挤压性地层中隧道围岩变形控制

Control of the cavity deformations in the squeezing rock

从穿越瑞士列奇堡隧道的挤压变形性极强的碳质页岩带的经验中,可以得出下述结论：圆形含承压单元的支护截面,其收敛变形性总趋势要比马蹄形不含承压单元的支护截面小；圆形支护截面与马蹄形支护截面的变形性没有本质的区别；由于山体构造的不均一性,导致开挖断面的不规则变形,这是使承压单元过早脱落的原因。

The experiences with the driving of the Letschberg - Basis tunnel through the carbonaceous shale can be summarized as follows： The convergences of the circular profile with yielding elements tend to be smaller than with the horse - shoe profile without such elements. The horse - shoe profile and the circular profile do not differ significantly in ductility. Irregular deformations of the mined cross section due to inhomogeneities of the rock mass led to the premature loss of yielding elements.