News Abstract: the construction joint of waterproof layer needs to leave slope stepped tenon, and should be constructed continuously according to the level operation sequence, and the layer by layer is closely overlapped. Generally, the position of the tenon should be left on the ground or on the wall, but it should be 200 mm away from the internal and external corners.
1. General provisions for cement mortar waterproof layer:
(1) The surface of base course shall be flat, solid, rough and clean. The surface of cement mortar waterproof layer shall be fully wet without ponding.
(2) The waterproof layer of cement mortar mixed with additives shall be paved in two layers regardless of the upstream surface or the back surface. The surface shall be calendered and the total thickness shall not be less than 20 mm.
(3) The consistency of cement mortar should be controlled at 70 ~ 80mm, and the cement mortar with less water should be used as soon as mixing.
(4) The internal and external corners of the structure shall be rounded. The radius of circular arc is generally 50 mm, and the external angle is 10 mm.
The construction should be carried out in accordance with the sequence of continuous construction. Generally, the position of the tenon should be left on the ground or on the wall, but it should be 200 mm away from the internal and external corners.
2 construction preparation
(1) Check the drawings before construction and prepare the construction scheme of waterproof engineering. The operators of underground waterproof engineering shall work with certificates.
(2) The base course paved with waterproof layer must be completed according to the design and dried after curing, with the moisture content no more than 9%; the base course should be flat and firm, free from hollowing and cracking and large sand.
(3) The surface of the base course shall be cleaned before the primer is applied in the waterproof layer construction.
(4) Construction materials are flammable, so the corresponding fire-fighting equipment should be prepared.
3 operation process
(1) Process flow:
(2) Base cleaning: clean up the qualified base before construction.
(3) Brush the base treatment agent: brush a layer of chloroprene rubber asphalt adhesive diluted with gasoline on the surface of the base course, which should be uniform and impervious to the bottom.
(4) Lay additional layer: lay a layer of coiled material on the pipe root and internal and external corners. According to the requirements of the design, the coiled material shall be cut and laid.
(5) Paving coiled material: cut and roll the modified asphalt waterproof coiled material according to the paving length. During operation, insert the coiled material into the coil core with a diameter of 30, align the end of the coiled material with the starting point of paving, ignite the gasoline blowtorch or special flame spray gun, heat the junction between the base course and the coiled material, keep the distance between the spray gun and the heating surface about 300 mm, spray and bake and observe the rolling When the asphalt of the material is just melted, the two ends of the pipe core should flow forward and laid slowly, with uniform force and no air entrapment. The width of laying blank holder should be well controlled. The lap width of full paste method is 80 mm, and that of strip bonding method is 100 mm.
(6) hot melt sealing: cement mortar or fine aggregate concrete protective layer shall be made on the plane; after the construction of facade waterproof layer, the cement mortar protective layer shall be plastered after sparing the ballast in time.
4 quality standards
(1) Guarantee items: the specification, performance and mix proportion of polymer modified asphalt waterproof membrane and adhesive must be adopted according to the design and relevant standards, and the qualified factory certificate shall be provided.
Special waterproof layer and construction method are strictly prohibited, and the waterproof layer must meet the design requirements.
(2) Basic project
The base course should be flat without hollowing and sand, and the internal and external corners should be circular or obtuse.
The modified asphalt adhesive shall be applied evenly without missing brush, bottom penetration and pitting.
The width of the additional layer of the waterproof layer of the coiled material shall meet the requirements of the specification; the lap width of the joint of the layered layer shall meet the requirements of the specification, and the end shall be embedded firmly.
The coil shall be firmly bonded without any defects such as hollowing, damage, slipping, warping, blistering and wrinkling.
5 Protection of finished products
(1) The pipes embedded in the waterproof layer of underground coiled materials shall not be damaged or blocked during construction.
(2) The protective layer shall be made in time after the waterproof layer is paved to prevent the structure construction from damaging the waterproof layer; after the construction of the external waterproof layer, the protective wall shall be built according to the design.
(3) During the construction of roll proof plane waterproof layer, materials shall not be placed on the waterproof layer or used as construction transportation lane.
6 quality problems that should be paid attention to: (1) poor lap joint of coiled material: Joint lap form and joint width of long side and short side are too small, bond at joint is not dense, joint is damaged and hollowing; during construction operation, standard line should be snapped according to the procedure to make it conform to the specification of coiled material. During operation, the long side and short side of coiled material should not be less than 100 mm and 150 mm respectively.
(2) Hollowing: the base course paved with coiled materials is wet, uneven and unclean, resulting in air void and hollowing between the base course and the coiled material; the air is not completely exhausted during laying, which can also cause hollowing among the coiled materials; the base course shall be fully dry during construction, and the coiled material shall be evenly compacted.
(3) poor adhesion of waterproof layer at pipe root: unclean cleaning, shape matching between cut coil material and root, and unsound edge pressing, etc. during construction, the cleaning shall be thoroughly cleaned, attention shall be paid to the operation, and the coiled material shall be compacted without mouth opening, edge warping and wrinkling.
(4) Leakage: the corner, pipe root and deformation joint are not easy to operate and leak. During the construction, the additional layer should be operated carefully; the joint coil material should be well protected, and the lap joint should meet the width requirements to ensure the construction quality of special parts. (5) the waterproofing of various construction parts shall be carried out according to different technical specifications. The layer waterproofing of guard room is 20 thick cement mortar leveling layer, two felt and three oil waterproof layer; the ground is 20 thick cement mortar protective layer, and polyurethane waterproof coating is 1.5 thick. Water pool waterproof is 20 thick cement mortar leveling layer, SBS waterproof coating and 20 thick cement mortar protective layer.