Study On Rheological Properties Of Mucky Soil And Its Engineering Application

With the constant development of China's economy,the demand for the construction of various infrastructures continues to increase.However,most developed cities are in soft soil district where in coastal and Yangtze river area.And most of the rail transit,airport,piers and seawall projects constructed in thse areas are on soft ground.Various engineering problems due to the characteristics of soft soil have also come along with it.,in which the soil settlement caused by the settlement and uneven settlement is particularly significant.In this paper,the mucky soil from Yijiang district,Wuhu,Anhui will be the research object,followed by analyzing and researching the loss of mucky soil based on the project characteristic of mucky soil in Yijiang district.The main steps showed as below,1.The indoor experiment of mucky soil's basic physical and mechanical properties.This test select three typical fault surfaces,9 holes,about 150 soil samples and tests moisture content,particle analysis,dry density,consolidation,compaction,direct shear,triaxial compression and other indoor experiments,the physical and mechanical property targets of the soft oil in above district can be obtained.The results shows that the mucky soil in selected district is a typical soft plastic clay with engineering characteristics of high compressibility,low strength and low permeability.2.Triaxial rheological tests on mucky soil.In this paper,the triaxial compression tests under different confining pressures are able to obtain yield strength of mucky soil,and then,according to the yield strength,proceeding three-axis rheological test under different stress levels.Moreover,studying and analyzing the creep deformation of mucky soil under different stress levels and get the relationship between stress of mucky soil,strain and time.3.Analyzing the relationship between stress of mucky soil,strain and time in this area.On the basis of Singh-Mitchell model and Mesri model,the creep equation corresponding to the rheological properties of mucky soil is established,and the fitting results of this model will be compared with the test curve.According to the time hardening method in the Drucker-Prager model of ABAQUS,the rheological constitutive model of mucky soil of Qingyijiang engineer in Wuhu Anhui was established,and the creep parameters A,m and n are calculated.4.Numerical simulation analysis.Using finite element analysis software ABAQUS,the model of dam settlement considering rheology was established,the settlement value of dam was calculated and compared with the settlement value without considering the rheology.It was found that the influence of rheology on post-construction settlement can not be neglected.Moreover,on the basis of this model,the sensitivity of the model parameters is analyzed.The effects of creep parameters A,m,n,Young's modulus E,Poisson's ratio ?,cohesion c,and friction angle ? on settlement are studied respectively.