Formwork is a temporary mold used to shape wet concrete or other materials while they set. It must be strong enough to bear the weight of the concrete and other loads. It should also be rigid to prevent it from collapsing under the load and causing injury or damage to the structure. The Occupational Safety and Health Administration (OSHA) sets standards for formwork construction.
For example, when working with formwork, OSHA recommends that workers be protected by guardrails and other barriers to avoid falling or getting crushed. The OSHA standards also require that the work be done by trained, competent individuals. If not, the risk of injuries and deaths is high.
When formwork is properly constructed and installed, it can greatly reduce the time required for placing concrete and other materials in a given area and reduce construction costs. Formwork is also vital to ensuring that the concrete or other material is made in the correct shape and dimensions for the specific application. In addition, it can help minimize the amount of rework and wasted concrete.
Formwork should be built using a strong, lightweight material. It should be rigidly constructed and efficiently propped and braced both horizontally and vertically to retain its shape. The joints should be tight to prevent leakage of cement grout. The formwork should also be designed to allow removal of various parts in a desired sequence without damaging the concrete.
Several different kinds of formwork are available for different applications. Wooden formwork can be made from timber or plywood, and metal formwork can be made from aluminium or steel. Typically, wooden formwork is cheaper and can be reused for multiple pours. However, it requires frequent maintenance and repair. Metal formwork, on the other hand, is more expensive but can be reusable for up to two thousand pours. It is also more durable than wooden formwork and can resist moisture and chemicals better.
Prefabricated formwork systems are used to minimize the construction time and costs on site. These are assembled offsite and then brought to the construction site. They can be transported on a truck or trailer and then placed in the correct position by a crane. They are then filled with concrete on the construction site. Some of these systems are capable of handling the entire height of a building, which saves time and labor.
Plywood is a strong, durable and light-weight material that is used for forming concrete structures. It can be easily cut into required size and is available in different thicknesses. It is usually painted or treated with a chemical to avoid the transfer of moisture from concrete to the plywood. It is also a cost-effective material to use because it can be reshaped many times and is easy to recoup the initial investment.
Steel formwork is another popular option because it offers a longer life span and multiple time reuses. It is often utilized for curved structures such as tanks, columns, chimneys, tunnels and retaining walls. This type of formwork consists of modular panels that can be fixed together with Clamp, Nut and Bolts.
