Rapidly on-site. Plugging the leak is crucial; after on-site consultation, divers must be deployed to explore and initiate underwater plugging. Upon the director's immediate order for divers to arrive overnight, four divers arrived and dived in. Amidst strong currents, the divers descended but maintained stability, successfully plugging the leak underwater.
Operate according to modern enterprise management models. Comply with the requirements of the Provincial Construction Department, the Municipal Construction Committee, the client unit, and the environmental protection department in terms of civilized construction, quality follow-up, and lifelong responsibility. We are willing to contribute our due share to the innovation and application of waterproofing and leakage prevention technology, and sincerely welcome enterprises, units, and individuals to consult and negotiate by phone or in person.
In major and medium-sized hydroelectric and water conservancy projects such as the Yangtze River Three Gorges, the Yellow River Xiaolangdi, and the Wanzhai, despite various construction techniques being employed and strict quality assurance systems and control measures in place, various cracks have been found to some extent during concrete construction.
Cracks that form in concrete not only adversely affect its structure but may also pose direct threats to the entire building, especially hydrological structures. The presence of cracks in concrete, such as those underwater, can lead to leakage along the cracks, while cracks above the waterline can be further damaged by the repeated temperature changes, causing capillary water within the cracks to inflict additional harm on the structure, potentially leading to structural failure.
1. Project Manager 1 2. Supervisor 1 3. Safety Officer 1 4. Diving Team Leader 2 5. Divers 10 6. Crane Operator 2 Underwater Recovery and Underwater Object Recovery Engineering. Hot Searches: Construction teams specializing in underwater operations, with strong capabilities, serving: rivers, lakes, seas, reservoirs, and other underwater engineering projects. The company maintains a positive corporate image and strong competitive advantages. Since its establishment, the company has adhered to the people-oriented principle, honest business operations, and high-quality, efficient, dynamic services.
Underwater cutting of bridges, concrete, etc., providing diving operation services for various owners and construction units such as ports, bridges, shipyards, power plants, reservoirs, etc. With a broadminded spirit and an indomitable will, Huahang Company is committed to the diving engineering industry. The company has always adhered to the diving operation philosophy of "people-oriented, diving expertise, continuous improvement, and customer satisfaction": "Unite in purpose." Our diving services undertake local diving operations, with a response time of within an hour. Before diving construction, it is essential to understand the water depth, current speed, weather, and ensure there are no obstructions in the upstream and downstream of the underwater operation site. Our diving team is proficient in cooperation, strictly follows operational procedures, and efficiently completes various underwater tasks. Trust us, and we will undoubtedly deliver the underwater engineering services you desire.
Surface treatment should be applied to cracks with requirements for anti-corrosion, anti-seepage, anti-erosion, and abrasion resistance. Services include: basement leakage prevention, tunnel leakage prevention, sewage pool leakage prevention, culvert leakage repair, pond leakage prevention, underwater leakage prevention, dock leakage prevention, mine leakage prevention, cable trench leakage prevention, civil defense project leakage prevention, expansion joint leakage prevention, junction joint leakage prevention, crack leakage prevention, pump house leakage prevention, settlement joint leakage prevention, dam leakage prevention, underground engineering leakage prevention, elevator shaft leakage prevention, junction joint leakage prevention projects, cooling tower leakage prevention, construction joint leakage prevention, underwater leakage prevention, and various waterproofing and leakage prevention projects!
1. Temperature difference variation
The basement construction spans from summer to autumn, with the focus on the transition period between the two seasons. The construction timeline and backfill completion indicate that the basement concrete is significantly affected by seasonal temperature differences and internal-external temperature differences during this period, with a significant temperature range of up to 33°C. The main cause of the deformation in the expansion joints can be attributed to the horizontal shrinkage induced by the temperature differences.
2. Gasket installation position is inaccurate
Misalignment in positioning; the waterstop at the expansion joint in the basement is twisted and misaligned upon installation, severely out of place. The hollow circular ring in the center of the waterstop does not align with the center of the expansion joint, affecting the waterstop's ability to adapt to deformation. Additionally, improper fixation methods often result in the waterstop not being securely fastened.
3. The waterstop does not fit tightly with the concrete on both sides.
When installing horizontal waterstop on the base plate, it is difficult to compact the concrete beneath the waterstop, often resulting in honeycomb and rough surfaces. Additionally, after the evaporation of moisture between the waterstop and concrete, gaps are left, becoming pathways for water leakage. During the pouring of concrete on both sides of the vertical expansion joint, inadequate compaction occurs.
