干湿循环对板岩填料抗剪强度劣化影响的试验研究  

Experimental study on the deterioration of shear strength of slate filling under dry-wet cycles

作　　者：陈兴[1] 张静波[1] 吕岩松 杨露 江洎洧[3] 

机构地区：[1]中交第二公路勘察设计研究院有限公司,武汉430056 [2]贵州高速公路集团有限公司,贵阳550004 [3]长江科学院水利部岩土力学与工程重点实验室,武汉430010

出　　处：《工程勘察》2017年第7期5-9,共5页Geotechnical Investigation & Surveying

基　　金：贵州省交通运输厅科技项目(2014-122-007)

摘　　要：针对贵州省三黎高速公路强—中风化板溪群板岩填料,开展了不同干湿循环次数条件下的大型三轴压缩试验。试验结果表明:干湿循环效应对于板岩填料的抗剪强度参数影响是较为显著的,特别是首次干湿循环后,抗剪强度参数有明显的变化,而当干湿循环次数进一步增加时,强度仍有变化,但较第一次弱;板岩填料的黏聚力c值随干湿循环次数增多近似呈线性增长,内摩擦角φ值随干湿循环次数增多近似呈幂函数减小;首次干湿循环后,内摩擦角φ值下降约7%,黏聚力上升约26%,但总体抗剪强度仅有约2%~7%的下降,说明干湿循环效应对强—中风化板溪群板岩路堤边坡稳定性影响不大。另外,本文对板岩路堤填料的干湿循环大型三轴压缩试验条件和方法进行了探讨,可为同行提供参考。In order to study the evolution law of the shear strength of slate embankment fillings under the climate environment, large scale three axial compression tests were carried out under different cycles of wetting-drying in the filling material of middle decomposed Banxi formation slate in Sansui-Liping Expressway, Guizhou Province. Experimental results show that the dry-wet cycle effect on the shear strength of the filler effect is great. The shear strength is obviously weakened for the first dry-wet cycle ; while with the cycle number increases, the strength is deteriorated, but the change is weaker than the first Cycle; the cohesive value c of slate increases linearly and the friction angle value tp is approximately power function decreasing with the increase of dry-wet cycles. For the middle decomposed slate filling of Banxi formation in Sansui-Liping Expressway, after the first dry-wet cycle, the internal friction angle decreases 7%, cohesion increases about 26% , but the overall shear strength is declined only about 2% -7%. That is to say, the wet-dry cycles has little effect on the stability of embankment slope filled with middle decomposed Banxi formation slate. In addition, the conditions and method of triaxial compression test with the wet-dry cycles of slate fillings is discussed in the paper which could be referred by the similar projects.

关 键 词：板岩 路堤 干湿循环 三轴压缩试验 

分 类 号：TU411[建筑科学—岩土工程]