Experimental Studies On Dynamic And Strength Characteristics Of Marine Soft Soil In The Beibu Bay

The blast-filled ground is often filled with a large area and deep soft soils of sedimentary facies,which is likely to amplify the seismic wave in the event of an earthquake,and which contribute to the damage of buildings in the blast-filled ground.So research on the dynamic response of marine soft soils in the blast-filled ground is very necessary.As a factor affecting dynamic and strength characteristics of marine soft soils,analyze the concrete influence of water content,consolidation degree and confining pressure on the dynamic characteristics of marine soft soil is the main problem of this paper.In this paper,a large number of dynamic tests were carried out on the soft soil of the underground of Fangchenggang enterprise sand industrial park by the GDS dynamic three axis instrument.The effects of different water content,consolidation degree and confining pressure on the dynamic and strength characteristics of marine soft soil are studied,which applies experiment and data support to the seismic design and vibration reduction of the blast-filled ground.The main research contents on the marine soft soil include the basic physical and mechanical parameters test,soil dynamic deformation test under different factors of marine soft,the dynamic strength test under different factors.Main conclusions and innovation point of this paper are as follows:1.Different dynamic strains have different dynamic stresses With the increase of amplitudes of dynamic stresses,dynamic strains transform from steady states to extended states.Confining pressure,moisture content and consolidation degree have great influence on the development of hysteresis curves and backbone curves,dynamic elastic modulus and damping ratios of marine soft soils.And according to the existing test data,the curve of each backbone curve is fitted by the Hardin-Drnevich hyperbolic model.The maximum damping ratio and maximum dynamic elastic modulus are calculated,and the dynamic elastic modulus attenuation model is also established.2.The failure criterion of the specimen was determined by the axial strain of 10%.The confining pressure and the water content have great influence on the dynamic strength of marine soft soils.With the increase of confining pressure,the larger the dynamic strength,and the larger the water content,the smaller the dynamic strength.The dynamic strength indexes,cd and φd,of different water content and failure vibration were calculated,And the former decreases with the increase of the latter.