Study On Mechanical Response Of Simulated Structure Of Rubber Sand Mixed Soil Subgrade

Subgrade is the foundation of road structure,its performance directly affects the overall stability of the road,and the main factor determining the quality of subgrade is the selection of subgrade filler.As a new filling material,rubber sand mixed soil can improve the mechanical properties of Aeolian Sand Roadbed on the one hand,and solve the recycling problem of waste tires on the other hand.In addition,rubber sand is a composite soil composed of rubber particles and aeolian sand,its mechanical properties are different from that of traditional pure sand,and its mechanical performance is determined by both sand and rubber.The performance of rubber sand mixed soil needs to be measured in practical application,but there are some differences between the indoor conventional forming method and the actual construction stress forming method,which will lead to the deviation of the indoor test results when they are directly applied to the actual situation.Therefore,the indoor test results need to be modified to get close to the actual situation.Therefore,based on the indoor conventional test,this paper passes the subgrade simulation structure test Through comparative analysis,we can get the connection and difference between indoor routine test and practice.1.Through the particle screening test and heavy compaction test of the rubber sand mixed soil,the basic properties of the two are determined.The results show that the aeolian sand and the rubber sand mixed soil belong to the poor gradation,and the mixed soil belongs to the discontinuous gradation.It is concluded that the higher the quality of the rubber particles is lower than 2mm,the more likely to lead to the irregular change of the water content relationship curve,and the rubber content and the dry density of the mixed soil are obtained Empirical formula for the value.2.The results show that the shear displacement and shear stress of rubber sand are strain hardening type,and the pure sand is strain soft type.The shear strength of aeolian sand,rubber particles and mixed soil can be improved by adding rubber particles into aeolian sand to a certain extent;the cohesive force of mixed soil increases with the addition of rubber particles When the internal friction angle is only considered,30%of No.1 rubber content is the best particle size and content;the bearing ratio of mixed soil decreases with the increase of content,but compared with pure sand,the bearing capacity of mixed soil has certain advantages under high pressure,and the rubber content of 0%?40%can meet the requirements of construction specifications.3.Through the indoor simulation structure of different kinds of rubber sand mixed soil with different content by vibration compaction and the relevant tests by coring,the results show that the direct shear and CBR test results of the mixed soil under vibration compaction are higher than the compaction results,and there is a certain linear relationship between the two different molding methods in numerical value.At the same time,the five kinds of CBR content under vibration compaction are all It can meet the requirements of construction specifications,and the layered paving of rubber sand can improve a certain degree of compaction.