蒸压加气混凝土砌块墙体裂缝质量通病 的启事剖析与把持办法 3(国外英文资料).docVIP

蒸压加气混凝土砌块墙体裂缝质量通病 的原因分析与控制措施 3(国外英文资料) Walls cracking are inevitably has its internal causes, according to the wall, the mechanism of cracking wall will produce larger crack will go through three steps: (1), the wall within the larger internal stress; (2) the stress concentration of internal stress in one part of the wall; (3), in the area of stress concentration, the tensile strength of masonry are not enough to counter the effect of stress concentration, cracks in the form of performance, this part of the stress concentration at the same time and continues to release, and gradually form a larger cracks thus! To reduce wall cracking problem, it must be from the several aspects to study the corresponding prevention and solution, is briefly described as follows: Reduce the internal stress in the whole wall Minimize the actual dry shrinkage of products such as wall materials (1) the wall material, which is less than 30 days old, is not used for the use of the wall material, which ensures that the new wall material has a relatively small amount of actual dry shrinkage and high strength before it is used. The drying shrinkage of the gas and gas concrete blocks should be less than half mm/m, and the compressive strength of the exterior wall is not less than 5MPa, and the compressive strength of the inner wall is not less than 3.5 MPa. (2) the brickwork shall not be used for masonry. Bricks should be stacked indoors or in dry places that are not affected by rain, snow or moisture. Before the first leather block masonry, should first wet the base level, water again spread M7.5 cement mortar, and the block bottom horizontal mortar joint and side vertical mortar joint with coating binder rear can masonry. The masonry of the second skin block shall be carried out after the initial clotting of mortar and cementing agent. The masonry surface of masonry should be flat, otherwise it is necessary to grind the ground and clean up the dust. When masonry block is made, the mortar se