玄武岩纤维土工格栅加筋膨胀土三轴试验  

Triaxial tests of expansive soil reinforced with basalt fiber geogrid

作　　者：周健[1,2] 徐洪钟[1] 

机构地区：[1]南京工业大学交通学院,江苏南京210009 [2]常州市中元建设工程勘察院有限公司,江苏常州213001

出　　处：《南京工业大学学报（自然科学版）》2013年第5期105-109,共5页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金(41072217)

摘　　要：采用玄武岩纤维双向土工格栅加筋膨胀土,分层压实成直径101 mm、高200 mm的试样,进行加筋与不加筋、饱和与非饱和的膨胀土试样在不同围压下的固结不排水三轴试验,研究其强度特性的变化。结果表明:饱和试样破坏模式表现为塑性破坏,非饱和试样破坏模式表现为偏脆性破坏;非饱和试样达到峰值强度时的轴向应变(5%以内)明显小于饱和试样(11%左右),同时峰值强度显著增加;同种加筋类型下,非饱和试样黏聚力远远大于饱和试样,而内摩擦角提高相对较小;无论饱和试样还是非饱和试样,与未加筋土相比,加筋膨胀土初始屈服应力增大,峰值强度提高,且随加筋层数增多,其提高值增大;无论饱和试样还是非饱和试样,加筋使膨胀土的内摩擦角略有提高,而黏聚力提高值相对明显。The expansive soil samples reinforced with basalt fiber geogrid with the size of φ101 mm×200 mm were adopted to carry out a series of CU triaxial tests for reinforced and unreinforced, saturated and unsaturated soil samples under different confining pressures. The strength characteristics of reinforced expansive soil samples were researched. The results showed that the failure mode of saturated soils was the plastic damage and that of unsaturated soil samples was partial brittle failure. The axial strain （less than 5 % ） of the unsaturated soil sample on peak strength was obviously less than the strain （ about 11% ） of saturated soils, and there was a significant increase in the peak intensity. With the same types of reinforce- ment, the cohesion of the unsaturated soil was far greater than that of the saturated soil, and the internal friction angle improvement was relatively small. No matter saturated or not saturated, compared with the unreinforced expansive soil, the initial yield stress and the peak strength increased, and the increment was more evident with more layers of geogrid. No matter saturated or not saturated, the internal friction angle of the reinforced expansive soil was only improved a little, but the cohesion was obvious increased.

关 键 词：玄武岩纤维土工格栅 膨胀土 三轴试验 应力应变特征 

分 类 号：TU443[建筑科学—岩土工程]