A bent is a framework composed of several structural members that defines the cross-section of a timber frame building or supports a trestle. The term bent is probably an archaic past tense of the verb to bind, referring to the way the timbers of a bent are joined together. Compare this with the term bend for a class of knots.
Bents are the building blocks which define the overall shape and character of a structure. They do not have any sort of pre-defined configuration in the way that a Pratt truss does. Rather, bents are simply cross-sectional templates of structural members (i.e. rafters, joists, posts, pilings, etc.) which repeat on parallel planes along the length of the structure. The term bent is not restricted to any particular material. Bents may be formed of wooden piles, timber framing,[1] steel framing, or even concrete.[2]
Bents are generally pre-assembled, either at the timber framing company's shop or at the construction site. After the basic post and beam structure of the frame has been set in place, the bents are then lifted and simply dropped into place one by one by the crane. Next, the workers bring in additional members, purlins, which tie them together and give the frame a more rigid structure. This process is very safe and efficient as it allows a crew to assemble a large portion of the frame without ever stepping off the ground. This in turn, minimizes the amount of time that the crew must spend several stories in the air clambering along beams not much wider than their own feet.