How to control the waterproofing and anti-seepage construction technology of building infrastructure?

Recently, with the high-quality development of China's construction industry, the durability and safety of building infrastructure have received widespread attention. Waterproof and anti-seepage construction, as the core link of building quality control, directly affects the building's functional use, service life, and living experience. The waterproofing and anti-seepage construction of building infrastructure covers multiple key areas such as basements, roofs, exterior walls, kitchens and bathrooms, and underground pipelines. It is affected by various factors such as material quality, construction technology, and environmental conditions. If not properly controlled, problems such as leakage, moisture, and mold may occur, which not only affect the normal use of the building, but may also damage the internal structure and increase maintenance costs in the later stage.
The construction technology control of waterproofing and anti-seepage in building infrastructure follows the core principles of "prevention first, systematic control, full process monitoring, and adapting to local conditions", which runs through the entire process of construction preparation, on-site construction, post acceptance, and maintenance. The core goal is to build a complete and reliable waterproofing and anti-seepage system to eliminate leakage hazards. Industry experts say that waterproofing and anti-seepage construction is not a single link of control, but a collaborative effort of materials, processes, personnel, environment, and other aspects. It is necessary to strictly follow industry standards and accurately control every technical detail in order to achieve long-term waterproofing and anti-seepage of building infrastructure.

The technical control during the construction preparation stage is the foundation of waterproof and anti-seepage construction, and also the primary link in preventing leakage hazards. It mainly covers core points such as material control, scheme preparation, personnel training, and on-site preparation, among which material quality control is of paramount importance. Waterproof and anti-seepage materials are the core carrier for building waterproof systems, and their quality directly determines the effectiveness of waterproofing and anti-seepage. They need to be strictly screened and accepted according to design requirements and industry standards.

Before construction, the construction unit needs to conduct strict inspections on core materials such as waterproof rolls, waterproof coatings, sealing materials, and waterproof concrete, verify the specifications, models, quality certificates, and qualification certificates of the materials, and ensure that the material performance meets the design requirements and GB 55030-2022 standard specifications. For waterproof concrete, it is necessary to ensure that the cement used is Portland cement or ordinary Portland cement, the maximum particle size of the stones is not greater than 40mm, and the water absorption rate is not greater than 1.5%; For waterproofing membranes, it is necessary to focus on testing their joint peeling strength, water resistance, and other indicators. The performance retention rate after thermal aging should not be less than 80%; For sealing materials, the quality loss rate should be controlled, with silicone materials not exceeding 8% and polyurethane materials not exceeding 10%. At the same time, the storage and preservation of materials should be standardized. Waterproof rolls and coatings should be stored in dry and ventilated warehouses to avoid moisture and exposure to sunlight, and to prevent material aging and deterioration; Waterproof concrete raw materials need to be classified and stacked, and moisture-proof measures should be taken. In the construction of an underground garage in a large commercial complex in the south, the construction unit established a special material acceptance ledger, sampled and rechecked the incoming waterproof materials one by one, and prevented unqualified materials from being put into use, laying the foundation for subsequent waterproof and anti-seepage construction.

The preparation of construction plan is an important part of the construction preparation stage. It is necessary to combine the characteristics of the building structure, waterproof and anti-seepage parts, geological and hydrological conditions, and climate environment to prepare a special waterproof and anti-seepage construction plan, clarify the construction process, technical parameters, quality control standards, and emergency measures. After approval, it can be put into implementation. For high leakage areas such as basements and roofs, it is important to clarify the level of protection and construction details. For first level waterproofing, two or more layers of protection should be installed, and for second level waterproofing, one or more layers of protection should be installed. At the same time, professional training and technical disclosure should be provided to construction personnel to enhance their mastery of construction specifications, process points, and quality control requirements. Especially for special waterproofing operators, they must hold valid work permits before they can take up their posts to ensure standardized construction operations. In addition, before construction, it is necessary to clean up debris, oil stains, floating slurry, etc. at the construction site, repair cracks and depressions in the base layer, ensure that the base layer is flat, solid, and dry, and provide a good foundation for waterproof and anti-seepage construction.

The technical control during the on-site construction phase is the core of waterproof and anti-seepage construction. Targeted construction techniques and control measures should be adopted for different waterproof and anti-seepage parts, with a focus on controlling key links such as base treatment, waterproof layer construction, and node sealing, to eliminate quality hazards during the construction process.

Base treatment is a prerequisite for the construction of waterproof layers, and the quality of the base directly affects the bonding strength and waterproof effect of the waterproof layer. For concrete base, it is necessary to polish, clean, remove surface floating slurry and debris, and control the moisture content of the base within the allowable range of the specifications; For the roof and exterior wall base, it is necessary to ensure that the slope meets the design requirements and avoid water accumulation. Cracks in the base should be repaired with sealing materials to ensure that there are no cracks or looseness. The construction of the waterproof layer must strictly follow the construction plan and process requirements. The construction of the waterproof membrane must control the laying sequence, overlap width, and bonding quality. The overlap width must meet the specifications. During the laying process, the air between the membrane and the base layer must be eliminated to ensure a tight and tight fit between the membrane and the base layer, avoiding problems such as hollowing and warping; Waterproof coating construction should be evenly applied, with controlled thickness and number of coats to avoid omissions and uneven thickness. After application, wait for the previous coat to completely dry before proceeding to the next coat.

