Study on Macro Mechanical Parameters of Solution Pore and Crevice Limestone Rock Mass

The limestone stratum has better reliability and suitability, which has certain guiding significances to the engineering construction of similar fields. Limestone stratum has great anisotropy and large karst caves, pipelines, faults to small dissolution cracks and voids are distributed in limestone. The anisotropy is relatively maturing in engineering exploration and treatment. The mechanical parameters, namely solution pore & crevice limestone were studied, and the following conclusions were drawn. There is a good power function relationship between compressive strength and porosity of solution pore and crevice limestone. The power constant is close to-0.5, the formula is y=ax^-0.5, and its coefficient represents the compressive strength of rock with 1% porosity. Based on Hoek-Brown strength criterion and rock mass porosity n, the relationship between rock mass parameters m_b, S, a and porosity n is established, and rock mass mechanical parameters (compressive strength R_cm, tensile strength R_tm, shear strength parameters c_m and φ_m of rock mass) are described by porosity. It simplifies the complexity of mechanical parameters selection by quantifying GSI, and avoids subjectivity and uncertainty of quantifying GSI, and it has good reliability and suitability in pore and crevice limestone stratum. The study has certain guiding significance for the construction of similar sites.