Search

The purpose of this paper is to propose a practical method for optimum design of oil dampers with relief mechanism installed in multi-story buildings. The optimum design problem is formulated so as to minimize the maximum interstory drift under design earthquakes in terms of a set of relief forces subject to an inequality constraint on maximum ratio of the damping force to the relief force and an equality constraint on sum of relief forces of oil dampers. The proposed method to solve the optimum design problem is a successive procedure which consists of two steps. The first step is a sensitivity analysis including nonlinear time-history analyses, and the second step is a modification of the set of relief forces based upon the sensitivity analysis. Numerical examples are conducted to present the effectiveness and validity of the proposed design method., Transactions of AIJ. Journal of structural and construction engineering

A model reduction method is proposed for an elastic high-rise building with viscous dampers subjected to earthquake ground motion. A set of story stiffnesses of the reduced model is found under the equivalent conditions that the original model without dampers and its reduced model possess the same fundamental natural frequency and fundamental mode shape. A reduced model of the time-dependent earthquake inertia force is also proposed by requiring the equivalence of displacements at representative floor levels in both models without inertia and damping terms. A set of damping coefficients and a set of relief loads of bilinear-type viscous dampers of the reduce model are found under the equivalent conditions that the original model with dampers and its reduced model possess the same lowest-mode damping ratio and energy dissipation mode shape. Numerical examples are presented to demonstrate the efficiency and accuracy of the proposed method. It is concluded that the proposed method can substantially reduce the number of degrees of freedom in the time history analysis within an acceptable accuracy., Transactions of AIJ. Journal of structural and construction engineering

application/pdf, 2001年度香川大学公開講座「〈中小企業経営セミナー〉新たな地域の自立と連携のあり方を探る―21世紀の四国像の展望―」（2001年11月6日～12月3日、全5回、高松商工会議所・(社)高松法人会との共同主催）の内容を論稿としてまとめたもの。

application/pdf, 2001年度香川大学公開講座「〈中小企業経営セミナー〉新たな地域の自立と連携のあり方を探る―21世紀の四国像の展望―」（2001年11月6日～12月3日、全5回、高松商工会議所・(社)高松法人会との共同主催）第3部の内容を論稿としてまとめたもの。

Summaries of technical papers of Annual Meeting Architectural Institute of Japan. B-1, Structures I, Loads, reliability stress analyses foundation structures shell structures, space frames and membrane structures

The purpose of this paper is to propose a practical method for optimum design of oil dampers with relief mechanism installed in multi-story buildings. The optimum design problem is formulated so as to minimize the maximum interstory drift under design earthquakes in terms of a set of relief forces subject to an inequality constraint on maximum ratio of the damping force to the relief force and an equality constraint on sum of relief forces of oil dampers. The proposed method to solve the optimum design problem is a successive procedure which consists of two steps. The first step is a sensitivity analysis including nonlinear time-history analyses, and the second step is a modification of the set of relief forces based upon the sensitivity analysis. Numerical examples are conducted to present the effectiveness and validity of the proposed design method.

A model reduction method is proposed for an elastic high-rise building with viscous dampers subjected to earthquake ground motion. A set of story stiffnesses of the reduced model is found under the equivalent conditions that the original model without dampers and its reduced model possess the same fundamental natural frequency and fundamental mode shape. A reduced model of the time-dependent earthquake inertia force is also proposed by requiring the equivalence of displacements at representative floor levels in both models without inertia and damping terms. A set of damping coefficients and a set of relief loads of bilinear-type viscous dampers of the reduce model are found under the equivalent conditions that the original model with dampers and its reduced model possess the same lowest-mode damping ratio and energy dissipation mode shape. Numerical examples are presented to demonstrate the efficiency and accuracy of the proposed method. It is concluded that the proposed method can substantially reduce the number of degrees of freedom in the time history analysis within an acceptable accuracy.