USE OF GRADED COMPOSITE STRANDS IN PCAPC STRUCTURES FOR BETTER SEISMIC PERFORMANCE
When major earthquakes hit urban areas in the world in 1990s and 2000s, many damaged reinforced concrete buildings did not function continuously during a long term repair period. Base isolation is one of the solutions to reduce the seismic damage and prevent the out-of-service state, but it needs high initial and maintenance costs and cannot be applied to every building. This study aims to propose an economical structural system with precast prestressed concrete (PCaPC) structures. PCaPC structures need no or little repair after earthquakes due to their self-centering characteristics. However, they also show excessive lateral deformations under earthquakes because of their low stiffness and small energy dissipation capability. The authors proposed to use graded composite strands (GCS-U) which has both characteristics as a tendon and an energy dissipating element. A GCS-U consists of seven high yield strength wires surrounded by twelve low yield strength wires. In an experimental phase, cyclic loading test on three PCaPC portal frames with different types of tendons (GCS-U, ordinary strands with or without bond) were conducted. The specimen using GCS-U showed larger amount of energy dissipation as the specimen using unbonded strands. All specimens showed and almost no damage until 2% story drift. In an analytical phase, envelope curves of experimental lateral load-drift relations were simulated accurately with a frame analysis model. It is confirmed that PCaPC structures with GCS-U have high possibility to provide economical damage-free buildings.
Precast prestressed concrete structures Graded composite strand Residual deformation Energy dissipation Flag shape hysteresis loop
Naosuke RYU Yukako ICHIOKA Minehiro NISHIYAMA Susumu KONO Fumio WATANABE
Dept. of Architecture and Architectural Engineering, Kyoto University, Kyoto. Japan Dept. of Urban and Environmental Engineering, Kyoto University, Kyoto. Japan
国际会议
14th World Conference on Earthquake Engineering(第十四届国际地震工程会议)
北京
英文
2008-10-12（万方平台首次上网日期，不代表论文的发表时间）