Research Article

Behaviors and Overlying Strata Failure Law for Underground Filling of a Gently Inclined Medium-Thick Phosphate Deposit

Table 3

The physical and mechanical properties of the rock.

Geotechnical typeUniaxial compressive strength (MPa)Uniaxial tensile strength (MPa)Cohesion (MPa)Internal friction angle (°)Poisson’s ratioDensity (kg/m3)

Topsoil13.320.130.9540.000.111800
Layered cryptocrystalline dolomite18.171.045.0042.500.382580
Medium to coarse crystalline dolomite28.202.267.2444.200.302610
Layered argillaceous dolomite28.023.135.7644.200.252580
Pebbly quartz sandstone52.992.203.1043.680.272620
Industrial phosphate rock82.276.6710.7843.400.202660
Low-grade phosphate rock70.804.389.4443.600.202566
Off-white medium-layered dolomite50.503.079.0660.000.332500
Primary medium-thick layered dolomite59.103.299.0741.260.232624

Engineering analog data.