A Case Study on Earthquake Resistant Reinforcement Method for the Corner of Existing Underground R.C Box Structures using Pre-flexed Member System

프리플렉스 부재를 이용한 기존 철근콘크리트 지중박스구조물 우각부에 대한 내진보강공법 사례연구

  • Received : 2016.01.11
  • Accepted : 2016.04.05
  • Published : 2016.06.30


This paper presents a new strengthening method of underground box structures against seismic loads for anti-seismic capacity improvement. A threaded steel member with pressure devices(so called 'Pre-flexed member system') is used to improve seismic capacity of the RC box structure. The pre-flexed member system is fixed the corner of opening after chemical anchor was installed by drilling hole on the box structure. The structural performance was evaluated analytically. Two bracing types of strengthening methods were used; conventional bracing method and I-bracing pressure system. For the performance evaluation, seismic analyses were performed on moment and shear resisting structures with and without strength member system. Numerical results confirmed that the proposed pre-flexed member system can enhance the seismic capacity of the underground RC box structures.


underground box structures;anti-seismic capacity;pre-flexed member


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  1. Strength Method Using Pre-flexed Members for the Corner of Underground Box Structures under Additional Surface Load vol.31, pp.5, 2016,