Handbook of Quality Control for Construction of Roads and Runways

IRC SP 11 — General Key Specifications and Equipment

1. Equipment & Materials (Clause 25.4)

• M.S. Plates: Thickness 25.4 mm (1 in), diameters: 762 mm (30 in), 660 mm (26 in), 558 mm (22 in), 457 mm (18 in), 305 mm (12 in), 228 mm (9 in), 154 mm (6 in).
• Hydraulic Jack: 20 tonnes capacity with remote control (2-3 m flexible tubing).
• Proving Ring: 25 tonnes capacity with dial gauge and calibration chart.
• Ball Bearing Plates: 25 mm thick, 100 mm diameter with center groove.
• Datum Bar: 3 m long with stand and dial gauge clamps (2 nos).

2. Standard Penetration Test Equipment

• Constant temperature bath (electrically operated, thermostatically controlled).
• Petrol gas generator (lab model or alternative heating).
• Automatic penetrometer (adjustable weights, needles per IS 1203-1958).
• Soxhlet extraction apparatus.
• Laboratory mixer (0.02 m³ capacity with heating jacket).
• Hubbard-field stability test apparatus.
• Marshall compaction apparatus (ASTM 1559-62 T compliant).
• Distant reading thermometers.

3. Concrete & Materials Testing Equipment

• Vicat needle apparatus (IS 269-1967).
• Moulds: 100×100×500 mm prisms and 150/100 mm cubes.
• Air permeability apparatus.
• High-frequency mortar cube vibrator.
• Concrete mixer (1 cu.ft capacity).
• Vibrating table (1m×1m, IS 2514-1963).
• Flakiness index, Aggregate Impact, Los Angeles abrasion apparatus (IS 2386).
• Flow table (IS 712-1973).
• Slump test equipment.
• Specific gravity apparatus (IS 2386-Part III).

4. Aggregate Gradation (Example from Table 8.3)

IRC SP 11: Pre-requisites for Quality Control

1. Need for Quality Control (Clause 1.1)

• Ensures durability, safety, and performance of road structures.
• Minimizes defects and rework.
• Maintains compliance with specifications.

2. Pre-requisites for Quality Control (Clause 1.2)

• Qualified personnel: Skilled engineers and technicians.
• Proper equipment: Calibrated testing tools.
• Standardized procedures: Following IRC and IS codes.
• Material compliance: Use of approved materials.
• Documentation: Maintaining test records and reports.

3. Types of Quality Control (Clause 1.4)

• Incoming material control
• In-process control
• Final product control

4. Training for Quality Control (Clause 1.12)

• Regular training programs on:
  • Testing methods.
  • Interpretation of results.
  • Safety and environmental norms.

Key Table: Typical QC Parameters for Road Works

flowchart LR
    A[Qualified Personnel] --> B[Proper Equipment]
    B --> C[Standard Procedures]
    C --> D[Material Compliance]
    D --> E[Documentation]
    E --> F[Effective Quality Control]

Summary: Quality control demands trained staff, calibrated equipment, adherence to standards, and systematic documentation to ensure road construction quality per IRC SP 11.

IRC SP 11 does not explicitly provide detailed clauses on Sub-base Courses. However, based on standard pavement design practices and IRC guidelines:

Key Specifications for Sub-base Courses:

• Purpose: Provides structural support, distributes loads, and prevents intrusion of fines from subgrade.
• Material: Well-graded granular material, often gravel, crushed stone, or sand-gravel mixtures.
• Thickness: Typically varies from 150 mm to 300 mm, depending on traffic and subgrade strength.
• Compaction: Minimum 95% Proctor density to ensure stability.

Typical Design Parameters:

Basic Formula for Thickness Estimation:

[ t = k \times \sqrt{W} ]

• t = sub-base thickness (mm)
• W = design wheel load (kN)
• k = empirical coefficient depending on subgrade and material

flowchart TD
    Subgrade --> Subbase[Sub-base Course]
    Subbase --> Base[Base Course]
    Base --> Surface[Surface Course]

Summary: Use well-graded granular material, compacted to 95%, with thickness 150-300 mm based on traffic and subgrade strength. Adjust thickness per design wheel load and soil conditions.

