**Construction Methods and Steps for Steel Plate Rubber Waterstop:** When constructing the base slab reinforcement, it is essential to effectively connect the waterstop steel plate with the base slab reinforcement. A door-shaped support frame can be made from #12 rebar and fixed above the base slab reinforcement, with welding used between the door frame and the waterstop steel plate. The specific steps are as follows: 1. First, fix two pieces of #12 rebar vertically to the base slab. Place the waterstop steel plate between the two rebar pieces, then penetrate the waterstop steel plate with a horizontal rebar. Weld a waterstop ring on top of the horizontal rebar and ensure a full weld connection between the waterstop ring and the waterstop steel plate. The width of the waterstop steel plate should not be less than 400mm, with 200mm buried in the base slab concrete. The initial concrete pour should be at least 200mm above the top surface of the base slab. The thickness of the steel plate should be no less than 3mm, and to ensure the steel plate has sufficient rigidity during construction, the edges of the steel plate should be folded 50mm on both sides, at an angle of approximately 30 degrees. 2. Once the waterstop steel plate is generally in position, minimize the gaps between the steel plates. Overlapping welding can be used for the joints between steel plates, with an overlap length greater than 400mm, and the weld must be a full weld. Compared to rubber waterstops, the advantages of steel plate waterstops are not as pronounced, with a significant disadvantage being rust, which complicates later treatment. Therefore, it is advisable to use rubber waterstops as much as possible. (Here, a brief introduction to the installation requirements for rubber waterstops: the waterstop is partially or fully embedded in the concrete during the concrete pouring process. Due to the many sharp stones and rebar heads in the concrete, the tearing strength of plastic and rubber is 3-5 times lower than their tensile strength. Once the waterstop is pierced or torn,) 3. A small external force can easily cause the crack to expand. Therefore, during the positioning of the waterstop and the pouring of concrete, special attention should be paid to the positioning method and the pouring pressure to avoid piercing the waterstop, which would affect the waterstop's effectiveness. Regarding installation direction, whether it is a horizontal or vertical steel plate waterstop, the two curved surfaces must face the water pressure. 4. Waterstops are generally installed at the location of construction joints, on the side walls of basements with waterproofing requirements, or at expansion joints, which are exposed for long periods. Proper protective measures should be taken, such as applying anti-rust paint. **Leakage Prevention Measures for Steel Plate Rubber Waterstop:** ① Adopting a joint form suitable for the engineering characteristics of the construction joint and the waterproofing methods for the concrete on both sides is key to effective leakage prevention measures. Typically, a tongue and groove joint or step joint should be used, and a combination of waterstop strips or waterstop belts should be placed in the middle of the joint. ② If steel plate waterstops are used for waterproofing, the joints of the steel plate waterstops must be lap welded, with a lap length of ≥50mm. Welding must be done in all four directions, with full penetration and no slag inclusions, burn-through, or bubbles. ③ Apply two coats of flexible elastic putty at the construction joint locations on internal walls and ceilings to prevent small cracks from forming due to structural settlement and expansion. ④ If advanced waterproofing is needed at the construction joint, the concrete in that area should be locally thickened, and external or embedded waterstops should be added. ⑤ The construction joint should use shrinkage-compensating micro-expansion concrete, with the strength grade increased by one level.