Joints are 'Planned Break' in concrete which allow RCC to move and prevent random cracking.
TYPES OF JOINTS
- Provided where the construction work stops temporarily.
- Tie bar are provided for good bonding.
- Should not be provided at corner(high shear force) and middle(high bending moment).
- Provided at 2/3 part of the span.
- 3m<construction joint<18m</li>
2.EXPANSION JOINT/ISOLATION JOINT
- This joint is provided in builidings larger than 45m.
- C/C spacing of joints.
- Wall,frame structure~30m
- Open slab ~ 15m
- Parapet/Coping ~ 6-12m
- Dowel bars,Joint filler,Joint sealer are used to connect slab.
3. CONTRACTION JOINT/CONTROL JOINT
- It is a joint that is put in the concrete to control cracking.
- Maximum joints at 4.5 metre in unreinforced slab.
- In roof,wall and floor 5-10m spacing between shrinkage joints.