New reusable, lightweight and economical formwork element

Description of the technology

The research group Materials and Construction Systems for Buildings (belonging to the Department of Building and Urbanism at the University of Alicante-Spain) has developed a reusable formwork element to implement joints with continuous reinforcement armours in reinforced concrete construction elements. This invention is characterized through its perfect adaptation to any construction element currently available in the market, resisting the pressure exerted through the concrete. It is also a low cost element, quick and simple to use it, and it allows to obtain clean and geometric concrete joints. The group is looking for companies interested in commercial exploitation.

Specifications

This device allows easy formwork through different sections or in a continuous way, and it resists the thrusts derived from concreting. The element consists of a piece of variable height, width and thickness with periodic notches, designed to allow an optimal fitting of armours in the element to be concreted: its form of comb (see Figure 1) allows the passage of reinforcement armours between its tines. This design has been conceived to be perfectly adapted to any constructive element currently available in the market.

Main advantages of its use

• It allows to obtain clean, geometric and easily-continued joints in reinforced concrete.
• It can be removed without causing damage or abnormal jerking in concrete.
• It has a low acquisition cost, since it is a piece of simple geometry that can be manufactured with different materials.
• It is easy to be produced, since it is a small element of simple geometry that can be manufactured through companies from different sectors.
• It is not necessary any additional equipment (cranes) for handling.
• It is possible to manufacture different sizes and shapes, so it has a great versatility to be used in any type of work and in any linear or surface constructive element of reinforced concrete (e.g. slabs, tiles, beams, walls, etc.).
• It is reusable, so total cost of the work product is reduced.
• Low cost of labour during use.
• The implementation is quick and simple, reducing execution time of the formwork.
• The material used in its manufacture is resistant to the thrusts derived from concreting.
• The size and weight of the element is reduced, so it can be used through a single operator.
• Transportation from the place of manufacture is simple, as it is a piece of small size and weight that can be stacked or rolled.

Applications

• Construction and Building Products

Current development status

The formwork element described meets the requirements of the regulations (Spanish Instruction of structural concrete EHE-08) for formwork and moulds, which requires elements to be able to resist actions during the construction process. These requirements include:

• Sealing of joints.

• Suitable resistance to pressure of fresh concrete and the effects of compaction method.

• Alignment and verticality of the formwork panels.

• Maintenance of geometry.

• Easy cleaning inside the moulds, preventing the existence of any residue.

• Maintenance of characteristics that allow specific textures in the finished concrete.

• Any material can be used whenever it does not harm the properties of concrete.

A test for practical application of the described element was performed.