Relationship between small-strain shear modulus and growth of strength for stabilized silt

The small-strain shear modulus and unconfined compressive strength are two important parameters to characterize the stiffness and strength of stabilized soils. The fundamental and the main problems existing in the experiment of bender element technique are briefly reviewed. The small-strain shear modulus of cement and lignin stabilized silt are tested under different curing time by piezoelectric bender element technique. The conventional unconfined compressive strength test is also carried out on stabilized samples under different curing time. The relationships between the small-strain shear modulus and unconfined compressive strength of different stabilized soils are analyzed by introducing the normalized parameters G28 and UCS28. A stabilization model for the stiffness and strength of stabilized soils is proposed to provide a new method for the non-destructive testing and evaluation of stabilized soils in ground improvement. It is found that the small-strain shear modulus of the stabilized silt increases with the increase of curing time. The small-strain shear modulus of the stabilized silt increases dramatically during 28 d curing time and gets steady after 28 d. The results suggest that for a given binder, the small-strain shear modulus development with time is essentially the same regardless of the dosage. The normalized unconfined compressive strength of stabilized silt shows similar characteristics to the normalized small-strain shear modulus. The proposed normalized model for stabilized soils can be used as a new method for non-destructive prediction of soil strength. © 2015, Chinese Society of Civil Engineering. All right reserved.