The purpose of Aluminum Formwork is to maintain and contain fresh concrete until it hardens and give it the desired shape. Formwork is the essential tool in the construction of concrete structures. It must give its final shape to the concrete while respecting the execution tolerances. It must withstand the loads induced by the own weight of the concrete during its pouring and control deformations (respect for the arrows of the floors, for example). It must make it possible to carry out the operations of placing the reinforcements and vibrating the concrete. On-site, the tools used for molding concrete are formwork.
In case of vertical walls and sails, these forms called shutters have given base to the structure," which refers to concrete poured into shutters. The formwork is built in Formwork System manufacturers in India. It is designed to meet the rotation cycles defined by the method department of the company by integrating many requirements: the size of formwork, location of reinforcements, and the principle of shoring.
Column Formwork must have sufficiently rigid and stable to withstand the thrust of fresh concrete especially in the case of fluid or self-consolidating concrete. It must support construction, without deforming, including during the vibration phase, and ensure the maintenance of the concrete until it sets and hardens. A good framework must be non-absorbent, be stable to guarantee safety on the site. Be airtight to prevent leakage of laitance, in particular at the foot of the formwork and at the joints, and at the adjustment of the mannequins. These frames must be able to obtain the desired surface texture to meet architectural requirements, in particular, be "unblock able" so as not to damage the concrete when stripping. In particular, in the event of frequency reuse, the deterioration of certain types of formwork (in particular wood) is likely to modify their mechanical and dimensional characteristics as well as the final appearance of the concrete.
Note: when designing the Slab Formwork, the remolding phase must be taken into account in order to avoid rework, which is difficult to repair. The forms have openings or open angles must be released easily. The choice of formwork depends on the work, the complexity of the form to be produced and the number of its reuses. We can nevertheless identify a number of common requirements that it must meet.
Undeformability and stability
A formwork must not deform under the effect of the thrust of the concrete and during its vibration. Compliance with the dimensional tolerances of the structure depends directly on this criterion.
The design of the formwork must, therefore, endeavor to respect this and stability by considering the static pressure exerted by the concrete. In common cases 2 to 6 t / m2 is sufficient depending on the height of the concreting and the dynamic stresses resulting from the vibration. This varies according to the mode of vibration and the type of vibrators. The formwork must also be stable in comparison with the forces of wind and possible shocks.