Dynamic Shear Characteristics of Residual Soil-geotextile Interface Under Different Water Contents
The subgrade slope of granite residual soil is prone to instability under the action of rainfall and dynamic load.The reinforced-soil technology can effectively enhance the strength and stability of the subgrade.To reflect the interfacial dynamic shear characteristics of the subgrade slope of geotextile reinforced granite residual soil under the influence of water contents and dynamic load,a large indoor direct shear instrument was used.The effects of water contents(12％,16％,20％,24％),vertical stresses(50 kPa,100 kPa,150 kPa,200 kPa)and shear amplitudes(1 mm,3 mm,6 mm,9 mm)on dynamic shear characteristics of the interface of granite residual soil-geotextile interface were investigated using horizontal cyclic direct shear tests.The changing rules of interfacial shear stress,vertical deformation,and shear modulus under the action of the three factors were analyzed.Regression analysis was applied to the shear stress rule of the interface of reinforced soil.Results showed that the interface of reinforced soil had a tendency of shear softening under high water content(20％,24％)and large shear amplitude(6 mm,9 mm)during cyclic shear.Under different vertical stresses,the interface of reinforced soil with 12％water content showed shear hardening,while the interface with 24％water content showed shear softening.The increase in vertical stress reduced the shear softening trend of the interface with increasing water content.The vertical deformation was the smallest when the water content was 16％.The interfacial shear stiffness decreased with the increase of water content and shear amplitude,and the decrease in amplitude increased under cyclic shear.Based on the Kondner hyperbola,the expression of hysteresis loop related to water content was established using the modified Masing curve method.The calculated hysteresis loop curves was consistent with the experimental results.
subgrade engineeringreinforced soilcyclic direct shear testgranite residual soilgeotextilewater content
NETL
NSTL
万方数据
