Tomoya Matsui

SEISMIC PERFORMANCE OF RC FRAME RETROFITTED BY CES PORTAL FRAME

This research deals with a seismic retrofitting technique of installing CES portal frames to an existing RC frame building. One of characteristics in the retrofitting technique is to employ the precast construction method that precast CES members are connected at the middle of the beam and columns of the portal frame. This retrofitting technique also uses both the adhesive joint method and the post-installed anchoring method to unify the existing RC frame and the installed CES frame. Static loading tests were conducted for a total of four one-bay one-story frames including one bare frame and three retrofitted frames with the experimental parameter of connection details between the existing RC frame and the installed CES frame. Dynamic loading test was also carried out to compare the dynamic behavior with the static behavior of the retrofitted frames. This paper outlines the testing and presents the effect of the installed CES portal frame on the seismic performance of the retrofitted RC frame.

STRESS TRANSFERRING MECHANISMS OF COMPOSITE CES BEAM-COLUMN JOINTS UNDER LATERAL LOAD REVERSALS

In this study, three dimensional non-linear FEM analysis of beam-column joints for composite CES structural systems is conducted to verify applicability of the analysis method and modeling, together with examining the stress transferring mechanism for the CES joints. The analytical results show good agreement with the experimental ones on the story shear versus story drift response for the CES joints, namely it is found that the behavior of CES beam-column joints can be approximately simulated by the analytical method. It is confirmed that analyzed shear force in the outer concrete without steel are contributed as almost the same level as those in the inner concrete surrounded by the steel flange of the beam and column at the maximum capacity of the beam-column joint. It is also shown that the ultimate shear strength of the CES beam-column joints can be evaluated by a method based on the AIJ design standard for SRC structures.