基于应变软化模型的隧道洞群施工步序优化

Optimization of construction sequence of tunnel group based on strain softening model

夹层围岩受到隧道洞群各洞室施工的多次扰动,其强度不断降低。FLAC3D应变软化模型能有效模拟施工扰动而导致的围岩力学参数降低的过程。文章基于摩尔-库仑准则,提出围岩安全度概念,定量评价夹层围岩受力状态;综合考虑夹层围岩安全度及各洞室变形,定量评价洞群各施工步序的优劣,得出最优施工步序。

The interlayer surrounding rock is disturbed many times by the construction of every chamber in the tunnel group, and its strength decreases continuously. FLAC3D strain softening model effectively simulates the reduction of mechanical parameters of surrounding rock caused by construction disturbance. Based on the M-C Law, the concept of surrounding rock safety is proposed, and the mechanical state of interlayer surrounding rock is evaluated quantitatively. Considering the safety degree of the surrounding rock and the deformation of each chamber, it quantitatively evaluates the advantages and disadvantages of all construction sequences of the tunnel group, and obtains the optimal construction sequence.