4. Lack of effective protection for rubber waterstop strips
When there is a difference in the pouring time of concrete on both sides of the expansion joint in the basement, there is an insufficient effective protective structure for the exposed half of the waterstop to be embedded in the post-poured concrete section, or protective measures are damaged during construction. Additionally, the waterstop may also be damaged or cut by nails, rebar, and other sharp tools during construction.
5. Construction Tolerance
The underlay, wall panels, and ceiling expansion joints all have corresponding design nodes. During construction, the work was not completed according to the design nodes, but the dimensions and construction meet the design requirements.
Section 2: Repair Plan for Waterproofing of the Basement Expansion Joints
1. Construction Preparation
(1) Conduct on-site inspections to identify the location, quantity, and flow of leakage in the basement expansion joints. Select appropriate waterproofing structures based on the severity of the leakage.
(2) If the water volume is substantial, initial grouting to seal leaks can be done first, reducing the water flow path before removing or demolishing the decorative layer; for lesser water volume, removing the decorative layer first can facilitate subsequent construction.
(3) Select qualified materials and components according to the established detailed plan.
(4) Surface to be cleaned, swept, and thoroughly washed, ensuring the base is a concrete structure layer without any slurry, and is level. If not level, local sanding or high-performance composite cement mortar can be used to level it. In case of local leakage during cleaning, perform grouting treatment, extending the grout into the rubber waterstop at the upstream side of the leakage point to ensure there is no leakage during construction.
2. Set non-adhesive post-tensioned reinforcing steel
In the concrete structure of the basement expansion joints, unbonded post-tensioned steel tendons are installed. The prestress is applied after the structure is completed and reaches its strength, causing the concrete structure to be pre-compressed. This helps resist tensile stresses due to drying shrinkage and temperature deformation, thereby reducing and preventing cracks in the concrete.
3. Concrete Repair
During the repair and reinforcement of the basement expansion joint, oblique injection holes are pre-leveled in the concrete on both sides of the joint. Detachable waterstop strips are installed on the bottom and wall panels. Reinforced concrete挡boards and joint materials are set on the exterior of the wall joints, and a coping wall is installed on the roof. The embedded waterstop strips on the roof are placed above the coping wall, and a gutter is set at the bottom of the roof joint.
4. Concrete uses compensating shrinkage
Compensating shrinkage concrete is a type of concrete that incorporates an expansive agent or expansive cement, resulting in a self-stress of 0.2MPa to 0.7MPa. This compensating shrinkage concrete can generate a pre-compressive stress of 0.2MPa to 0.7MPa through hydration and hardening within the concrete. This pre-compressive stress can fully or partially offset tensile stresses caused by drying shrinkage, creep, and temperature changes in the concrete, thereby enhancing the crack resistance of the concrete in the basement expansion joint area.
Additionally, self-compensating shrinkage concrete expands during hydration, reducing the pores in cement stone and effectively filling them, thereby significantly enhancing the overall anti-seepage performance of the project. The main applications of self-compensating shrinkage concrete in building structures include: self-sealing structures, seamless construction of ultra-long reinforced concrete structures without post-casting strips, and control of cracking and seepage in large-volume concrete. In practical engineering, these three situations may exist individually or interact with each other. By employing the construction technology of self-compensating shrinkage concrete, these technical challenges can be addressed collectively.
With 20 years of practice and experience in underwater diving operations (sunken ship/wreck recovery, underwater cutting, welding, dredging, gate repair, municipal pipeline sealing and removal, caisson construction, and various other underwater projects), we have accumulated extensive expertise. Our work has been recognized and praised by departments such as China Railway, China Communications Construction, Bridge Bureau, Water Conservancy and Hydropower, and more. Our diving team at Hua Hang Company ensures thorough preparation before any dive, as the safety of divers and the successful completion of diving tasks are crucial throughout the dive process. Preparations must be meticulous and thorough to guarantee diver safety and facilitate smooth diving operations. Analyzing the dive site and formulating dive plans are essential. The diving team ensures that all participants are well-informed, confident, apply the right methods, work efficiently, and achieve excellent results. Prior to diving, the surface and diving equipment, along with any additional gear, must be fully prepared, taking into account the conditions of the dive area and potential damage during the dive. This is an instinctive approach we've honed over time, with strict workmanship being a consistent requirement for our team. We firmly grasp our responsibilities and deliver high-quality construction. We will continue to maintain the standards for all underwater operations and perfect the quality of our diving services. Trust us to provide you with outstanding underwater services, with the capability to arrive on-site within 2 hours for special circumstances.
