2002年の倉庫業法の改正や流通サービスの増加等を背景として， 物流倉庫の着工面積が増加している。近年は，トレーラートラッ クが自走できるランプウェイを設けた大型倉庫が増加するとともに, スラブ用積載荷重も増加している。しかし，倉庫建築物は設備や仕 上げ等の費用が低いため，工事単価の平均値は他の用途の建築物に 比べて低い。また，物流業の業績は景気動向と緊密に連動するた め，低迷している近年の景気を反映して倉庫建築物に対する建設コ スト縮滅の要請が強い。そのため，倉庫建築物には建物の安全や地 震時における在庫の保全を担保しつつ，設計数量の低減が求められ る。一方，取扱い荷物や建築物の保全を目的として免震構造や制震 構造を採用した倉庫も増加しているが建設費も増加するため，低コ ストで荷物や建築物の地震応答を低減できるシステムが求められて いる。%Some experiments of the seismic response reduction using loads slipping related to the experimental frame and loads were conducted in the previous studies. However, damping factors of these frames are lower than the average damping factor of the general structure. In this paper, relationships between the loads slip effect (LS0 and the damping factor were analyzed As a result, LSE was decreased according to the increase of damping factor of structure. Therefore, the shaking table tests on a simple one-story frame model were carried out to obtain the basic characteristics of LSE using various parameters including damping factor. Prom the shaking table tests, following results were obtained, LSE was increased by decreasing coefficient of friction of load, by increasing maximum velocity of input seismic motion, by increasing the mass ratio, and LSE was decreased by increasing damping factor. The results show that first natural frequency of the frame becomes higher as the LSE is increased. Also damping factors (h_(ep) of the frame that allow loads to slip were estimated using displacement response spectrum, and h_(eq) is higher as the LSE is increased.
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