地面以下存在着各种地下水，如上层滞水、潜水、承压水、裂隙水、岩溶水等。 上层滞水存在于地表岩层，以分子水、结合水和毛细管水等形态出现，也有下渗水流的存在；潜水存在地表层以下、第一层稳定的不透水层以上，一般以自由水的形态存在；承压水处于两层不透水层之间，以有压水的形态存在；裂隙水可以是结合水或毛细水，也可以是自由水或承压水；岩溶水含水量大，一旦透水会突然大量涌出。 地下防水工程的要求防水等级划分： 一级：不允许灌水，围护结构无湿渍； 二级：不允许漏水，围护结构有少量、偶见的湿渍； 三级：有少量漏水点，不得有线流和流泥砂，每昼夜漏水量小于0.5L/m2； 四级：有漏水点，不得有线流和流泥砂，每昼夜漏水假山制作 不锈钢铸件 铝箔真空袋 七孔梅花管 hdpe硅芯管 液压钢坝 PVC软管 飞行激光打标机 沥青保温泵量小于2L/m2. 地下工程的防水，应遵循“防、排、截、堵相结合，因地制宜，综合治理”的原则。 地下工程的防水，应考虑地表水、潜水、上层滞水、毛细管水等的作用，以及人为因素引起的附近水文地质改变的影响。在设计时应优先考虑自流排水和防水混凝土自防水结构，选定方案应注意以下条件： （1）对受振动的工程，应采用柔性防水卷材或涂料等防水方案。 （2）对处于冻土层中的工程，当采用混凝土结构时，其混凝土抗冻融循环不得小于100次。 （3）具有自流排水条件的工程，应设自流水排水系统。无自流排水条件，有渗漏水或需应急排水的工程，应设机械排水系统。
There are various kinds of groundwater below the ground, such as perched water, phreatic water, confined water, fissure water, karst water, etc. The upper stagnant water exists in the surface rock stratum, in the form of molecular water, combined water and capillary water, and also in the form of infiltration water; the phreatic water exists below the surface layer and above the first stable impermeable layer, generally in the form of free water; the confined water exists between the two impermeable layers, in the form of pressurized water; the fissure water can be combined water or capillary water, or it can be So it is free water or confined water; karst water has a large water content, and it will suddenly gush out in large quantities once it is permeable. The requirements of underground waterproof engineering are divided into the following levels: first level: no irrigation is allowed, and the enclosure structure is free of moisture; second level: no water leakage is allowed, and the enclosure structure has a small amount of occasional moisture; third level: there are a small amount of water leakage points, no wire flow and quicksand, and the water leakage per day and night is less than 0.5l/m2; Class IV: there are water leakage points, no wire flow or quicksand is allowed, and the water leakage per day and night is less than 2L / m2. The waterproofing of underground works shall follow the principle of "combining prevention, drainage, interception and blocking, adjusting measures to local conditions, and comprehensive treatment". For the waterproofing of underground works, the functions of surface water, phreatic water, upper stagnant water, capillary water, etc., as well as the influence of the hydrogeological change caused by human factors shall be considered. In the design, the self drainage and waterproof concrete self waterproof structure should be given priority, and the following conditions should be paid attention to in the selected scheme: (1) for the project subject to vibration, the flexible waterproof roll or coating and other waterproof schemes should be adopted. (2) For the project in the frozen soil layer, when the concrete structure is adopted, the concrete freeze-thaw resistance cycle shall not be less than 100 times. (3) The project with self flowing drainage conditions shall be provided with self flowing drainage system. Mechanical drainage system shall be provided for works without artesian drainage conditions, leakage or emergency drainage.