Metal reinforcement for concrete beam is made from two sliding frames one inside the other that can be adjusted to the required length

摘要

The reinforcement consists of an outer metal frame with at least two bottom bars (31) and two top bars (32), connected by a series of rectangular rings (34), and a similar inner frame with bottom (41) and top (42) bars and rings (43). The frames are able to slide relative to one another to adjust to the required length for a concrete beam being cast in situ, the outer frame having in-turned supports (351) for the inner one and stops to limit the relative movement.