Recommended Practice for Open-Graded Premix Carpet (Third Revision)

The Introduction of IRC 14 outlines the scope and materials specifications for Open Graded Premix Carpet and Seal Coat. Key specifications for coarse aggregates used in premix carpet are given in Table 1, which includes properties such as abrasion value (max 40%), flakiness index (max 25%), stripping value (max 10%), water absorption (max 2%), soundness loss (max 12% for slag), bulk density (min 1120 kg/m3 for slag), and polish stone value (min 55). Quantities of aggregates required are detailed in Tables 2 and 3 (not fully provided here). These ensure durability and performance of the pavement surface as per the standards. The Introduction also references construction procedures and opening to traffic guidelines in later clauses.

Sources: TABLE 1. PROPERTIES OF COARSE AGGREGATES, Clause 3.2.1

Key material specifications for coarse aggregates as per IRC 14 are summarized in Table 1 below. Important properties include abrasion value (max 40% or 30%), flakiness index (max 25%), stripping value (max 10%), water absorption (max 2%), soundness loss for slag (max 12%), bulk density for slag (min 1120 kg/m3), and polish stone value (min 55). These properties ensure durability and performance of aggregates in road construction. The relevant test methods are IS:2386 (various parts), IS:6241, and BS:812 (Part-114). Quantities of aggregates for premix carpet and seal coat are provided in Tables 2 and 3 (not shown here).

Sources: TABLE 1. PROPERTIES OF COARSE AGGREGATES

IRC 14 specifies a 20 mm thick open graded premix carpet using paving grade bitumen or modified bitumen as a wearing course binder. The binder type and grade are selected by the Engineer-in-Charge based on climatic, traffic, and terrain conditions (Clause 3). The document covers materials, quantities, construction procedures, and opening to traffic guidelines. It also includes specifications for seal coats: Type A (liquid seal coat) and Type B (premixed seal coat). Key points include:

• Thickness: 20 mm
• Binder: Paving grade bitumen or modified bitumen
• Binder selection: Engineer's discretion per site conditions
• Seal coats: Type A and Type B

Unfortunately, specific formulas or detailed tables for mix design or quantities are not provided in the retrieved context. For detailed mix proportions and construction steps, refer to Clauses 3.1 to 3.4 in IRC 14.

Sources: Clause 3, Clause 3.1, Clause 3.2, Clause 3.3, Clause 3.4

For construction as per IRC 14, key specifications and properties for coarse aggregates are given in Table 1. Important parameters include:

• Abrasion value (Los Angeles machine or Aggregate Impact Value): Max 40% (30% for some cases) per IS:2386 (Part IV)
• Flakiness index: Max 25% per IS:2386 (Part I)
• Stripping value: Max 10% per IS:6241
• Water absorption: Max 2% per IS:2386 (Part III)
• Soundness (loss with sodium sulphate, 5 cycles, for slag only): Max 12% per IS:2386 (Part V)
• Bulk density (slag only): Min 1120 kg/m3 per IS:2386 (Part III)
• Polish stone value: Min 55 per BS:812 (Part-114)

These properties ensure quality of aggregates used in premix carpet and seal coat construction as referenced in Clauses 3.2.1 and 4.3. Construction procedures are outlined in Clause 3.3.

Sources: Clause 3.2.1, Clause 4.3, Clause 3.3, Table 3.1

As per IRC 14 Clause 3.3.1, weather and seasonal limitations for laying bituminous mix specify that the work shall not be carried out during rain, fog, dust storms, or when the air temperature at the surface is below 10°C or wind speed exceeds 40 km/h. This ensures proper curing and bonding of the bituminous layers.

Key temperature ranges for manufacturing and laying bituminous mixes (Clause 3.3.4 and Table 7) are:

*Exact temperatures depend on modifier type and supplier advice.

These limits ensure proper mixing, laying, and compaction of bituminous materials under suitable weather conditions to achieve durability and performance.

Sources: Clause 3.3.1, Clause 3.3.4, Table 7

As per IRC 14 Clause 3.3.2, the preparation of surface for bituminous surfacing requires the underlying surface to be free from dust, caked mud, and loose extraneous matter, shaped to the specified profile. Irregularities like potholes or ruts must be corrected with premixed chippings or coated macadam after applying a tack coat and proper compaction. Cleaning is done by wire brushing, mechanical sweeping, and dusting with air jet or washing as approved. For granular surfaces, a prime coat is applied as per IRC:15. Tack coat application rates are given in Table 4, e.g., 2.5 to 3.5 kg per 10 m² on granular surfaces and 2.0 to 3.0 kg on existing blacktop surfaces. The temperature ranges for mixing, laying, and rolling bitumen mixes are specified in Table 7, ensuring proper coating and compaction. The surface preparation ensures a clean, stable base for subsequent bituminous layers.

