剪力墙裂缝产生原因（Causes of cracks in shear walls）.docVIP

剪力墙裂缝产生原因（Causes of cracks in shear walls） With the development of architectural technology, the buildings is becoming higher and higher, the general high-rise building, the design is widely used in the design of cast-in-place shear wall structure, and use a large flow of pump concrete pouring construction. At the same time, the development of premixed concrete also poses a problem - the structure cracks, if cracks, the overall performance and seismic performance of leakage or influence the structure will lead to the building, so the wall cracks should be paid more attention. Key words: shear wall; cracks; reasons; control measures Causes of cracks in 1 wallboard Shear wall cracks are mainly caused by concrete shrinkage cracks, strong constraint cracks, cracks caused by building shape; cracks outside the force. 1.1 concrete shrinkage of the three cases 1.1.1 dry shrinkage of concrete in the preparation process, the volume expansion of cement and admixture and water after mixing, but in casting, with concrete hydration, part of the water in the concrete absorbed part of the evaporation of water volume, there is a certain degree of narrowing. Concrete volume shrinkage, so that concrete produced internal stress, when the contraction and contraction of large, concrete cracks. 1.1.2 concrete internal temperature changes to produce shrinkage cracks and walls of the part of the frame column, the length of the section is greater than 1m, is a large volume of concrete, hydration heat high, if taken improper measures, surface concrete will produce cracks. For the joint of frame column and exterior wall, the frame column of large volume concrete can be regarded as a large heat source body, and the connecting wall is thin, and the contact surface with the outside air is large, and the heat dissipation is fast. When a large number of columns in the heating expansion, the wall has begun to cool contraction due to temperature difference in the link between the two components toget