Standards of Reinforcements Detailing in Slabs and Beams
Reinforcement Detailing in Slabs and Beams performs a vital role in a construction process to provide durability and strength to the structure. It also helps out in the cost optimization for the project. A structure?s cover to reinforcement, length of the reinforcement, it?s curtailment, number and diameter should all be clearly defined by the detailing of the reinforcement of the concrete beams and slabs.
Consider a generic concrete slab or beam, supported via simple means. This structure would experience the maximum bending moment at the center of the span. The shear force will come at a distance of d/2 from the face of the support (where d = effective depth of the slab or the beam).
This indicates clearly that the bending reinforcement is required at the center of the span, where the bending moment occurs, not at the support. Whereas the support should be reinforced to withhold the shearing forces.
Therefore, it would not be necessary to cover the full length of the structure in tension reinforcement. In fact, as much as 50% of the reinforcement can be curtailed at suitable locations. They can also be repurposed as shear reinforcements by bending them upwords.
1. Reinforcement Details of Simply Supported Beam and Slab
For a simply supported slab or beam, 100% of reinforcement is given at the mid span of the structure to act as the tension reinforcement. Whereas, 50% of the reinforcement is curtailed at a distance from the center support for the searing forces.
2. Reinforcement Details of Continuous Beams and Slabs
For continuous beams and slabs, you need to draw up the plans to indicate the shear force and bending moment. Then you can detail the reinforcement depending upon those values. The tension reinforcements go 100% at the center of the span, and the shear reinforcements are attached to the end support piece intermediately.
3. Typical reinforcement detail for concrete beam
A typical reinforcement detail for a concrete beam must indicate the diameter of the reinforcements, how many of them there are necessary, and the length of the reinforcements at both the top piece and the bottom piece.