土岩接触复杂地层中接触面力学性质研究

Study on mechanical behavior of interface between soil and rock in complex strata

为了探讨在土、岩地层中隧道工程施工引起的塌方问题,以宝天高速公路隧道工程为例,通过室内常规土的物理力学性质指标测试,土、岩接触面直剪试验,研究了土、岩接触地层中接触面的力学性质,得到不同含水率、不同固结压力下土、岩接触面的抗剪强度参数。研究表明:①土、岩接触面中岩侧具有一定阻渗作用;②随着含水率的增大,土、岩接触面的粘聚强度减小,而摩擦强度变化较小。

In order to discuss the collapse problem in tunnels on soil-rock interface,taking Baoji-Tianshui highway tunnel project as an example,we studied the physical mechanical property of soil-rock interface,and obtained the shear strength parameters of soil-rock interface stratum under different water contents and consolidation pressures through conventional laboratory test of soil physical mechanical property indexes and direct shear test of soil-rock interface.The research shows that：① soil-rock interface can prevent seepage to some extent;② with the increase of water content,the cohesion strength of soil-rock interface decreases,and the frictional strength changes a little.