The new reinforced concrete structural system, referred to hinge isolated structural system (RCHIS), has been developed in order to mitigate damage of RC members. The system has the un-bond longitudinal steel bars and supplementary unanchored steel bars at the hinge region of the members. Therefore, the major damage is limited to the end of the members. Seismic tests showed their outstanding structural performance of members. This paper discusses a reparability performance of RCHIS beams after damage. The test results prove that repaired RCHIS beams indicate almost the same deformation capacity, mitigated crack patterns and stress-transfer mechanism as the original one, and that RCHIS beams are more reparable than conventional RC beams.

In the strengthening method for R/C buildings proposed by authors, steel frame is connected to the existing R/C frame through indirect joint. Experimental study was conducted, and the observed results suggested that that the steel frame restrains the increase of crack width of R/C column caused by reversal loading, and the strengthening effect can be performed without anchors in indirect joint of column. In order to support this finding theoretically, 3D FEM analysis is applied for shear failure R/C specimen. In this paper, it is discussed about the results of analysis and evaluation of stress transfer mechanism of indirect joint.

The test results of the hinge isolated shear walls (called as HISS RC walls) showed slip phenomena at the wall in the large deformation range after flexural yielding. If their slip phenomena had been restricted, they, obviously, could have had stable energy absorption capacity. This paper reports the details of slip phenomena in terms of load-displacement relationships and vertical displacements at the wall bottom. Considering dowel behavior, the slip stiffness at the load zero can be modeled using pile registration formulae. The ratio of the flexural stiffness to the slip stiffness is an effective index to assess the effect of slip phenomena after flexural yielding on energy absorption characteristics.

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Seismic reinforcement by Passive Control System is dynamic design, it's a performance evaluation of buildings due to drift angle. That is why, it is difficult to evaluate with current seismic index of Structure. In this paper, we propose a method for calculating the conversion index that to evaluate the dynamic performance. In addition, considering the correction factor the converted seismic index of Structure. Then, we discuss the relationship between level and the conversion index affected.