含鋼板阻尼器構架最佳化設計

Optimization of Steel Panel Dampers for Moment Resisting Frame Designs

張舉虹(Chu-Hung Chang) ； 蔡克銓(Keh-Chyuan Tsai)

《結構工程》 34卷1期 (2019/03) Pp. 27-56

https://doi.org/10.6849/SE.201903_34(1).0002

摘要

鋼板阻尼器（Steel Panel Damper，SPD）為三段式寬翼構件，中段為非彈性核心段，上下兩段為彈性連接段，在核心段配置加勁板，可延遲受剪挫屈的發生。在抗彎構架配置SPD，核心段腹板能反覆受剪降伏來消能，本研究利用MATLAB最佳化工具箱，結合模擬退火法與梯度下降法成混合式演算法，考慮上下層SPD相同且皆於梁跨中心，僅探討SPD、邊界梁與其交會區之設計，以最少SPD、加勁板、邊界梁全長、交會區疊合板與連續板總用鋼量為目標函數。SPD、加勁板、邊界梁斷面與交會區疊合板厚為設計變數；以滿足SPD、邊界梁與交會區容量設計、SPD核心段加勁板設計及防止斷面局部與側向扭轉挫屈作為基本限制條件，研究最少用鋼量為「基本設計」。因SPD勁度強度可分離，在固定強度下可增加勁度，然增加SPD或邊界梁勁度，皆能提升構架勁度，本研究根據反曲點取出SPD與邊界梁十字子構架，在選定SPD強度下，以子構架側向勁度增加50％為新增限制條件，再次進行最佳化設計，稱所得最少用鋼量為「1.5倍勁度設計」。設計範例顯示在滿足基本限制條件下，只須增約9%用鋼量，即可達1.5倍勁度設計。為提高勁度，主要以增加邊界梁深與腹板厚較有效，但將導致梁強度增加40%。另對梁強度增量設25%上限，發現須較基本設計增約11%用鋼量，才可得1.5倍勁度設計。若另對梁深也設上限，須增約30%用鋼量，才可得1.5倍勁度設計；此時梁強度為基本設計的1.2倍。本研究也討論垂直載重對邊界梁設計之效應，並表列實際可供工程應用之最佳化SPD與邊界梁的設計尺寸案例。

關鍵字

鋼板阻尼器 ； 耐震設計 ； 容量設計 ； 受剪挫屈 ； 最佳化設計 ； 抗彎構架

並列摘要

The proposed 3-segment steel panel damper (SPD) consists of one middle inelastic core (IC) and two end elastic joint (EJ) wide-flange sections. During earthquakes, the two EJs of the same cross-sectional property, are designed to remain elastic while the IC could undergo large inelastic shear deformation thereby dissipating seismic energy. In order to sustain a large deformation and delay the shear buckling of the IC web, stiffeners must be properly devised. In this study, optimization algorithm is adopted to proportion the SPDs and the boundary beams, and achieve the minimum steel weight design. It is assumed that two identical SPDs, one above and one below, are attached to the boundary beam mid-span. The MATLAB optimization toolbox combined the simulated annealing algorithm with the gradient-descent method is adopted to find the minimum steel weight design. The objective function is the total weight of the SPD, the boundary beam and the panel zone. The design variables are the sectional properties of the SPD, the boundary beam and the doubler plate thickness. Constraints include the capacity design of the SPD, boundary beam and panel zone, the stiffeners of the IC web, compact section and lateral torsional buckling limit state design requirements. The ＂basic design＂ is the lightest sections meeting all the constraints. The lateral stiffness of the two SPDs- to-boundary beam subassembly can be enhanced by either increasing the stiffness of the SPDs or the boundary beam. As examples, the optimization designs of increasing 50% more stiffness of the subassemblies as the new constraint were conducted also. While complying with the aforementioned constraints, the steel weight is increased by about 9% to achieve a 50% more stiffened design. The stiffness of the subassemblies are found enhanced most effectively by increasing the beam depths and web thicknesses.

並列關鍵字

steel panel damper ； seismic design ； capacity design ； shear buckling ； optimization design ； moment resisting frame