What is the primary role of bar supports in construction?

The primary role of bar supports in construction is to align and support rebar effectively. Bar supports are essential components in concrete construction as they ensure that the rebar is positioned at the correct height and orientation within the concrete form. This positioning is crucial for the strength and integrity of the reinforced concrete structure.

By keeping the rebar in place, bar supports help ensure proper concrete coverage over the rebar, which is vital for protecting the steel from corrosion and ensuring optimal bonding between the concrete and the rebar. Proper alignment and support also assist in preventing displacement of the rebar during the pouring of concrete, leading to a structurally sound final product.

While other options mention aspects related to concrete, they do not pertain to the specific function of bar supports. For instance, decoration is not a purpose of bar supports, nor do they serve to insulate or directly increase the tensile strength of concrete—these aspects are covered by the properties of the concrete mix and the rebar itself.