What Causes Failures In Concrete Formwork?
Numerous factors lead to the failure of formwork either during or after the concrete placement. The improper placing of concrete can cause the failure of formwork because the weight of concrete cannot be supported by your formwork system. Moreover, there is another factor that can lead to the failure of formwork. Omissions in the assembly detail is another component that can lead to the failure of formwork.
Localized weakness and overstress can occur that destabilizes the formwork system. Also, errors in workmanship due to indifference, haste, or lack of knowledge is another cause that can lead to failure. Concrete formwork failures can result in damage to life, increase the construction cost, and can also cause a delay in construction. Hence, it is crucial to familiarize with the reasons for failure and consider strategies that enable proper prevention.
● Inadequate Stripping and Shore Removal - When forms are stripped early or if careless practices are undertaken in reshoring, it causes failure in formwork. And when failures occur in multi-storey buildings, its collapse likely occurs. Premature stripping can cause sagging of concrete which is partially cured. This further leads to the development of cracks and creates maintenance issues. It may lead to the collapse of the entire formwork or damage to the concrete structure.
● Insufficient Bracing - One of the most common causes of formwork failure include inadequate cross and horizontal bracing. This is usually because the lateral force is created by poor bracing and therefore, causes lateral deformation of other supporting members. A failure can occur at one point, but insufficient bracing may result in expanding it into larger portions causing more damage.
● Inadequate development of concrete strength - This is another factor which is reported to be the cause of failure in concrete formwork systems. For instance, one of the greatest examples of such failure, it is the failure of a hyperbolic cooling tower in Ohio. It collapsed because of inadequate strength development. After forms are raised and the additional level is cast, the concrete placed the previous day can fail at the anchors.
● Impact and Vibration - Impact of the passing traffic and its vibration, movement of the workers working and equipment on formwork, may cause displacement in concrete consolidation. It can also cause total failure of the forms.
● When it is not the fault of formwork - There are instances where the formwork is not at fault and the failure of the formwork system is not associated with formwork faults. In such cases, other components are believed to be the cause of failure. It includes inadequate shear reinforcement placement, the ducts are placed at high-stress regions in Slabs, etc. Consider Leeds Reinforced Steel Contractors who will not make such a mistake and ensure that the formwork doesn't fail.
Summary
There are several different kinds of formwork in practice, and it depends on the construction that helps in deciding whether the designs are robust or not. Formworks are permanent or similar moulds in which concrete or other similar material is poured to give it an adequate shape.
