Final answer:
Steel forms are used in construction primarily to provide structural support and to minimize thermal stress due to their high strength-to-weight ratio and similar expansion properties to concrete.
Step-by-step explanation:
Steel forms are utilized in construction for several important purposes. The first purpose is to provide structural support for buildings and infrastructure. As steel has a high strength-to-weight ratio, it is able to support heavy loads without adding excessive weight to the structure itself. This makes it ideal for the skeleton of large modern buildings like skyscrapers and sports stadiums. The second key purpose is to aid in minimizing thermal stress. Steel's coefficient of linear expansion is nearly identical to that of concrete, which means that as temperatures change, both materials expand and contract at similar rates. This compatibility reduces the likelihood of cracks and structural damage over time due to temperature fluctuations.