Experimental Study On Mechanical And Microscopic Properties Of Residual Soil In Wenzhou

In addition to the soft clay of large area,there are also widely distributed residual soil areas in Wenzhou area,which are mainly concentrated in Cangnan and Taishun areas in the south of Wenzhou.With the increase of engineering construction of residual soil areas,engineering accidents caused by the unique mechanical properties of residual soil have become common.The mechanical properties of residual soil are also caused by serious natural disasters,such as climate environment,parent rock type,mineral composition content,regional landslide,collapse and so on.Therefore,the influence of Wenzhou weathering degree is slightly different,so it can be regarded as a kind of regional special soil.However,at present,there are few studies on the mechanical properties of residual soil in Wenzhou area and the mechanical properties of residual soil in Wenzhou are also of great significance because of its high mechanical strength and fast softening in the event of water.In this paper,the mechanical properties and microstructure of Wenzhou residual soil are studied by means of field exploration,in situ sampling and some indoor tests,taking the residual soil produced in the process of excavation of a deep foundation pit in Matan Town,Cangnan County,Wenzhou City as the research object and the residual soil obtained at different depths in the space.The meaningful conclusion research contents of this paper are as follows:(1)Present situation of residual soil research at home and abroad is summarized and the research direction of mechanics and microscopic characteristics of Wenzhou residual soil is clarified.Through a series of laboratory tests,including soil sample test,limit moisture content test,compaction test and XRD analysis test,the physical properties and chemical composition of Wenzhou residual soil are obtained.(2)The saturated salt solution steam balance method was used to control the suction in the remolded Wenzhou residual soil with different initial dry densities.The mechanical strength characteristics of the remolded Wenzhou residual soil samples and the undisturbed residual soil samples from different depths were studied under different suction conditions.The soil water characteristic curves of the remolded Wenzhou residual soil and the shear strength index of Wenzhou residual soil under different depth and different suction conditions were obtained.To evaluate the engineering mechanical properties of Wenzhou residual soil.(3)The microstructure of Wenzhou residual soil was studied by mercury injection test and scanning electron microscope test.The pore structure and composition of Wenzhou residual soil were analyzed,which provided support for the conclusion of macromechanics.