裂隙砂岩冻融循环变形特征初探

采取汶马高速边坡砂岩预制裂隙后进行冻融循环试验;并进行冻融循环全过程裂隙的应变量监测,得到了在一次冻融过程中裂隙的应变过程经历了6个阶段,发现了岩样在冻融循环中的裂隙扩展由弹性变形转变为塑性变形,最终产生了残余应变。每一次初始的应变值即为上一次的残余应变值,而随着冻融循环次数的增多裂隙越来越大,呈对数增长的趋势。裂隙砂岩在冻融循环过程中,随温度变化,岩石的裂隙会产生新增或原裂隙扩展,宏观上表现为冻融损伤。

Preliminary study on the deformation characteristics of cracked sandstone under the freeze-thaw cycles

Taking the sandstone from slope of WEN-MA highway to do the freeze-thaw cycle test after prefabricated crack, with monitoring the strain value of cracks. The strain process of cracks during the freeze-thaw process is obtained, which is divided into 6 stages; The crack of rock propagation into plastic deformation by elastic deformation, finally produced residual strain in a . Every time the initial strain value is the last residual strain, and with the increase of the number of freeze-thaw cycles, the crack grows with a logarithmic trend. In the process of freeze-thawing, the cracks of rock with temperature changes can be added or expanded, and the macro performance is freeze- thaw damage.