振動台実験経験後の鉛ブラグ入り積層ゴムの損傷と残存性能の評価: E-デイフェンス振動台実験による免震構造物の終局時挙動の解明 その2

摘要

本研究では，破断レベルのひずみを経験した積層ゴムの損傷と残存性能を明らかにするため，免震システムの振動台実験で破断した積層ゴムの破断面の観察，並びに未破断であった積層ゴムの静的試験，切断面の観察および材料試験片によるせん断試験とピーリング試験を行った。各検討では，振動台実験を経験していない積層ゴムの試験結果を比較対象としながら考察を行った。本検討で得られた知見は以下の通りである。%This paper presents damage and structural performance of lead rubber bearings which experienced shaking table tests on seismic isolation systems. During the shaking table tests, some of the bearings ruptured due to excessive shear deformation. After the teste, failure surfaces were observed to confirm that these failures started at not bond layers but rubber sheets. Static loading tests were conducted on bearings without rupturing to evaluate structural performance before and after the shaking table tests. Then these bearings were cut in the main loading direction to observe inner damage. In addition, test pieces were made from these bearings to perform shear material teste and peeling tests. It was found that, although inner damages of the rubber and steel were observed around lead plugs, fundamental performance of the bearings was less deteriorated even after the shake table tests.