67 Failure Criterion of Rock-Soil-Concrete and Estimate of Its Strength Parameters

Failure criterion of rock-soil-concrete presented briefly in this paper. Making an estimate of strength parameters of rock, soil and pile is very necessary in numerical simulation and stability calculation of pile foundation, excavation pit and slope with the retaining structure. The formulae of calculating cohesion and internal friction angle of rock, soil and the retaining structure(pile) are derived from four combination conditions of two-dimensional and three-dimensional stresses with failure criterions Mohr-Coulomb's inclined line and Mohr's parabola, finally deviation is discussed. The study results have the important theoretical significance and practical value of engineering.