模糊遺傳演算法在橋梁耐震性能設計之應用與耐震維修補強生命週期成本最小化之研究

Fuzzy-genetic Optimization on Performance-based Seismic Design and Study on Minimization of LCC in Seismic Retrofitting of the Bridges

蘇進國(Chin-Kuo Su)

指導教授 ： 宋裕祺

國立臺北科技大學/工程學院/工程科技研究所/博士(2008年)

摘要

本研究旨在研擬一模糊遺傳演算法來處理具有限制條件之最佳化設計問題，並將其應用於以結構性能為基準之橋梁耐震性能設計。此外，本研究亦針對橋梁耐震維修補強之生命週期成本最小化分析提出具體的分析程序。
本研究以模糊理論控制遺傳演算法中的懲罰函數，有效求解含約束條件的最佳化問題。研究除建立一套模糊遺傳演算法之分析流程外，並具體開發相關應用分析程式，續以最佳化文獻刊載之數學函數和桁架最佳化設計等問題進行程式之驗證與探討。
為將模糊遺傳演算法成功應用於橋梁耐震性能最佳化設計之中，本研究先引用國內外相關研究機構所進行的十四組橋墩反覆載重實驗所得之容量曲線、三組橋墩反覆載重實驗所得之遲滯迴圈與兩組橋墩擬動態試驗成果等資料，進行橋梁耐震性能評估之研究，再繼以三組不同斷面形式的實驗成果，就文中所提模糊遺傳演算法應用於橋梁耐震性能設計之正確性進行驗證。在全橋耐震性能設計方面，為有效解決所需大量繁雜迭代分析之問題，本研究特別運用工程應用程式整合技術，克服SAP2000軟體未提供使用者進行批次分析之限制，成功調控SAP2000達到以結構性能為目標的全橋耐震性能設計。
最後，本研究以中性化鋼筋混凝土橋梁為對象，逐年分析材料時變效應下之橋墩塑性鉸性質，並藉由非線性靜態側推分析與改良式容量震譜法，分別獲得橋梁結構容量曲線–時間與各種不同損壞等級對應之地表加速度–時間等之關係，進而建立橋梁易損性曲線之時變特性。據此，橋梁各種不同損壞程度之機率時變關係及其對應之耐震維修或補強等生命週期成本最佳化分析即可完成，所得成果可供為橋梁最佳化管理決策制定之參考。

關鍵字

遺傳演算法 ； 耐震性能設計 ； 生命週期成本

並列摘要

This paper, firstly, presents a fuzzy genetic optimization for performance-based seismic design (PBSD) of reinforced concrete (RC) bridge with single-column type piers. In the second place, a practical methodology are proposed to predict the life-cycle of the existing RC bridge and the crucial occasion to the necessary repairing or retrofitting for the neutralized bridges losing qualified performance.
To focus on the RC columns, fourteen results of cyclic loading test, three sets of experimental hysteresis loops and two varieties of pseudodynamic test were served as the materials for the necessary investigations on the performance-based seismic evaluation (PBSE). The results of the analysis show that the proposed approach would be well to predict nonlinear behaviors of RC columns and expected to facilitate the pushover analysis of the RC structure. After that, the PBSD method is modeled as a constrained optimization problem with the constraints of qualified structural capacity and suitable reinforcement arrangements for the designed RC pier. The structural capacity, represented by the structural force-displacement relation, obtained from the pushover analysis is required to satisfy the extreme case of multiple-level structural performances with respect to various earthquakes; the reinforcement arrangements is limited to the specification of the seismic design code. The fuzzy logic control (FLC), which adapts the penalty coefficients in the genetic algorithm (GA) as optimization solver, was employed to avoid a penalty that is too strong or too weak through the entire calculation so that a feasible solution can be obtained efficiently. The reported results of cyclic loading tests for three piers with squared section, rectangular section and circular section were employed as the data-base of investigation. Furthermore, a case study on the PBSD of a squared RC bridge pier with four required performance objectives (fully operational, operational, life safety and near collapse) was analyzed. Finally, the engineering application integration (EAI) technology was investigated to integrate with the proposed PBSD method and SAP2000 for accomplishing the purpose in PBSE of whole RC bridge system.
On the other hand, for existing reinforced concrete (RC) bridges, the structural performance is highly dependent on the changing properties of concrete and reinforcing steel due to neutralization-induced corrosion. To study the influence of neutralization on the existing RC bridges, the inspected data and test results collected from twenty-one bridges in Taiwan were examined to obtain the essential parameters through regression analyses. The regressive parameters related to service time can be employed in evaluating the variation of material and sectional properties in both reinforcements and concrete, and, accordingly, the change of structural performance from time to time could be obtained quantitatively via structural analysis. As a consequence, the performance degradation curve of an existing RC bridge is able to be predicted and, if necessary, the appropriate timing for repairing or retrofitting of it could be suggested.
This thesis combines GA with FLC to perform an optimization method for implementing the multiple performance objectives of RC columns in the PBSD. The relationships between structural performance and the service life are established successfully via a realistic procedure in evaluating the influence of concrete neutralization on RC concrete bridges in Taiwan. The results obtained could facilitate the PBSD of whole bridge system, analyzing the minimization of life-cycle cost for the neutralized RC bridges and enhance the functionality of bridge management system (BMS).

並列關鍵字

Genetic Algorithm ； Performance-Based Design ； Life-Cycle-Cost

參考文獻

[141] 宋裕祺，蔡益超，「以結構性能為目標的鋼筋混凝土橋耐震能力評估」，中華技術，2003，第58期。

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[148] 宋裕祺，葉祥海，蔡益超，謝尚賢，盧明德，蘇進國，賴明俊，「鋼筋混凝土牆、磚牆塑鉸設定與含牆建築物耐震能力評估之研究」，中華民國建築學會建築學報，第 62 期，2007，第81-98頁。

[166] 陳俊志，蘇進國，宋裕祺，黃震興，「鋼筋混凝土構架振動台試驗成果之分析與驗證」，中華民國第八屆結構工程研討會論文，南投日月潭，2006。

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