B3. Edge Reinforcement at Free Edge of Slabs

Code Compliance & Reference
This detail complies with HKRC2004 Clause 9.3.1.6 regarding the reinforcement at free edge for slabs.

Comments

1. The code specifies a U-bar (with cross bars) at the free edge. For slabs without top reinforcement, having bottom reinforcements continue around the free edge can help reduce amount of steel reinforcement (due to omitting a lap).
2. The common locations for free edge of slabs include cantilever slabs and staircase (which span top to bottom). For staircase slabs, the free edge is on the transverse direction; if the code is to be followed strictly, additional cross bars will be required (since the main reinforcement will be outside the bent of transverse bars and cannot act as cross bars).