IRC 107:2013 is the Indian Standard (IRC) for specifications for bituminous concrete (bc), bc (ac) as wearing course on roads. IRC 107:2013 specifies Bituminous Concrete (BC) — the premier dense-graded wearing course for Indian flexible pavements. BC 13 (13 mm maximum aggregate) is widely used for urban arterials and moderate-traffic highways; BC 19 (19 mm) for heavier-duty corridors. IRC 107:2013 covers every aspect from aggregate source to acceptance: crushing value ≤ 30%, Marshall stability ≥ 12 kN, binder content 5.0-6.5%, field density ≥ 98% of target, and rutting resistance verification. The specification interfaces tightly with [IRC 37:2018](/code/IRC-37-2018) pavement design (where BC properties are the elastic modulus input) and [IS 73](/code/IS-73-2013) bitumen specifications. Every modern Indian NH / SH BC laying is governed by IRC 107 or the closely-aligned IRC 29:2019 (Dense Bituminous Concrete). The specification bridges the gap between laboratory research and field practice — giving engineers clear, enforceable criteria for pavement quality.
Specifies the materials, mix design, production, laying, compaction, and acceptance of Bituminous Concrete (BC), Asphalt Concrete (AC), and similar dense-graded bituminous wearing courses used on Indian roads and highways.
- Status
- Current
- Usage level
- Essential
- Domain
- Transportation — Pavement and Road Materials
- Type
- Specification
- Amendments
- Amendment No. 1 (2018) — updated rutting acceptance criteria for hot climates; Amendment No. 2 (2022) — added provisions for RAP (Reclaimed Asphalt Pavement) up to 20% content
Also on InfraLens for IRC 107
Practical Notes
! BC and DBC are closely related — both are dense-graded hot-mix. IRC 107 covers 'BC' nomenclature; IRC 29 covers 'DBC' (also called BC in some regional contexts). Practical differences are minor; specification is often chosen by state PWD preference.
! BC 13 uses 13 mm maximum aggregate size — suitable for 40-50 mm thick wearing courses. BC 19 uses 19 mm aggregate — suitable for 60 mm+ thick courses on heavy-duty corridors.
! Quality of coarse aggregate (crushing value, soundness) is the most common source of BC failures. Cheaper aggregate from substandard quarries causes early ravelling. Source approval at project start + periodic re-testing is essential.
! Marshall mix design is the Indian default, although some NH projects now use Superpave gyratory method (based on AASHTO M323). Superpave provides better rutting prediction but requires specialized equipment.
! VG-30 handles moderate Indian climates (Northern plain, most of Maharashtra, Karnataka). VG-40 for hot zones (Rajasthan, Gujarat summers). PMB-40 for heaviest-duty (Golden Quadrilateral, expressways, toll plazas).
! Polymer modification (PMB) improves rutting resistance at summer temperatures AND cracking resistance at low temperatures. 10-15% cost premium; 30-40% longer service life on heavy corridors.
! Hot-mix plant must have: accurate weighbridge, drying drum or burner, mixing drum with temperature control, storage silos with thermal insulation, automated batching controls. Drum mix plants preferred for continuous production.
! Transport time from plant to site should be ≤ 90 minutes (VG-30) or 60 minutes (PMB-40) to maintain laying temperature. Longer transport = temperature drop = compaction problems.
! Tack coat on base course: 0.2-0.3 l/m² residual bitumen emulsion. Essential for BC-to-base bonding. Missing tack coat causes BC layer delamination under traffic.
! Paver speed: 5-8 m/minute typical. Automated feeding of paver hopper prevents thermal segregation (hotter centre, cooler edges).
! Primary rolling: steel roller, 4-6 passes, speeds 2-4 km/h. Intermediate: pneumatic (rubber-tyre) roller for voids removal, 8-12 passes. Final: steel for finish, 2-3 passes.
! Joint design: longitudinal joints at lane markings (not random), cold joint vertical face or 30 mm overlap method. Cold joints are weaker than continuous laying.
! Temperature monitoring: infrared thermometer on paver hopper + every 50 m of laid pavement. If falls below 130°C, stop rolling and accept reduced density.
! Rain during BC laying: suspend immediately. Water trapped in hot mix causes steam explosions and pock-marks. Stored mix in dumper can keep for 1-2 hours if tarped.
! Field density testing by core sampling: 15 cm diameter cores every 200-500 m². Results available next day. Rejection if below 95% of target (major non-compliance); 95-98% requires rework or extension of warranty.
! For IRC 37 M-E pavement analysis: BC elastic modulus at 35°C is ~3,000-3,500 MPa (standard VG-30/40). PMB-modified BC: ~3,500-4,500 MPa. Temperature correction per IRC 37 Appendix C.
! Urban BC on signalized intersections: additional consideration for bus stop areas, traffic signal approaches, stop-go movements. Local cement-concrete patches at bus stops are common to handle concentrated loading.
! Highway BC longitudinal joint maintenance: 5-10 years after laying, joints open up from thermal cycling. Crack sealing with hot-pour sealant extends life by 3-5 years.
! Climate change impact: hotter summers mean more BC softening and rutting. VG-40 or PMB increasingly specified where VG-30 was historical default. Check 30-year climate forecasts for critical projects.
! Recycled asphalt (RAP) use: up to 20% allowed per Amendment No. 2. Reduces virgin material cost and carbon footprint. RAP quality verified per IS 15469 before mixing.