Deformation and shakedown analysis of river silt under long-term cyclic loads in Yellow River flooding area
With the aim of the national strategy of "YB Conservation and Development" and the rapid development of engineering construction along the Yellow River,the demand for filling soil materials increases dramatically,and the problem of shortage of construction resources is highlighted. As a new type of engineering filling material,the resource utilization prospects of Yellow River silt have been valued by relevant departments. To study the dynamic service characteristics of Yellow River silt under long-term cyclic loading,this paper selected typical samples and conducted large cycle (10000 cycles) triaxial tests under drainage condition based on GDS triaxial test system. Combined with shakedown theory,the influence of confining pressure,cyclic stress ratio,loading frequency,and density on the deformation characteristics of Yellow River silt was systematically analyzed. The long-term dynamic stability of the Yellow River silt was studied. The results are shown as follows. The cumulative strain and resilient strain increase with the increase of confining pressure,and decrease with the increase of frequency and density. When the cyclic stress ratio is low,the accumulation of strain quickly reached stability within a few hundred cycles at the initial loading stage. With the increase of cyclic stress ratio,the development of strain gradually exhibits creep properties and continues to accumulate after 5000 cycles. As the cyclic stress ratio continues to increase,the axial strain will rapidly increase in the early stage of loading,and the silt sample will reach failure state in a few cycles. By comparing with representative similar soil,it is found that the creep property of the Yellow River silt is between silty soil and sand. Based on the shakedown analysis of the Yellow River slit,an expression of allowable cyclic stress ratio of Yellow River silt is proposed,which can preliminarily judge the dynamic stability of Yellow River silt in the drainage state. The research results can provide parameter support for the further application and promotion of silty sand in practical engineering.
Yellow River siltdrained conditioncyclic loadingdeformation characteristicsshakedown theory
万方数据
维普
