What is used to support reinforcing steel bars at the desired height?

Bolsters and chairs are specifically designed to support reinforcing steel bars, commonly referred to as rebar, at the specified height above the concrete substrate. This is crucial during the concrete pouring process to ensure that the rebar is properly placed within the concrete to achieve optimal structural integrity and strength. These support tools allow the rebar to be positioned correctly, maintaining the necessary cover and spacing as dictated by design specifications and industry standards.

Forms are temporary structures used to shape the concrete, but they do not provide support for the rebar itself. Braces are generally used to stabilize forms or structures but are not specifically designed for rebar support. While the term ‘supports’ can be broad and might imply structural aid, it lacks the specificity of bolsters and chairs that are uniquely intended for rebar placement. Thus, bolsters and chairs are the correct choice for maintaining the desired height of reinforcing steel bars during concrete construction.