层次分析法在隧道断面多目标优化中的应用

Multi-objective Optimization in Tunnel Section Based on Analytic Hierarchy Process

利用有限差分软件对不同矢跨比的隧道开挖后的应力分布、应力集中、洞周位移、拱顶下沉和塑性区面积进行数值模拟分析。运用层次分析法,对影响隧道断面的各因素进行分析和调整,建立层次关系,构造阶层结构,给出层次分析法的算法流程,应用于四个不同矢跨比的隧道断面,以开挖面积、洞周水平收敛位移、拱顶下沉位移量、开挖后围岩塑性区面积和应力集中系数为指标,在满足隧道建筑限界的前提下,选择最优断面形状。

Based on finite difference method, numerical analysis about tunnels with different rise - span was carried out from five aspects as followings： stress distribution, stress concentration, convergence of tunnel inner perimeter, vault settlement and distribution of plastic zone in surrounding rock. Using the analytic hierarchy process, hierarchical relations among the factors influencing tunnel cross and the hierarchical structure were built. Finally, the arithmetic flow of the method was put forward, and the proposed method was applied to 4 tunnels with fixed span but different sections. Through the analysis results, an optimal cross section satisfying tunnel construction clearance was detennined by the method with the five factors mentioned above.