| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. BITUMEN & MIX DESIGN | |||
| A1 | Bitumen grade and source approved; test certificates (penetration, softening point) available Acceptance: Grade: 60/70 or 80/100 (per spec); penetration 60-70 or 80-100 dmm; test cert <6 months old | Cl. 503 — Bitumen approval | OK NC NA HOLD |
| A2 | Mix design report submitted and approved; JMF (Job Mix Formula) confirmed Acceptance: JMF includes: binder %, aggregate grading, bulk density, void ratio, stability, flow; approved before production | Cl. 503 — Mix design submission | OK NC NA HOLD |
| A3 | Trial mix conducted; Marshall stability ≥1800 kg, flow 2-4mm, void ratio 3-5% Acceptance: Marshall test results: stability ≥1800 kg, flow 2-4mm, VIM 3-5%; results documented and approved | Cl. 503 — Trial mix validation | OK NC NA HOLD |
| A4 | All aggregate material complies with grading spec; size <0.1% variation from JMF Acceptance: Sieve analysis 1 test per 100 tonnes; grading within ±0.1% of JMF; LA abrasion ≤40% | Cl. 503 — Aggregate control | OK NC NA HOLD |
| B. PLANT & MIXING OPERATIONS | |||
| B1 | Batch plant calibration current; weigh balances certified within last 6 months Acceptance: Calibration certificate on site; ±2% accuracy for hot bins; ±1% for bitumen pump | Cl. 503 — Equipment control | OK NC NA HOLD |
| B2 | Aggregate bins maintained at specified temperature; hot bin temp 130-160°C (verify thermometer) Acceptance: Drum temperature: 160-170°C ±5°C; verified with IR gun or thermocouple at start and 2-hourly | Cl. 503 — Temperature control | OK NC NA HOLD |
| B3 | Bitumen heater maintains 135-150°C; verified with temperature probe at pump outlet Acceptance: Bitumen temp: 135-150°C ±3°C; checked hourly with certified thermometer; logged on chit | Cl. 503 — Bitumen temperature | OK NC NA HOLD |
| B4 | Mixing drum temperature maintained at 160-170°C; verified with laser/IR gun Acceptance: Drum temp: 160-170°C ±5°C; IR gun verified every 30 minutes during production | Cl. 503 — Mixing temperature | OK NC NA HOLD |
| B5 | Discharged mix temperature 155-165°C; checked at discharge point with thermometer Acceptance: Mix temp at discharge: 155-165°C ±3°C; recorded on each truck ticket; variation <5°C | Cl. 503 — Discharge temperature compliance | OK NC NA HOLD |
| B6 | Batch weight tolerance ±2% of target (e.g., ±20kg for 1000kg batch) Acceptance: Each batch: target weight ±2%; scale certified; documented on batch ticket | Cl. 503 — Batch weight accuracy | OK NC NA HOLD |
| C. TRANSPORT & PAVING OPERATIONS | |||
| C1 | Truck bed cleaned, dried, and light tack oil applied before loading to prevent sticking Acceptance: Tack oil <100ml per truck; clean bed; no residual mix from previous loads | Cl. 503 — Material handling | OK NC NA HOLD |
| C2 | Material transported to site within 2 hours of discharge; temp monitored <3°C drop Acceptance: Transport time: <2 hours maximum; delivery temp ≥135°C; documented on ticket | Cl. 503 — Transport time control | OK NC NA HOLD |
| C3 | Base course inspected and approved for overlay; surface clean of debris and loose material Acceptance: Base course sign-off available; tack coat applied if required; no standing water | Cl. 503 — Surface preparation gate | OK NC NA HOLD |
| C4 | Prime coat (RC-2 or MC) applied to base course if required; coverage >1.2 kg/m² Acceptance: Prime coat: uniform coverage ≥1.2 kg/m²; dark coat on base; tested per ASTM D439 | Cl. 503 — Prime coat requirement | OK NC NA HOLD |
| C5 | Material laid by approved spreader or paver within 4 minutes of arrival at site Acceptance: Paver operational <4 min from truck arrival; screed temperature 140-150°C maintained | Cl. 503 — Laying promptness | OK NC NA HOLD |
| C6 | Paver laid in uniform passes with consistent speed; transverse joints tight (<3mm gap) Acceptance: Joint gaps <3mm; paving speed uniform; no stop-start within 100m sections; visual 100% | Cl. 503 — Laying control | OK NC NA HOLD |