Stone Soling as per IRC SP 11

Stone soling is a traditional sub-base layer, now less favored due to poor load distribution and sinking risks on weak subgrades.

Key Specifications:

• Material Quality: Stones must be hard, durable, and free from soft, flaky, or weathered pieces.
• Size: Generally, stone soling uses stones 40 to 75 mm nominal size.
• Thickness: Typically, the stone soling layer thickness ranges from 100 to 150 mm.
• Compaction: Proper compaction is essential to minimize settlement.
• Suitability: Avoid on soft or slushy subgrades to prevent sinking.

Quality Control:

• Stones should be tested for:
  • Aggregate crushing value (ACV)
  • Flakiness index
  • Water absorption
• Ensure uniform grading and cleanliness.

General Practice:

flowchart LR
    Quarry --> Material_Check[Material Quality Check]
    Material_Check --> Stone_Sizing[Stone Size 40-75mm]
    Stone_Sizing --> Layering[Layer Thickness 100-150mm]
    Layering --> Compaction[Proper Compaction]
    Compaction --> Subgrade[Placed on Suitable Subgrade]

Note: Stone soling is largely replaced by granular sub-base or WBM layers for better performance.

Key Specifications & Formulas for Bituminous Surface Courses (IRC SP 11):

1. Thin Bituminous Premix Carpet (Clause 5.4)

• Mix Types: Open graded or closely graded.
• Binder Content: Controlled within ±2% of specified quantity.
• Tack Coat: Applied uniformly at specified rate before premix.
• Mixing: Preferably mechanical; aggregates heated when using straight-run bitumen.
• Rolling: Immediately after spreading; roller wheels kept moist (no fuel oil).
• Seal Coat: Applied if open graded mix; follows Surface Dressing guidelines (Clause 5.2).
• Traffic: Allowed after cooling (straight-run bitumen) or after curing (cut-back bitumen).

2. Quality Control Tests & Frequency (Table 5.2)

3. Asphaltic Concrete Surfacing (Clause 5.5)

• Follow IRC 29-1968.
• Binder temperature at mixing: 150–177°C; aggregates: 155–163°C; temperature difference ≤ 14°C.
• Binder content variation allowed: ±0.3% by weight of mix.
• Mixing time: minimum for uniform coating.
• Spreading: Mechanical pavers with screeds.
• Compaction: As per specification to achieve required thickness.

4. Aggregate Gradation (Example

Compaction Characteristics of Earthwork (IRC SP 11)

Key Tests & Frequencies

Important Notes:

• Standard Proctor Test defines Optimum Moisture Content (OMC) and Maximum Dry Density (MDD).
• Dry density achieved in the field should be ≥ 95% of MDD for embankments.
• Moisture content during compaction should be within ±2% of OMC for effective compaction.

Typical Compaction Control Workflow:

flowchart TD
    A[Borrow Material Sampling] --> B[Laboratory Tests]
    B --> C{Tests}
    C -->|Gradation, Plasticity, Proctor| D[Determine OMC & MDD]
    C -->|CBR| E[Strength Assessment]
    D --> F[Field Compaction]
    F --> G[Moisture Content Check]
    F --> H[Dry Density Check]
    G --> I{Within ±2% OMC?}
    I -->|Yes| H
    I

IRC SP 11: Control Tests on Borrow Material

Key Tests & Frequency (Table 2.1)

Important Specifications

• Compaction Control: Use Standard Proctor Test for optimum moisture and maximum dry density.
• CBR Test: Critical for assessing strength of borrow material.
• Deleterious Content: Check for harmful materials affecting durability.
• Moisture Content: Frequent checks ensure proper compaction.

Sample Quality Control Records

• Maintain records in serially numbered registers.
• Link test records with payment bills to ensure quality compliance.

