailing procedures for new construction typical of the western U.S. since the mid-1970s. The companion report, NCEER-96-0005, describes pier types and seismic design and detailing procedures representative of the eastern U.S. since about 1980. Representative bridge types and pier type details for nine western states are referenced in Section 2. The states contributing material include Alaska, Arizona, California, Idaho, Montana, Nevada, Oregon, Wyoming and Washington. Section 3 of the report includes column and pier design and detailing issues which include: column spiral reinforcement; column shear reinforcement within the outside potential plastic hinge zones; spirals, hoops or tie requirements into bent caps and footings of fixed columns; column reinforcement lap splice restrictions; column reinforcement recommendations into knee joints; modification of linearly elastic seismic forces by R or Z factors; multi-column bent and pier wall foundation supports; column flares reinforced with minimal transverse and longitudinal reinforcement; fully confined column flares; distinction between a column and pier wall; pier wall confinement reinforcement; and partial height pier walls. Section 4 of the report includes bent cap detailing issues and Section 5 footing detailing issues. Section 6 addresses construction material issues. Spiral Reinforcement, Highway Bridges, Bent Caps, Reinforced Concrete Bridge Piers, Western United States, Reinforced Details, Footings, Construction Materials, Plastic Hinges, and Lap Splices.