Experimental Study On Small Strain Dynamic Characteristics Of Steel Slag Stabilized Silty Clay

Soft silty clay foundation is widely distributed in the eastern coastal areas of China.With the continuous construction of buildings and infrastructure in these areas,seismic,traffic and other dynamic loads will seriously affect the stability and bearing capacity of the foundation.Therefore,the reinforcement of silty clay foundation has become a common concern.In this paper,scrap steel slag is used to improve the dynamic characteristics of silty clay foundation.By analyzing the mineral composition,physical and chemical properties,cementing properties and hydration mechanism of steel slag,the effect of steel slag in the treatment of silty clay foundation is explored.In this paper,the influence of different confining pressure,curing age and mix proportion on dynamic shear modulus and damping ratio of steel slag silty clay mixture is studied by resonance column test,and compared with cement silty clay mixture,which provides theoretical basis for steel slag to replace cement in silty clay foundation treatment.The results show that with the increase of confining pressure,the dynamic shear modulus increases and the damping ratio decreases.With the increase of curing age,the dynamic shear modulus increases and the damping ratio decreases,but the effect of curing age on the damping ratio is relatively small.The mix proportion has a significant effect on the dynamic shear modulus and damping ratio of steel slag silty clay mixture and cement silty clay mixture.With the increase of steel slag content,the dynamic shear modulus and damping ratio of steel slag silty clay mixture increase first and then decrease.When the steel slag content is 30%,the dynamic shear modulus and damping ratio reach the maximum at the same time;With the increase of cement content,the dynamic shear modulus and damping ratio of cement silty clay mixture increase gradually,and reach the maximum when the cement content is 15%.When the content of steel slag is 30%,the maximum dynamic shear modulus and the maximum damping ratio of the steel slag silty clay mixture are close to those of the cement silty clay mixture with 15%cement content,and with the increase of curing age,the maximum dynamic shear modulus and the maximum damping ratio of cement silty clay mixture are gradually smaller than those of steel slag silty clay mixture.The test results show that 30%steel slag can be used to replace 15%or less cement in silty clay foundation,which not only improves the dynamic characteristics of the foundation,but also improves the utilization rate of steel slag.