Erection requirements for high support frame of beam and slab formwork
1. When erecting the upper bent, the ground concrete strength must be greater than 1.2n/ mm2, and the lower formwork support system must not be removed; Especially for parts with support height greater than 8 meters.
2. During the erection of the support frame, the beam sideline must be set out first, and then the vertical poles must be arranged according to the layout of bent vertical poles. The vertical poles are required to be in vertical and horizontal rows, and the diagonal bridging and transverse diagonal bracing must be erected synchronously with the vertical poles, longitudinal and transverse horizontal poles, and the lower end of each bottom diagonal pole must be supported on the concrete surface.
3. The spacing between the vertical and horizontal poles of bent erection shall be arranged in strict accordance with the dimensions in the attached drawings, and the step height shall not be greater than 1.5m. Vertical and horizontal sweeping rods shall be set no more than 200mm above the ground. The fasteners of the longitudinal and horizontal horizontal bars shall be fastened on the vertical bar. After each step, correct the step distance, longitudinal distance, transverse distance and the verticality of the pole.
4. A vertical diagonal bracing must be set up continuously from top to bottom every 1015 meters along both ends and the middle of the vertical and horizontal directions of the bent; A horizontal diagonal brace is set at the top, bottom and middle of the bent every two steps. The width of the diagonal brace is 68 meters, the spacing is 1015 meters, and the contact must be connected with the main upright. The included angle of diagonal bridging is controlled at 45. 60。 between.
5. The distance between the vertical poles of the slab support shall be controlled within 1.0m x 1.0m (the distance between the vertical pole and the beam bottom is 1
To) according to the calculation, the bottom of the beam and slab must be loaded by double fasteners.
6. Except for the overlapping of the top layer, the rest of the vertical poles adopt butt joint, and the overlapping length is not less than 1 meter and 3
Fasteners. When using butt fasteners for vertical connection, the number of butt joints and extensions of upright rods in the same horizontal plane
It shall not be more than 1/3 of the total number, and the extension point shall be within 1/3 of the distance from the end of the step
The long rods shall be evenly distributed within the plane of the bent. Synchronous lengthening of two adjacent vertical poles is strictly prohibited, and the lengthening of vertical poles should adopt the principle of minimum contact meeting the support height.
7. If the bottom of the opposite pole is not at the same height (between the two axes), the vertical sweeping pole at the top must be extended to the bottom for two spans and fixed with the upright pole. The horizontal bar at the additional vertical bar at the bottom of the beam must also be extended for two steps.
8. In order to prevent personnel from falling from height, the working layer under the formwork support must be paved with scaffold boards with a width of not less than 500mm as temporary walkways (mainly used for beam reinforcement binding and beam formwork reinforcement). The scaffold boards must be tied with steel pipes with 18 # iron wires, and safety nets must be hung under this layer. It is forbidden to use 50 X100 batten instead.