What is formwork plywood?
It consists of a panel and a support system, the panel is the part that shapes the concrete; the support system is the part of the structure that stabilizes the panel position and bears the upper load. The quality of the formwork is related to the quality of the concrete project. The key lies in the accurate size, firm assembly, tight joints, and convenient assembly and disassembly. The appropriate form of formwork should be selected according to the form and characteristics of the structure in order to achieve good technical and economic effects. The formwork and support system of large and special projects should be calculated to check its rigidity, strength, stability and ability to withstand lateral pressure.
Material requirements
1. The base formwork is made of pine board, and the thickness of the side board of the ground beam is 20mm.
2. The bottom formwork of the main beam is made of pine boards, the thickness of the bottom formwork is 40mm, and the column formwork and floor formwork are made of machine-made wooden formwork (9-ply) with a formwork thickness of 12mm.
3. The support system is made of fir logs, the diameter of the small head is not less than 70mm, and the size of the small square wood is 400×500mm for the pulling connection, and the bottom support system is steel pipe support.
4. The wood formwork and supporting system shall not be brittle, easily distorted and deformed by moisture.
Foundation construction
1. Ensure the accuracy of the shape, size and mutual position of each part of the concrete structure and components.
a. Set 40×60mm total length of wooden blocks and 40×60mm short wooden blocks with a spacing of 1000mm on the upper and lower side molds, and support and fix the base groove wall on the outside of the short wooden blocks to meet the shape, size and position of the components accuracy.
b. The internal dimensions of the components are fixed when using fixed-length wooden blocks on the inner side of the side mold, with a spacing of 1000mm. When the height of the foundation beam exceeds 700mm, a double-strand lead wire is drawn in the middle of the side mold with a spacing of 1000mm to prevent mold expansion.
2. To ensure the strength and stability of the formwork stiffness requirements:
a. Use a template of 400 × 500mm to cushion the contact between the inner wall of the foundation groove and the support to ensure that the template has sufficient strength.
b. Use a 60×80mm wooden block to fix the upper part of the foundation beam as a whole to ensure that the formwork has sufficient stability.
c. Under the side formwork, nail the spacing of wooden feet with a distance of 1000mm (pull out after pouring) to ensure that the formwork has sufficient rigidity.
3. It is necessary to ensure that the structure is simple, the disassembly and assembly are convenient, and it is convenient for the binding and installation of steel bars and the pouring and maintenance of concrete.
4. Ensure that the joints of the formwork are tight to prevent leakage.
Safety Precautions
1. The formwork support shall not use rotten, twisted and other wood, the top support should be vertical, the bottom end should be flat and solid, the dunnage should be added.
2. The formwork should be carried out according to the procedure. Before the formwork is fixed, the next procedure should not be carried out. It is forbidden to use the tie rod to support climbing up and down.
3. The pillar formwork above 4.0m must be firmly supported around it. A workstation should be set up during operation. A horse bench can be used for operation if it is not 4.0m. A temporary working platform should be set up for supporting the group beam formwork, it is also not allowed to stand on the column formwork for operation and walk on beam formwork.
4. The dismantling of the formwork should be approved by the on-site constructor, and the important parts must be approved by the company’s quality and safety department. The operation should be carried out in sequence, and it is strictly forbidden to pry, smash or pry off and pull down in a large area. After completion, no loose and hanging formwork shall be left, and the formwork under the mark shall be transported to the designated place for centralized stacking in time to prevent iron nails from tying the feet.
5. No one should stand under the demoulding to prevent a sudden fall from hurting people.