Sources: Clause 3.3.2, Table 4, Table 7

The preparation of binder as per IRC 14 includes the following key points:

• Before use, cationic bitumen emulsion drums shall be rolled slowly to and fro at least 5 times over about 10 meters to evenly distribute any sedimentation (Clause 4.3.3).

• Premixing of cationic bitumen emulsion with aggregates is done in suitable mixers like cold mixing plants or concrete mixers. For large works, continuous mixing in batch or continuous cold mix plants is specified (Clause 4.3.4).

• Quantities of binder required for various applications per 10 m² of road surface are given in these tables:

These quantities vary slightly by clause and type of seal coat (Tables 4, 5, 6).

• Fine aggregates used have a fineness modulus > 2.5 or pass IS Sieve 2.36 mm and retained on 180 microns (Clause 2.36).

This ensures proper binder distribution and mix quality for road surface treatments.

Sources: Clause 2.36, Clause 3.2.2, Clause 4.3.3, Clause 4.3.4, Clause 11.2, Clause 14.6

For preparation of premix carpet as per IRC 14, key specifications and formulas include:

• Aggregate Quantities (Clause 3.2.1 & 13.2):

  • Use 0.135 cum of aggregates per batch (0.09 cum of 13.2 mm size + 0.045 cum of 11.2 mm size) to cover 5 sqm with 20 mm thickness.
  • Mixing sequence in concrete mixer: first 13.2 mm aggregate, then 4.5-5.5 kg cationic bitumen emulsion, followed by 11.2 mm aggregate and remaining emulsion.
  • Mixing time should not exceed 2 minutes.
  • Manual mixing: 0.06 cum aggregates per heap, damp aggregates preferred.

• Spreading and Rolling (Clause 4.3.5):

  • Spread premix within 10 minutes of tack coat application.
  • Uniform thickness and cross fall ensured by camber boards.
  • Rolling immediately after laying using 8-10 tonne smooth wheeled tandem roller.

• Seal Coat Application (Clause 4.3.6):

  • Apply seal coat 4-6 hours after laying premix.
  • For Type A seal coat, spread clean stone chips uniformly after emulsion spray.

• Binder Quantities for Tack Coat (Table 4):

These guidelines ensure proper premix carpet preparation and application as per IRC 14.

Sources: Clause 3.2.1, Clause 13.2, Clause 4.3.5, Clause 4.3.6, Table 4

Key specifications for spreading and rolling of premix per IRC 14 are:

• Spreading: Premixed material shall be spread within 10 minutes of applying the tack coat, uniformly to the desired thickness, grade, and cross fall (camber). Camber is checked by camber boards; avoid excessive raking. (Clause 4.3.5)

• Rolling: Rolling starts immediately after laying using an 8-10 tonne smooth wheeled tandem roller unless otherwise approved. Rolling proceeds from edges to center longitudinally, covering at least 1/3 width of the previous pass. Avoid excessive rolling and use minimal water to prevent mix pickup. Rolling must finish before mix temperature drops below limits in Table 7. (Clause 4.3.5, 3.3.6)

• Mixing quantities: For 5 sqm area with 20 mm thickness, use 0.135 cum aggregate (0.09 cum 13.2 mm + 0.045 cum 11.2 mm) with 4.5-5.5 kg cationic bitumen emulsion per batch. (Clause 13.2)

• Temperature ranges for mixing and rolling (Table 7):

*Exact temperatures depend on modifier type and supplier advice. (Clause 3.3.4, Table 7)

This ensures uniform coating, proper compaction, and durability of the premix carpet.

Sources: Clause 13.2, Clause 4.3.5, Clause 3.3.6, Clause 3.3.4, Table 7

The application of seal coat as per IRC 14 involves specific quantities of binder and preparation steps. For 11.2 mm size aggregate, the quantity of binder per 10 m² area is given in two tables:

Another source in Clause 14.6 specifies:

Key construction points include:

• Weather and seasonal limitations as per Clause 3.3.1.
• Surface preparation as per Clause 3.3.2.
• Binder preparation: Roll cationic bitumen emulsion drums slowly at least 5 times over 10 m before use.
• Premix preparation: Use suitable mixers like cold mixing plants or concrete mixers; continuous mixing for large works.

