一、前言 在我国铁路隧道、矿山井巷以及地下工程中,已大量采用喷射混凝土新技术。喷射混凝土与传统支护方法比较,可以节省模板和支撑材料,改善劳动条件,减薄衬砌厚度,从而加速施工进度,降低工程造价。 目前喷射混凝土材料多采用硅酸盐水泥为胶结材料,掺加粉状速凝剂,干法施喷。其主 I. Preface In China’s railway tunnels, mine shafts and underground works, a large number of new technologies have been adopted for shotcrete. Compared with traditional support methods, sprayed concrete can save formwork and supporting materials, improve working conditions, and reduce the thickness of linings, thereby accelerating construction progress and reducing project cost. At present, Portland cement is mostly used as cementing material for sprayed concrete materials, mixed with powdered accelerator, and sprayed dry. Its owner