Prefabricated component lifting technology
1) Production and transportation of prefabricated components.
Stacking is generally not more than 4 layers. The upper layer and the lower layer should be separated by layers. The pouring of the upper layer components should not be performed until the concrete of the lower layer reaches 30% of the design strength. The concrete strength requirements for the transport of the components are: If the design is not specified, it should not be less than 75% of the designed concrete strength standard value.
2) Planar layout of components
3) Lifting of prefabricated components
a. The binding of the column. In general, small and medium columns are tied together; heavy columns or columns with small and slender reinforcements are often bundled at two or more points to reduce the lifting moment of columns.
b. Column lifting. According to the characteristics of column movement during column lifting, it is divided into rotation method and sliding method. The main point of the rotation method is to keep the position of the column foot and make the column's hanging point, the center of the column foot and the center of the cup co-circle. It is characterized by less vibration in the lifting of the column, but it requires high mobility of the crane. The main point of the gliding method is that the hanging point of the column should be arranged beside the mouth of the cup; Its characteristic is that the crane can lift the column in place only by turning the boom, which is safe, but the column is subject to vibration during taxiing. Therefore, this method is only used when the crane and the venue are limited.
2 crane beam hoisting. Joint concrete reaches 70% of design strength.
Hoisting of 3 roofs.