以基因演算法進行鋼結構最佳化設計之研究

Genetic Algorithm on Optimum Design of Steel Structure

陳俊佑(Chun-Yu Chen 陳俊佑)

指導教授 ： 宋裕祺

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2013年)

摘要

傳統的鋼結構設計大多採用試誤法設計其斷面，雖然符合規範之要求，但是不能確保是否為最適合之斷面，所以本研究利用基因演算法針對鋼結構進行最佳化設計，目的是為了使鋼構架輕量化進而達到經濟性之效果。
在基因演算法中，設計之變數為AISC-LRFD設計手冊中W型鋼斷面，梁柱構材限制條件為：(1)應力比限制：為需求強度與設計強度之比值，包含軸力與彎矩其總和不得大於1.0，為避免鋼材斷面過大造成自重增加影響成本，因此將應力比下限限制在0.8以上確保斷面最佳化；(2)樓層位移：符合AISC-LRFD規範之規定，即單一樓層高度之 或總樓層高度之 及(3)梁構材之中點位移：符合AISC-LRFD規範之規定，即梁跨之 。
本研究模擬並撰寫基因演算法程式，搭配結構分析軟體SAP2000提供之API (Application Programming Interface，簡稱API)功能，可控制SAP2000自動更換斷面來取代試誤法，不但可以節省斷面替換所需的時間且達到自動化之效果。
研究成果顯示，本研究所得結果確可達到鋼結構設計最佳化之目標，且本研究結合基因演算法與SAP2000所撰寫之程式亦可發揮預期功能，可供為業界從事鋼結構設計之用。

關鍵字

SAP2000 ； 基因演算法 ； 鋼結構 ； AISC-LRFD ； 自動化

並列摘要

Traditional structural steel design is probably completed by trial and error method. The design result may satisfy the requirements of design code but not always match the optimum outcome, depending on the engineers’ experience. In order to have an optimal design, this thesis intends to combine the genetic algorithm (GA) into steel structural design.
In the optimization model, minimization of weight of the steel member used was adopted as the objective function (OF). The constraints including stress-ratio, story drift ratio and deflection at midpoint of beam were arranged as penalty function to OF. This thesis developed GA process to deal with the optimum solution.
The Application Programming Interface (API) provided by software of SAP2000 was employed to connect GA process developed. The automatic switch between SAP and GA can be achieved and enrich the design efficiency.
The results obtained in this thesis can benefit structural engineers an optimal design of steel structure with high precision and efficiency.

並列關鍵字

SAP2000 ； genetic algorithm ； steel structure ； automatic

參考文獻

[41] 連立川、葉怡成、鄭明淵，「以遺傳演算法及運算樹作高性能混凝土強度建模」技術學刊，第二十一卷，第一期，2006，pp.41-54。

[1] Adeli H., Kumar S.”Distributed Genetic Algorithm for Structural Optimization,” J. of Aerospace Engineering, Vol. 8, No. 3, 1995, pp. 156-163.

[2] Camp C., Pezeshk S. and Cao G."Optimized design of two-dimensional structures using a genetic algorithm.", Journal of Structural Engineering, Vol. 124, No. 5, 1998。

[3] Castro L. C. L. B. d. and Partridge P. W."Minimum weight design of framed structures using a genetic algorithm considering dynamic analysis.", Latin American Journal of Solids and Structures, Vol. 3, 2006, pp. 107-123。

[5] Díaz C., Victoria M., Querin O. M., Marti P."Optimum design of semi-rigid connections using metamodels.", Journal of Constructional Steel Research, Vol. 78, 2012, pp. 97-106。