This project.
The weak links of waterproofing are mainly manifested in the compactness of waterproof concrete, the treatment measures of construction joints, post-pouring belts, the treatment measures of membrane joints, the quality of waterproof materials, and the operation process. In order to ensure that the waterproof quality meets the design requirements, the following measures are taken during construction:
1. Strengthen the control of raw materials, and the waterproof material must be composed of technical data such as certificate and retest report, as well as technical indicators such as the dosage and performance of waterproof materials.
2. The configuration of waterproof concrete must be in accordance with the mix ratio presented by the laboratory, and the measurement management must be strengthened in operation. The mix ratio of waterproof concrete should be strictly controlled, not only to take into account the waterproof effect of concrete, but also to take into account the pumpability of concrete. The dosage of admixture is determined according to the design requirements and laboratory ratio test.
3. The mud content of sand, stone and other materials must be controlled within the allowable range, and it is strictly forbidden to exceed the standard.
4. The mixing, pouring, vibration, and maintenance of concrete should be carried out in strict accordance with the provisions of the construction and acceptance specifications and operating procedures.
5. Concrete pouring should be layered, the thickness of each layer should not exceed 30 40cm, and the pouring time interval between two adjacent layers should not exceed 2h.
6. Waterproof concrete should be vibrated mechanically, not manually.
7. The curing of waterproof concrete has a great impact on its impermeability, especially the early wet curing is more important, generally when the concrete enters the final setting, it should be covered, and the watering and moist curing is not less than 14d.
8. It is strictly forbidden to make holes after the concrete waterproof structure is poured. The embedded iron parts and reserved holes in the waterproof concrete structure, as well as the post-pouring joints of the structure, are all weak points that may lead to water leakage, and measures should be taken to carefully construct them. It is forbidden to use a wall sleeve on the exterior wall, and there should be a waterstop, and the width of the waterstop should not be less than 50mm.
9. The construction joint is one of the weak parts of the waterproof, and the construction joint should be left no or less. The vertical construction joints of the wall should be unified with the post-pouring belt, and no other vertical construction joints should be left. The lowest horizontal construction joint is 500mm away from the bottom plate surface, not less than 300mm away from the edge of the hole through the wall, and is avoided at the part where the wall panel bears the greatest bending moment or shear force.
10. Before pouring the seam of the post-pouring belt, the surface of the joint should be chiseled to remove floating particles and debris. Before continuing to pour concrete, rinse with water and keep it wet, and lay a layer of cement mortar 20 25mm thick, the material and lime-sand ratio should be the same as that of concrete. After compacting, continue to pour concrete.
11. The concrete of the post-pouring belt should be made of compensating shrinkage concrete, and the strength grade should be one strength grade higher than the strength of the concrete poured first on both sides. The position, form and size of the post-pouring belt should be constructed in accordance with the design regulations.
12. The post-poured concrete shall be poured after 60 days of concrete pouring on both sides according to the design requirements.
13. The base layer of the flexible waterproof layer must be dry before construction, and the moisture content should be less than 9%.
14. During the construction of waterproof membrane, before paving the membrane, where the unevenness must be smoothed and compacted with 1:3 cement mortar, the cracks and joints must be leveled with caulking materials, and the concrete honeycomb and hemp surface should be chiseled first, and the waterproof mortar should be leveled, and the additional layer of horizontal construction joints, concrete honeycomb, hemp surface and other places must be laid, and then the membrane waterproof layer should be made.
15. To control the interval of adhesive brushing, it is generally required that the adhesive coated on the base and coil material reach the degree of surface dryness, usually 10 30min, which can be determined by experience during construction, and can be touched with fingers when it is not sticky.
16. When paving the waterproof membrane, the membrane must be tightly and flat, and must not be wrinkled. The lap joint between the coils must overlap 7 10cm, and the lap joints of the coils should follow the dominant wind direction. The thickness of the paint should not flow.
17. During the construction of the coating, it should be continuously and evenly brushed, so that the thickness is uniform, no accumulation, no flowing, no leakage, and the second construction can only be carried out after the same coating film is dry, otherwise the water will not be volatilized, causing bubbles to be generated, and affecting the waterproof effect.