The Impact of Lift Joint on the Mechanical Properties of Cemented Sand and Gravel Material

Abstract

Cemented sand and gravel (CSG) material is a new kind of geotechnical material. Layered rolling technology is always adopted in the construction of CSG dam, which inevitably creates a weak layer between adjacent CSG material layers. This weak layer is called lift joint. In order to investigate the influence of lift joint on material properties, a discrete micromechanical model of CSG material with lift joint is established based on Lattice Discrete Particle Model (LDPM). Through the three-point bending tests, compression tests and triaxial tests, the parameters for this model are calibrated. Then the impact of lift joint on mechanical properties of CSG material, including compressive, tensile, and shear behavior is studied qualitatively from mesocopic view. The result shows that the weaker the lift joint is, the lower the material strength is, the more impact of the lift joint on the mechanical properties of CSG material is.