Applied measures, architectural design and construction of autoclaved lime-sand bricks can be carried out in accordance with the relevant specifications of sintered ordinary bricks. However, because some properties of autoclaved lime-sand bricks are quite different from those of sintered ordinary bricks, corresponding technical measures must be taken in use.
Anti-crack measures
① When calculating unreinforced masonry compression members, the value of the influence coefficient ψ should be determined by the height-thickness ratio and eccentricity. Autoclaved lime-sand bricks should multiply the height-thickness ratio of the member by the adjustment factor γβ(1.2).
② Reasonably set expansion joints. GB50003-2001 stipulates that the spacing of expansion joints of autoclaved lime-sand brick masonry houses should be 0.8 times the spacing of expansion joints of sintered ordinary brick masonry houses to reduce the spacing of expansion joints.
③Due to the shrinkage of the wall caused by the dry shrinkage of the blocks, a certain shrinkage stress is generated inside the masonry. When the tensile and shear strength of the masonry is not enough to resist the shrinkage stress, cracks will occur. Therefore, in the places where the stress is concentrated, such as the masonry above the door and window lintel and under the window sill, welded steel mesh should be installed to resist the stress caused by brick shrinkage. In addition, when the length of this type of wall is greater than 5m, it is easy to be pulled apart, so it should also be properly reinforced. The specific method is: design welded steel mesh or 2Φ6 steel bars in the horizontal gray joint above the door and window lintel and in the first and second horizontal gray joints under the window, and its extension into the wall between the windows on both sides is not less than 600mm; The length of the solid wall is greater than 5m, and 2 to 3 welded steel mesh pieces or 3Φ6 full-length horizontal steel bars are installed in the middle of each layer of the wall, and the vertical spacing is 500mm.
