Experimental Study On Seismic Behavior Of Buckling-Restrained Brace Concrete Frame

Buckling-Restrained Braces (BRB) is a new type of brace that has a good energy dissipation ability, comparing to the traditional brace, it is a complementarity which could not be buckling under the compression. Application in concrete structure is less than steel structure in the experimental study and new construction. For historical and practical reasons, concrete structures in existing and new buildings are occupying an absolute number of percentages in China. Therefore, establish a calculation method and design theory which not only follow its own scientific laws but also meet the provisions of the existing seismic specification, has important engineering significance and practical value to impel BRB is widely used in China.Three BRB concrete frames (BRBCF) are design and tests, according to seismic design of our research group, basis on theoretical and experimental research at home and abroad. Three BRBCFs with different BRB or beam sections are designed, manufactured and tested under reversed cyclic loadings. Seismic performances, such as concrete element cracks, lateral load-displacement loops, skeleton curves, tangent stiffness and its deterioration, and BRB load-deformations, forces of concrete joints and the embedded parts, etc, are studied. Test result shows that the BRB and concrete frame cooperate soundly in resisting lateral force, and the system have rich and stable hysteric load-displacement curves. The BRB can start yielding at relatively lower story drift ratio, and also keep effective at large lateral drift angle. It validated that the equivalent viscous damping can thus be increased and the seismic response be reduced, and then the structural performance be improved. The designed concrete joints, the embedded parts and the connectors function well and reliably. It is validated that the BRBs are applicable in concrete frame. It provides a reliable test data for BRB technology used in concrete frame. It not only use for seismic design of BRBCF but also provides references for seismic retrofit of homogeneous structure.