Node areas are weak links in waterproofing and anti-seepage, as well as high-risk areas for leakage, mainly including construction joints, deformation joints, post pouring belts, through wall pipes, internal and external corners, etc. Technical control needs to be strengthened. Construction joints, deformation joints, and post pouring belts shall be equipped with waterstops or waterstops in accordance with the specifications. Before pouring horizontal construction joints, the surface floating slurry shall be removed, and a layer of 30-50mm thick 1:1 cement mortar shall be laid before pouring concrete; The deformation joint shall be filled with polyethylene foam plastic rod, and the surface shall be filled with polysulfide sealant or silicone sealant; A waterproof sleeve should be installed for the through wall pipe, and a water stop ring should be installed in the middle of the sleeve and fully welded on both sides. The gap between the sleeve and the pipeline should be filled tightly with sealing material. In the Belinis Reservoir Repair Project in Mexico, the construction team used a professional crack repair system to seal the cracks in the bottom plate and side walls, and carried out special waterproofing treatment on the through wall pipelines, effectively solving the leakage problem and verifying the importance of node sealing control.

The waterproof and anti-seepage construction of different parts should take into account their usage characteristics and adopt targeted control measures. The basement waterproofing should follow the system concept of "structural self waterproofing+external waterproof layer", and the waterproof concrete anti-seepage grade should not be lower than the design requirements. The cast-in-place concrete should not be lower than P8, and the precast concrete should not be lower than P6. The foundation pit backfilling should be compacted layer by layer with a compaction coefficient of not less than 0.94, and construction waste and silty soil should not be backfilled; Roof waterproofing requires proper drainage design, and a closed water test must be conducted after the completion of the waterproof layer construction to ensure no leakage; Waterproof materials with strong weather resistance should be selected for exterior wall waterproofing, evenly applied to avoid cracks, and sealed around doors and windows; The waterproofing of the kitchen and bathroom needs to be painted to the specified height. After the completion of the waterproof layer on the ground, a closed water test must be conducted. Only after passing the test can subsequent construction be carried out.

During the construction process, it is necessary to strengthen on-site inspections and process monitoring, arrange professional technical personnel to supervise the construction process in real time, check whether the construction technology, material laying, node processing, etc. meet the regulatory requirements, and promptly discover and rectify quality hazards during the construction process. At the same time, it is necessary to keep construction records, detailing information such as material usage, construction parameters, and construction time, to ensure traceability of the construction process.

The technical control during the later acceptance and maintenance stage is the last line of defense for the quality of waterproof and anti-seepage construction, which directly determines the long-term effectiveness of the waterproof and anti-seepage system. During the acceptance stage, it is necessary to strictly follow industry standards and design requirements to conduct a comprehensive inspection of the waterproof and anti-seepage engineering, with a focus on checking the integrity of the waterproof layer, the quality of node sealing, and the effectiveness of the drainage system. Closed water tests, water immersion tests, and other methods are used to verify the waterproof and anti-seepage effects. Any parts that fail the acceptance must be rectified within a specified period of time, and can only proceed to the next process after passing the re acceptance.

Technical control during the maintenance phase is equally important. After the completion of the waterproof layer construction, it is necessary to protect the finished product to avoid damage to the waterproof layer. It is strictly prohibited to stack heavy objects or sharp objects on the waterproof layer; The maintenance of roofs, kitchens, bathrooms, and other areas should be carried out for a period of time to avoid premature use. At the same time, it is necessary to regularly inspect and maintain the waterproof and anti-seepage system. If leakage, damage, and other problems are found, timely repair measures should be taken to extend the service life of the waterproof and anti-seepage system.

The reporter learned that with the continuous development of the construction industry, waterproof and anti-seepage construction technology is also continuously optimized. The application of new waterproof materials and intelligent construction equipment has further improved the quality and efficiency of waterproof and anti-seepage construction. Industry experts remind that the control of waterproofing and anti-seepage construction technology for building infrastructure is a systematic project that needs to run through the entire construction process. Construction units need to strictly implement the quality responsibility system, strengthen control at all stages, strictly follow the mandatory standard GB 55030-2022, and optimize the construction plan based on actual conditions. In the future, we will further promote the refinement and green development of waterproof and anti-seepage technology, strengthen the research and application of new materials and processes, improve the quality control system, provide strong support for the high-quality development of building infrastructure, and help create safe, durable, and comfortable building spaces.