Common Leakage in Basement of Construction Engineering and Its Solution Measures Five common causes of leakage in underground part 1Installation of water-proof steel plate 2Leakage of post-pouring strip 3Protection of waterproof materials 4Closure of pipeline through wall position 5Waterproof closure at outdoor terrace 1. The incorrect setting of water-proof steel plate (position, connection, etc.) can easily lead to serious leakage. The incorrect location of the water-proof steel plate or the unsatisfactory quality of the installation result in serious leakage at the bottom of the basement wall. Cause analysis (1) The improper treatment of the weld seam at the overlap position of the water-proof steel plate is liable to cause potential leakage hazards. (2) At the corner of the wall, the position of the water-proof steel plate crosses with the stirrups, and the position of the water-proof steel plate is prone to deviate. The welding seam of the water-proof steel plate in this area is prone to leak welding, light transmission and other phenomena. (3) The thickness of the water-stop steel plate does not meet the requirements installation and of the welding, specifications. deformation centralized position are prone to occur. and During non- (4) incorrect installation direction of water stop steel plate. Countermeasures 1Technical measures: (1) The gauge thickness of water-proof steel plate is 2-3 mm, and 3 mm is preferred. (2) L-shaped finished water-proof steel sheet can be used at the corner of the wall.At the corner of the wall, the stirrups can be estimated to be disconnected and made into open stirrups, which are welded on the water-stop steel plate. (3) If the conditions are met, the rubber water-stop belt should be chosen as far as possible, and its effect is better than that of the water-stop steel plate. 2Acceptance emphasis: (1) The overlap part of the water-stop steel plate should be fully welded on both sides, and the overlap length should not be less than 20 mm. (2) Waterproof steel plate should be arranged in the middle, fixed welding, can be used to attach small steel bar welding support, avoid direct welding of water-proof steel plate and main bar. (3) When installing, the two warping surfaces of the water- stop steel plate should be oriented towards the waterfacing surface. 2. Leakage of post-pouring strip The construction period of post-pouring zone is longer and links are more. Detailed treatment is prone to deviation and leakage. Cause analysis (1) Because of the pressure of construction period and the early time of concrete pouring in post-pouring zone. (2) The water stops on both sides of the post-poured strip are not fixed firmly, resulting in displacement, which leads to the inconsistency of the first concrete thickness. (3) After the first placement of the post-pouring strip, the steel bar tramples and deforms, and even combines with the pipeline box with the inner line to form a water-crossing passage. (4) The reinforcement is dense, the supporting formwork on both sides of the post-pouring belt is difficult, the obstruction method is inappropriate, concrete is loose due to grouting leakage. and the (5) The steel bar in the post-pouring zone is seriously corroded.The ash and slag in the bottom slab joints have not been thoroughly cleaned and the old concrete on both sides has not been chiseled. (6) The grade of shrinkage-compensating concrete used in post-pouring zone has not been improved, the amount of micro-expansion agent is less, the slump of concrete is not strictly controlled, the vibration is not meticulous, and the combination of new and old concrete is not firm. (7) If the maintenance is not covered in time, the times of watering are few, and the maintenance period does not reach the prescribed time, the mould will be demolished earlier. Countermeasures 1Technical measures: (1) Before the construction of both sides of the post-poured strip, the drawing should be optimized to avoid the installation of pipelines and boxes in the strip as far as possible. (2) The pouring time of the post-pouring zone: the general period of concrete is 6 weeks. When the design is not required, the concrete should be poured after two months of age on both sides of the zone, and the pouring time of the concrete in the zone should be approved by the design. (3) Shrinkage-compensating concrete should be used for post-poured concrete.