双连拱隧道内轮廓优化设计模型及其应用

从双连拱隧道结构设计的全局出发，提出了3种双连拱隧道单洞常用内轮廓形状（单心圆、坦三心圆及尖三心圆）的优化选型计算方法，建立了以路面以上开挖面积最小为目标函数，以满足限界、通风、受力等要求为约束条件的优化模型，并采用简易复形法对其进行了求解。运用建立的优化模型及编制的计算机程序对某工程实例进行了计算比较，结果合理，表明其可行性及有效性。

Optimum Design Model of Inner Outline of Double Multi-arch Tunnel and Its Application

Considering the overall situation of the design of double multi arch tunnel, the optimum mod el of the single hole of double multi arch tunnel is presented for three kinds of commonly used inner outline shapes, that is, single center circle, three center tabular circle and three center sharp circle. To satisfy the requirements of structural approach limit, ventilation and mechanical force, which are restrictive conditions of the model, a function aiming at minimizing excavation area over the pavement is put forward. And simple Plu ral method is adopted to solve this model, for which the calculating program is developed. Applying the opti mum model and the program developed to calculate the practical engineering, the results indicate that they are feasible and efficient. Moreover, they can be used in similar structure design of double multi arch tunnels.