地下防水工程的“防”应由混凝土结构自防水和卷材柔性防水双道防线来保证。地下防水工程失败后的修补特别困难，所以保证地下防水工程的质量至关重要。在这里我们通过实例来探讨保证地下工程防水质量的途径。１选材要恰当地下防水工程所处的环境没有屋面的环境恶劣，地下温差 The “anti-prevention” of the underground waterproofing project shall be ensured by the self-waterproofing of the concrete structure and the flexible and waterproof double-line defense of the coiled material. Repair of underground waterproofing projects is particularly difficult after failure, so it is important to ensure the quality of underground waterproofing projects. Here we use examples to explore ways to ensure the waterproof quality of underground works. 1 The materials should be properly grounded. Waterproofing works in an environment where the roof is not in a poor condition. Underground temperature difference