内河疏浚土抗剪强度随含水率变化规律的试验研究

Experimental study on variation law of shear strength of river dredged silt with water content

疏浚土的综合利用在促进社会和谐发展、建设节约型资源、发展低碳经济方面具有举足轻重的作用。采用大变形多功能土工环剪仪,对京杭运河施桥船闸段疏浚淤泥土的物理力学特性进行试验分析,研究约束压应力对固化土强度的影响。结果表明,内河淤泥试样的密度、孔隙比、液限、塑限、液性指数、塑性指数等物理参数随着淤泥含水率的增加而降低;生石灰固化剂的添加能够明显改良淤泥土的物理参数;淤泥固化土料的压缩模量、黏聚力、内摩擦角受到轴向约束压应力的显著影响。实际工程中建议增大固化土料的轴向压缩应力以提高土料强度。

The utilization of dredged soil plays an important role in promoting the harmonious development of society,building energy-saving resources and developing low-carbon economy.The properties of dredged silt in Shiqiao Lock section of the Beijing-HangzhoUGrand Canal are tested and analyzed by large deformation multi-functional geotechnical ring shear instrument,and the influence of restrained axial compressive stress on the strength of curing soil is studied.The test results show that the physical parameters such as bulk density,void ratio,liquid limit,plastic limit,liquid indeXand plastic indeXof river silt samples decrease with the increase of silt s water content.The addition of curing agent can obviously improve the physical parameters of silt soil.The compression modulus,cohesion and internal friction angle of curing silt are significantly affected by the axial confined compressive stress.In practical engineering,it is suggested to increase the axial compressive stress of curing soil to further improve the strength of soil.