地下洞室群开挖顺序优化设计

遵循动态规划原理建立了地下洞室群开挖顺序动态规划模型,提出了评价不同开挖排序方案优劣的最小能量偏差准则,并以能量偏差为目标函数.实例计算表明,开挖顺序对围岩稳定的影响是明显的,对开挖顺序的优化要给予重视;提出的地下洞室群开挖顺序动态规划模型合理,计算工作量较少;以形状改变比能偏差为目标函数的优化方案中最大洞周位移比位移类目标函数的最大洞周位移略大,但从应力状态、塑性区面积和能量的角度考虑,前者的优化方案更佳.因此,以形状改变比能偏差为目标函数更合理.

Optimum design of excavation sequence underground cavity groups

Based on the dynamic programming principles,a dynamic programming model of excavation sequence for underground cavity groups was presented.The minimum strain energy deviation(objective function) criteria were proposed to choose the optimum scheme of the excavation sequence.The case studies show that the effect of excavation sequence on the stability of the surrounding rocks is obvious,and much attention should be paid to the optimum design of the excavation sequence.The present model is reasonable and easy to calculate.The maximum displacement around the cavity calculated by the deviation of shape change specific energy as the objective function is a little larger than that by the displacement as the objective function,but from the viewpoint of the stress conditions,the area and energy of plastic zones,the former is much better.Therefore,it's more reasonable to use the deviation of shape change specific energy as the objective function.