These specifications ensure proper binder quantity and preparation for effective seal coat application.

Sources: Clause 11.2, Clause 14.6, Clause 3.3.1, Clause 3.3.2

Key quality control and testing specifications for coarse aggregates per IRC 14 include the following properties and their limits:

For binders in tack coats, the quantity per 10 m2 of road surface is:

• On granular (primed) surface: 2.5 to 3.5 kg
• On existing black top surface: 2.0 to 3.0 kg

These parameters ensure material quality and proper application rates for premix carpet and seal coat layers, critical for durability and performance. Test methods are standardized as per IS codes referenced above.

Sources: TABLE 1. PROPERTIES OF COARSE AGGREGATES, TABLE 4. QUANTITY OF BINDERS FOR TACK COAT

For IRC 14, the quantities of materials required for premix carpet and seal coat are specified in Tables 2 and 3 respectively, as per Clause 3.2.1. These tables provide the exact aggregate quantities needed. Additionally, Clause 4.2 and 3.2 emphasize the importance of accurate material quantity estimation for mix proportions. While the exact tables are not reproduced here, they typically list aggregate quantities per unit area or volume for different mix types. For precise mix proportions, refer directly to these tables in IRC 14. Generally, mix proportions depend on the type of bituminous mix and aggregate grading, ensuring durability and performance.

Sources: Clause 3.2.1, Clause 4.2, Clause 3.2

The IRC 14 code provides key specifications and tables relevant to equipment and machinery materials, particularly focusing on aggregates and binders used in road construction. For coarse aggregates, important properties and their limits are given in Table 1, including abrasion value (max 40%), flakiness index (max 25%), stripping value (max 10%), water absorption (max 2%), soundness loss (max 12% for slag), bulk density (min 1120 kg/m3 for slag), and polish stone value (min 55). For binders used in tack coats, Table 4 specifies quantities per 10 m²: 2.5 to 3.5 kg on granular surfaces and 2.0 to 3.0 kg on existing blacktop surfaces. These tables and specifications ensure proper material quality and quantity for equipment and machinery operations in road works as per IRC 14.

Sources: TABLE 1. PROPERTIES OF COARSE AGGREGATES, TABLE 4. QUANTITY OF BINDERS FOR TACK COAT

The retrieved context from IRC 14 does not explicitly provide formulas, tables, or detailed specifications specifically for Safety and Handling. However, general good practice for Safety and Handling in highway construction includes proper use of personal protective equipment (PPE), safe storage and handling of bitumen and aggregates, and adherence to traffic management during construction and opening to traffic as outlined in Clauses 3.3 and 3.4. For material quantities, Table 6 (Clause 14.6) specifies binder quantities for seal coats: 9.8 kg per 10 m² for Type "A" liquid seal coat and 6.8 kg per 10 m² for Type "B" premixed seal coat. For comprehensive safety procedures, refer to the relevant sections on construction and opening to traffic (Clauses 3.3 and 3.4) and standards like BS:812 (Part-114) mentioned for testing. No direct safety formulas or handling tables are provided in the retrieved text.

Sources: Clause 14.6, Clauses 3.3, 3.4, BS:812 (Part-114)

The key references and standards in IRC 14 include specifications for materials and testing methods for highway bituminous surfacing. For example, Table 1 lists properties of coarse aggregates with their specifications and test methods, such as:

• Abrasion value: Max 40% (Los Angeles machine) or Max 30% (Aggregate Impact Value) per IS:2386 (Part IV)
• Flakiness index: Max 25% per IS:2386 (Part I)
• Stripping value: Max 10% per IS:6241
• Water absorption: Max 2% per IS:2386 (Part III)
• Soundness (slag only): Max 12% loss with sodium sulphate (5 cycles) per IS:2386 (Part V)
• Bulk density (slag only): Min 1120 kg/m3 per IS:2386 (Part III)
• Polish stone value: Min 55 per BS:812 (Part-114)

Quantities of aggregates for premix carpet and seal coat are given in Tables 2 and 3 respectively (not shown here). These standards ensure quality and durability of highway surfacing materials.

Sources: TABLE 1, Clause 3.2.1