What is the function of a waterstop? (External wall waterstop)

Metal waterstops, made of metal plates, alter the water seepage path and extend its reach.

In construction environments where leaking water may contain corrosive components, metal plate waterstops provide some corrosion resistance.

In protective engineering projects, the use of metal plate waterstops ensures the project's protective effect.

Metal plate waterstops are also commonly used in projects with high impermeability requirements and small areas, such as casting pits in smelters and electric furnace foundation pits.

Materials include steel plates, copper plates, and alloy steel plates.

Rubber waterstops are partially or completely embedded in concrete during the concrete pouring process. Concrete contains many sharp-edged stones and sharp rebar ends. Because the tear strength of plastics and rubber is 3-5 times lower than their tensile strength, once a waterstop is punctured or torn, the crack will widen quickly without significant external force. Therefore, careful attention should be paid to the positioning method and pouring pressure during waterstop placement and concrete pouring to prevent puncture and ensure effective waterstop performance.

For steel plate waterstops in box-type foundations or basements, where the concrete for the base slab and exterior wall panels is poured separately, a construction joint is created when the wall panel concrete is poured later. If this joint is below the groundwater level, seepage is likely to occur.

This necessitates technical treatment of the joint. Many methods exist, with the installation of a waterstop steel plate being a common approach.

This involves pre-embedding a 300mm x 3mm steel plate during the pouring of the lower layer of concrete, with 10-15cm of the top portion exposed. This exposed portion is then poured into the next layer of concrete to prevent the infiltration of pressurized water.

The thickness of the steel plate waterstop is typically 2mm to 3mm.

Exterior Wall Waterstop Retaining Wall Construction (Exterior Wall Waterstop Construction Method)

Hello, steel plate waterstops must be pre-embedded on both sides of the exterior wall post-pouring strip, following the construction joint method. Before pouring the exterior wall concrete, a dense steel mesh with sufficient strength to prevent concrete loss is installed on both sides of the post-pouring strip. The steel mesh is welded to and securely fixed to the steel plate waterstop.

An additional waterproof layer must be installed on the exterior of the exterior wall post-pouring strip, extending at least 300mm beyond the strip on both sides.

The formwork for the exterior wall post-pouring strip should be firmly reinforced to prevent bulging and grout leakage.

The concrete for the post-cast strip of the exterior wall should be poured simultaneously with the concrete for the post-cast strip of the basement roof slab, if possible.

After treating surface defects and sealing bolt holes, apply an additional waterproof layer. Once the additional layer passes inspection, apply the final waterproof layer. To facilitate timely backfilling of the basement exterior wall, complete the main exterior wall waterproofing first, then construct 240mm thick solid brick walls 1 meter apart on each side of the post-cast strip. After the post-cast strip concrete is completed, the waterproofing at the post-cast strip location should overlap with the waterproofing already applied on the main surface within the partition walls.

Hope this helps, thank you.

What should be noted during the construction of steel-edged waterstops? (Where are the waterstops located on the exterior walls?)

1. Steel-edged waterstops are generally placed in the middle of the base slab or pool wall. Before concrete is poured, they are essentially suspended in mid-air, merely clamped and fixed by formwork, without dedicated steel reinforcement frames or other reliable fixing measures. 1. Due to the high impact force of pumped concrete, coupled with the vibration of the vibrator, 300*8 embedded rubber waterstops often experience displacement and tilting.

2. Insufficient compaction of the concrete beneath the Huiye rubber steel-edged waterstop can cause localized free deformation of the waterstop. Under water pressure, this can also create large voids.

3. If the steel-edged waterstop is damaged during construction, resulting in cracks, and these are not detected or addressed promptly, leaks may occur. Since it's difficult to pinpoint the exact location of leaks on the pool bottom slab, complete rework is often necessary.

The "S" and "B" in the term "steel-edged waterstop" represent different tensile strengths. The tensile strength of S-type steel edge waterstop is 10 MPa. The tensile strength of B-type rubber waterstop is 16 MPa. Other physical and mechanical parameters may also differ. B-type steel edge waterstop has strong adaptability to deformation and good waterproof performance. The temperature range for use is -40℃ to +60℃. When the temperature exceeds 70℃, or when the waterstop is subjected to strong oxidation or corrosion by organic solvents such as oil, it shall not be used.