Dynamic characteristics of fiber reinforced rubber sand composite soil
In view of the shortcomings that the bearing capacity may decrease and the deformation is large when the granular mixture of rubber particles and soil is used as the foundation backfill material,this paper proposes to add polypropylene fiber to the composite soil for improvement.The effects of rubber content,fiber content and effective confining pressure on the dynamic shear modulus and damping ratio of the mixture were studied by resonance column test.The results show that with the increase of rubber content RC,fiber content FC and consolidation confining pressure σ3,the attenuation of dynamic shear modulus and the increase of damping ratio of composite soil are slowed down.The maximum dynamic shear modulus Gmax of composite soil is greatly affected by RC and σ3,and less affected by FC.And the empirical fitting formula of Gmax with RC,FC and σ3 are proposed.At the same time,this paper gives the recommended values of parameters A and B in the Davidenkov model of the G/Gmax~γ curve of the composite soil,and the linear growth formula of parameter γ0 and FC.The empirical formula proposed by Chen et al.is used to fit the damping ratio growth curve of composite soil,and the linear fitting formulas of λmin、λ0、β and FC under different test conditions are given.
fiber reinforced rubber sandshear strengthdynamic shear modulusdamping ratio