QA/QC  › Roads & Pavement  › Sub-base & Base
Checklist · QC-ROD-CHK-002
Sub-base & Base Course Checklist
25 checkpoints across 6 sections. For all WBM, WMM, GSB courses; critical before bituminous layer placement
25 Checkpoints
6 Sections
Per course placement cycle; continuous throughout construction
QC Engineer, Site Engineer

Checklist Preview

S.No.CheckpointIS RequirementStatus
A. AGGREGATE MATERIAL QUALITY
A1Aggregate source approved; quarry documentation and test certificates available
Acceptance: Source test report dated <12 months; all test parameters within spec
Cl. 401 — Material approval
OK
NC
NA
HOLD
A2Coarse aggregate Los Angeles Abrasion (LAA) value ≤ 40%
Acceptance: LAA ≤ 40% for WBM/WMM; tested per IS 2386 Part IV; 1 test per 1000 tonnes
Cl. 401 — Durability requirement
OK
NC
NA
HOLD
A3Impact value of coarse aggregate ≤ 30% (for WBM)
Acceptance: Impact value ≤ 30% for WBM; measured per IS 2386 Part IV
Cl. 401 — Strength requirement
OK
NC
NA
HOLD
A4Aggregate grading complies with specification (sieve analysis results)
Acceptance: Sieve analysis within ±5% of spec limits for each sieve; 1 test per 500 tonnes
Cl. 401 — Grading compliance
OK
NC
NA
HOLD
A5Fines material (<75 micron) ≤ 10% for WBM/WMM; PI of fines 4-9
Acceptance: Fines ≤ 10% by dry weight; PI 4-9 (determined per IS 2720); non-plastic fines acceptable
Cl. 401 — Fines control
OK
NC
NA
HOLD
A6Elongated & flaky aggregate particles ≤ 25% (for WBM)
Acceptance: E&F ≤ 25%; measured per IS 2386 Part I; manual sieving method
Cl. 401 — Shape control
OK
NC
NA
HOLD
B. MATERIAL DELIVERY & STOCKPILING
B1Aggregate delivered per approved material schedule; source batch identity maintained
Acceptance: Delivery note includes source, date, test cert; segregation by lot maintained
Cl. 401 — Material traceability
OK
NC
NA
HOLD
B2Stockpiles separated by size fraction; no intermingling of material
Acceptance: Clear separation between coarse & fines stockpiles; covered to prevent contamination
Cl. 401 — Segregation control
OK
NC
NA
HOLD
B3Stockpile surface compacted and protected from surface water infiltration
Acceptance: No pooled water; top layer compacted; covered during heavy rain
Cl. 401 — Moisture control
OK
NC
NA
HOLD
B4Material moisture content ≤ 2% above OMC at time of placement
Acceptance: Measured moisture ≤ (OMC + 2%); tested daily or before compaction
Cl. 401 — Moisture at placement
OK
NC
NA
HOLD
C. LAYING & SPREADING
C1Subgrade inspected and approved before course material is spread
Acceptance: Subgrade approval sign-off available; surface cleaned of debris
Cl. 401 — Prerequisite approval
OK
NC
NA
HOLD
C2Material spread uniformly in single layer of specified thickness (150-200mm)
Acceptance: Layer thickness: 150-200mm ±10mm; measured at 50m intervals; 4-5 cross-sections per km
Cl. 401 — Thickness control
OK
NC
NA
HOLD
C3Spreader equipment maintains uniform depth across full width; roller behind spreader
Acceptance: Spreader hopper empty before reversing; no segregation visible at edges
Cl. 401 — Equipment efficiency
OK
NC
NA
HOLD
C4Material bond breaker (dry stone dust or sand) applied if required for WMM/GSB
Acceptance: Sand/dust layer 3-5mm; uniform distribution; prevents bonding to subgrade
Cl. 401 — Interface treatment
OK
NC
NA
HOLD
Showing 14 of 25 checkpoints ·
A. AGGREGATE MATERIAL QUALITY
A1Aggregate source approved; quarry documentation and test certificates available
Cl. 401 — Material approval (SP 20)
Source test report dated <12 months; all test parameters within spec
OKNCNAHOLD
A2Coarse aggregate Los Angeles Abrasion (LAA) value ≤ 40%
Cl. 401 — Durability requirement (IS 2386)
LAA ≤ 40% for WBM/WMM; tested per IS 2386 Part IV; 1 test per 1000 tonnes
OKNCNAHOLD
A3Impact value of coarse aggregate ≤ 30% (for WBM)
Cl. 401 — Strength requirement (IS 2386)
Impact value ≤ 30% for WBM; measured per IS 2386 Part IV
OKNCNAHOLD
A4Aggregate grading complies with specification (sieve analysis results)
Cl. 401 — Grading compliance (IS 2386)
Sieve analysis within ±5% of spec limits for each sieve; 1 test per 500 tonnes
OKNCNAHOLD
A5Fines material (<75 micron) ≤ 10% for WBM/WMM; PI of fines 4-9
Cl. 401 — Fines control (IS 2386)
Fines ≤ 10% by dry weight; PI 4-9 (determined per IS 2720); non-plastic fines acceptable
OKNCNAHOLD
A6Elongated & flaky aggregate particles ≤ 25% (for WBM)
Cl. 401 — Shape control (IS 2386)
E&F ≤ 25%; measured per IS 2386 Part I; manual sieving method
OKNCNAHOLD
B. MATERIAL DELIVERY & STOCKPILING
B1Aggregate delivered per approved material schedule; source batch identity maintained
Cl. 401 — Material traceability (SP 20)
Delivery note includes source, date, test cert; segregation by lot maintained
OKNCNAHOLD
B2Stockpiles separated by size fraction; no intermingling of material
Cl. 401 — Segregation control (SP 20)
Clear separation between coarse & fines stockpiles; covered to prevent contamination
OKNCNAHOLD
B3Stockpile surface compacted and protected from surface water infiltration
Cl. 401 — Moisture control (SP 20)
No pooled water; top layer compacted; covered during heavy rain
OKNCNAHOLD
B4Material moisture content ≤ 2% above OMC at time of placement
Cl. 401 — Moisture at placement (IS 2720)
Measured moisture ≤ (OMC + 2%); tested daily or before compaction
OKNCNAHOLD
C. LAYING & SPREADING
C1Subgrade inspected and approved before course material is spread
Cl. 401 — Prerequisite approval (SP 20)
Subgrade approval sign-off available; surface cleaned of debris
OKNCNAHOLD
C2Material spread uniformly in single layer of specified thickness (150-200mm)
Cl. 401 — Thickness control (SP 20)
Layer thickness: 150-200mm ±10mm; measured at 50m intervals; 4-5 cross-sections per km
OKNCNAHOLD
C3Spreader equipment maintains uniform depth across full width; roller behind spreader
Cl. 401 — Equipment efficiency (SP 20)
Spreader hopper empty before reversing; no segregation visible at edges
OKNCNAHOLD
C4Material bond breaker (dry stone dust or sand) applied if required for WMM/GSB
Cl. 401 — Interface treatment (SP 20)
Sand/dust layer 3-5mm; uniform distribution; prevents bonding to subgrade
OKNCNAHOLD
Showing 14 of 25 ·
Inspection Sign-Off
APPROVED
APPROVED WITH CONDITIONS
REJECTED — NCR RAISED
Remarks
Name / Sign / Date
Inspected By
Name / Sign / Date
Reviewed By
Name / Sign / Date