Liquefaction Characteristics Of Recycled Concrete Aggregates

In recent years,China's urbanization has advanced by leaps and bounds.But at the same time,the disposal of the construction waste aggregate brought with the rapid development of construction has become a big problem.The main treatment method of construction waste aggregates is landfill utilization.In case of the increase diversity and complexity of seismic loads,a large amount of construction waste widely used for reclamation may lead to a failure phenomenon similar to the liquefaction of quartz sand(and other granular materials)under earthquake action.However,a large number of scholars' research on construction waste mainly focuses on the influence of physical properties and shear strength.Therefore,this paper has carried out a series of laboratory tests,which mainly include the following:1.The physical and chemical characteristics of recycled concrete aggregate are introduced,and the reasons for the differences are analyzed,which provide a basis for the study of dynamic characteristics.2.The drainage test of Fujian standard sand and recycled concrete aggregate has been carried out with resonance column.The effects of differentconfining pressures on shear modulus and damping ratio are discussed separately.3.With the recycled concrete aggregate and the standard sand being in the same grading curve,a series of undrained tests were carried out under different relative compactness,density,different confining pressure,cyclic stress ratio and B value.At the same time,the microscopic mechanism of the test results was explained.4.Construction waste consists of broken concrete granules,cement,etc.,and is shaped like an angular shape.The recycled concrete component material has poor tensile properties,so its particles are considered to be broken.The gradation of the samples was tested and the crushing condition was checked after sample preparation,consolidation,and initial liquefaction under the un-drained test conditions.The non-uniform coefficient of gradation and surface area were used for quantitative analysis of particle breakage.