The invention belongs to the technical field of underground
engineering materials and particularly relates to concrete for high-ground stress and high-
ground temperature tunnel excavation primary support. 1m<3> of concrete comprises the following raw materials in
mass: 350 to 400kg of
cement, 850 to 1,000kg of coarse aggregate, 450 to 550kg of sand, 200 to 220kg of water, 50 to 100kg of II-grade
fly ash, 20 to 40kg of
basalt fiber, 10 to 15kg of redispersible latex
powder, 6 to 8kg of steel-imitating
fiber, 2 to 3 kg of high-performance poly-
carboxylic acid water
reducing agent and 10 to 15kg of accelerated agent. The concrete has
heat tolerance and the function of preventing the brittle failure, such as
rock burst; comprehensive problems of
rock burst and terrestrial heat damage can be solved; the concrete is easy to stir and mix and good in construction performance; after being ejected onto a
wall rock, the concrete can be quickly
felted with the
wall rock; under the action of the accelerated agent, the concrete is hardened with relatively short time. After the concrete is hardened, the concrete is good in
heat tolerance, high in compression strength, high in tensile strength, high in bending strength, good in
toughness and good in
crack resistance.