关键词: 井筒施工, 高强低热混凝土, 冲积层, 冻结段

Abstract: Application of C40~C80 high strength concrete with low freezing section in zhaogu second mine shaft as the background. The alluvium thickness is 530.5m, the freezing depth 615m, using double layer reinforced concrete plastic sandwich wall structure. The use of cement, sand, gravel, fly ash, slag and chemical admixtures according to different ratio, low heat of hydration with different strength and early strength crack compacting high performance concrete,the actual strength of more than 5% of the design intensity, which improves the strength reserve of the shaft wall, effectively prevents the destruction of the wall. Hydration heat reduces 15~17 degree C, better control the inner and outer wall mass concrete temperature crack expansion, to ensure the construction safety of the frozen section.