Method Statement for Concrete Kerb Construction

Scope

This method statement covers construction of cement concrete kerbs in central medians, footpaths and separators in accordance with project drawings and applicable codes. It is suitable for cast-in-situ mechanized casting and precast kerb installation where machine casting is not feasible.

References

Primary references used for specification and testing:

Materials & Mix Design

Kerbs shall be provided as per the cement concrete design drawings. Concrete mix design shall be performed and approved by the project QC laboratory to meet required strength and workability criteria, following IS 10262:2009 and MoRT&H clause 1700.

• Typical concrete grade: M20 (monolithic kerb casting possible).
• Curing: water curing or approved curing compound for minimum prescribed duration.
• Slump: maintain between 10–25 mm at site depending on transport distance and machine feed requirements.

Type of Construction & Equipment

Primary method is cast-in-situ using mechanized continuous kerb casting machine. Precast kerb blocks may be used where machine casting is impractical.

Key equipment: mechanized kerb casting machine (sensor-controlled), approved batching plant, transit mixers, auto-level with staff, winch and standard hand tools.

Preparation & Transportation

Concrete shall be batched at approved plant and transported in transit mixers. Ensure mix conformity with QC-approved design and maintain slump at arrival.

Laying Procedure (Step-by-step)

1. Set out line & level using pegs and piano wire/string at 10 m intervals (reduce to 5 m on curves).
2. Place and align the mechanized kerb casting machine over reference marks.
3. Feed concrete from transit mixer to machine; maintain slump 10–25 mm.
4. Cast kerb on WMM top (new carriageway) or on PCC (old carriageway) on a min. 40–70 mm bedding of cement concrete as specified.
5. Provide drainage recesses where footpaths or cross slopes require openings.
6. Finish and touch-up manually to achieve tolerance limits; perform joint finishing at end portions.
7. Cut expansion joints at nominal 5 m intervals when concrete attains sufficient strength; blade thickness 3–5 mm.
8. Where machine casting is not possible, use properly sized and shaped shuttering/forms for manual casting.
9. Conduct survey checks before and after casting; vertical & horizontal tolerance: ±5–6 mm as per project requirement.

Quality Control & Testing

All testing and sampling to follow MoRT&H procedures. Key checks include field density of WMM top, slump control, and compressive strength tests using cube samples (refer MoRT&H 1717.6).

Safety Measures

Implement all measures from the approved EHS plan: PPE for workers, safe handling of machinery, traffic management during kerb casting, and site housekeeping. Provide signage and speed-calming if kerb work affects live carriageway flows.