Design and Response of Lower-Level Beam-Column Joints in Ductile ReinforcedConcrete Double-Deck Bridge Structures

摘要

A research program of field and laboratory tests to study the seismic response ofreinforced concrete double-deck freeway structures has been concluded at the University of California, Berkeley. The third phase of testing focused on the design criteria for beam-column joints in new ductile double-deck freeways. This report describes the research finding of the third phase of the program. Two one-third scale test specimens representing the lower-level beam-column joint in a double-deck bridge structure were built and tested in the laboratory. The test specimens were designed according to current design criteria. The two tests specimens differed in the strength of the members framing into the joints. This difference in strength resulted in a difference in maximum demands on the beam-column joint at the member interfaces. The scope of the tests was to determine the response of the joints when subjected to unidirectional and bidirectional load cycles and compare the response to the different levels of maximum joint shear stress demands. The test specimens were able to sustain the design forces and deformations without significant distress in the joint. Most of the deformation and damage concentrated at the column ends.