低温状态下冻土-浆脉结合界面的力学特性OA

Aiming at the problem of unclear mechanical properties of frozen soil-pulp vein interface failure in the construction of artificial freezing method in high water-rich strata,Brazilian splitting test combined with digital image correlation technology(DIC)was used to test the frozen soil-pulp vein combined specimens,and the effects of different initial water content and freezing negative temperature on the mechanical properties and fracture evolution mechanism of the interface were analyzed.The results show that the interface crack propagation modes of specimens with different initial water contents are significantly different and the initiation is non-synchronous.The decrease of initial water content makes the slurry vein effectively improve the strength of frozen soil,and the failure path changes from brittleness to toughness.The damage process of the specimens is divided into the accumulation stage and the rapid stage.When the initial water content increases,the duration of the damage accumulation stage and the size and occurrence time of the damage acceleration point Df increase first and then decrease.The research conclusions provide technical support for the application of freezing method in underground engineering.