帶狀桁架結構之最佳位置分析

Abstract

本文主要在分析均勻的帶狀桁架結構系統，其結構行為與減低結構側向位移的效率。靜力分析時，考慮結構受兩種水平負載，在結構構件（剪力牆、帶狀桁架、內柱）剛度比值不同的情況下，以單位力法及變形諧和的觀念，分析具一至四層帶狀桁架結構在結構頂層側移最小時帶狀桁架的設置位置，及帶狀桁架數量對減少側移的有效度；動力分析則是考慮一層帶狀桁架結構最大的第一振頻下的帶狀桁架設置位置。研究的結果發現，不管在靜力分析或是動力分析下，將帶狀桁架平均設置在結構的高程上可得近似的最佳位置，且帶狀桁架的撓曲剛度相對於剪力牆越大時，帶狀桁架的最佳位置越低。而分別考慮結構在靜力與動力分析下，受倒三角形載重下的帶狀桁架最佳位置較高，其次為受均佈載重時，最大的第一振頻下帶狀桁架的位置則最低。

The behavior of the belt-truss structure with two core structures is presented. The main feature of the system is to reduce the lateral displacement of building structures while subjected to horizontal loading. In static analysis, it is considered that the structure with different relative rigidities between structure members (shear wall, belt-truss, inner column) is subjected to two kind of horizontal loading (uniform and inverse triangular distributions). Using unit load method and the condition of displacement compatibility, the optimal locations of belt-truss for smallest displacement at top of building structures are calculated. In dynamic analysis, it is considered that the optimal locations of belt-truss for the highest fundamental natural frequency. It is concluded that the optimal locations of the belt-trusses are approximately equidistant height of the building structures. Also, the stiffer belt-truss are, the lower are the optimal locations of belt-truss . The optimal locations while subjected to triangular distributed loading is higher than the one that are subjected to uniform distributed loading, and the optimal locations in static analysis is also higher than that in dynamic analysis.