What causes the deformation of the building template?

 

The building formwork structure used in the construction of cast-in-place concrete structures is mainly composed of three parts: panels, supporting structures and connectors. The face plate is the bearing plate that directly contacts the newly poured concrete; the supporting structure is the temporary structure that supports the face plate, concrete and construction load to ensure that the building formwork structure is firmly combined without deformation or damage; the connecting piece is to connect the face plate and the support The structure is connected into a whole accessory.

Building formwork is a formwork and support formed by concrete pouring. According to the nature of the material, it can be divided into building formwork, building wood plywood, laminated board, multi-layer board, double-sided laminated, double-sided laminated construction template, etc. Building templates can be divided into cast-in-place concrete templates, pre-assembled templates, large templates, and jump templates according to construction process conditions.

The combined steel formwork is a new formwork with the advantages of strong versatility, convenient assembly and disassembly, and many turnover times in modern formwork technology. It can be used for the construction of cast-in-place reinforced concrete structures. According to the design requirements, the large-scale formwork of beams, columns, walls, and floor slabs is assembled and hoisted in place as a whole, and the method of bulk dismantling can also be adopted.

 

Reasons for deformation:

 

1. Assemble small steel molds, which are not set up according to regulations, resulting in poor overall performance of the building

2. The foundation on which the template is placed is not firm, the plate is not placed, and the foundation is sinking due to poor waterproof measures

3. Use wooden building formwork or plywood for construction, and the concrete is not poured in time after the experience is accepted, and the surface is deformed in the sun and rain for a long time.

4. The support spacing is too large, and the rigidity of the steel plate is poor

5. The speed of pouring wall and column concrete is too fast, the height of one-time pouring is too high, and the vibration is excessive.

 

1. When assembling the combined small steel mold, the connecting pieces should be placed according to the regulations, and the spacing and specifications of the purlin and the opposite tension bolts should be set according to the design requirements.

2. The support spacing at the bottom of the beam should be able to ensure that no deformation occurs under the action of the weight of the concrete and the construction load. If the bottom of the support is a soil foundation, it should be conscientiously compacted, set up a drainage ditch, and lay long skids or steel to ensure support Does not sink.

3. When using wooden building templates and plywood building templates, the concrete should be poured in time after the experience has passed to prevent the wooden building templates from deforming due to long-term exposure to the sun and rain.

4. In the design of building formwork and supporting system, full consideration should be given to its own weight, construction load and concrete self-sufficiency and lateral pressure generated during pouring to ensure that the building formwork and support have sufficient bearing capacity, rigidity and stability.

5. For cast-in-place reinforced concrete beams and slabs with a span of not less than 4m, the building formwork should be arched according to the design requirements; when the design has no specific requirements, the arching height should be 1/1000-3/1000 of the span.


Post time: Nov-10-2021