Summary Table for Borrow Material Properties

flowchart TD
    A[Borrow

Statistical Approach to Quality Control (IRC SP 11)

Key Formulas:

• Control Limits for Aggregate Gradation:

  [ \text{L.C.L.} = x - r \times j ] [ \text{U.C.L.} = x + r \times j ]

  where:

  • (x) = mean value
  • (j) = standard deviation
  • (r) = tolerance factor (e.g., 1.28 for 1 in 10 tolerance level)

• Standard Deviation (j):

  [ j = \sqrt{\frac{\sum (x - \bar{x})^2}{n-1}} ]

• Coefficient of Variation (i):

  [ i = \frac{j}{\bar{x}} \times 100 ]

Tables and Values:

Procedure Summary:

1. Collect test data (e.g., compressive strength or aggregate gradation).
2. Calculate mean (x) and standard deviation (j).
3. Determine tolerance factor (r) based on confidence level.
4. Compute control limits (LCL, UCL).
5. Plot progress/control charts to monitor quality (see Fig. 6 in IRC SP 11).

flowchart TD
    A[Collect Test Data] --> B[Calculate Mean (x) and Std Dev (j)]
    B --> C[Select Tolerance Factor (r)]
    C --> D[Compute LCL = x - rj and UCL = x + rj]
    D --> E[Plot Quality Control Progress Chart]
    E --> F{Within Control Limits?}
    F -- Yes --> G[Process is in Control]
    F -- No --> H[Investigate and Correct Process]

**

IRC SP 11: Testing Facilities and Equipment Summary

Key Equipment & Specifications

IRC SP 11: Sample Forms for Quality Tests – Key Points

Sample Proforma for Quality Tests (Q/R Series)

• Q/R/1: Characteristics of Borrow Materials
• Q/R/2: Compaction Characteristics of Earth Work/Gravel/Stabilized Layers
• Q/R/3: Characteristics of Aggregate/Binding Material/Screening for WBM
• Q/R/4: Characteristics of Bricks for Sub-base/Base Courses
• Q/R/5: Aggregate Characteristics for Bituminous Courses
• Q/R/6: Rate of Spread of Binder, Aggregate & Bitumen Content for Bituminous Work
• Q/R/7: Temperature Record for Bituminous Work
• Q/R/8: Surface Evenness Record
• Q/R/9: Coarse Aggregate for Concrete
• Q/R/10: Fine Aggregates for Concrete
• Q/R/11: Water for Bridge Construction Works
• Q/R/12: Cement Concrete

Key Specifications & Tables

• Aggregate Grading Control Chart: Use sieve analysis data with Upper Control Limit (UCL) and Lower Control Limit (LCL) for quality control.
• Proctor Density & CBR values: Recorded for borrow materials to ensure compaction and strength.
• Frequency of Tests: As per Table 3.1 (e.g., Aggregate Impact Value: 1 test/200 m³; Plasticity Index: 1 test/25 m²).
• Quality Control Records: Maintain serially numbered registers, linked with payment bills every third running bill.

Example: Aggregate Grading Statistical Control (Excerpt)

Functions of Quality Control Divisions (IRC SP 11)

While IRC SP 11 does not provide explicit formulas, it emphasizes a statistical approach and organizational setup for quality control (QC) in road works.

Key Functions of QC Divisions:

• Material Testing: Ensure compliance with specifications using statistical sampling.
• Process Monitoring: Continuous inspection during construction to maintain quality.
• Documentation & Reporting: Maintain records of tests and inspections.
• Corrective Actions: Identify defects and implement remedies.
• Training & Awareness: Educate staff on quality standards and procedures.

Typical QC Organizational Setup (Organizational Chart):

• Chief Quality Control Engineer
  • Material Testing Lab
  • Field Inspection Team
  • Documentation & Data Analysis Unit
  • Training & Compliance Officers

Statistical Approach (Conceptual):

• Use sampling plans and control charts (e.g., X-bar, R charts) to monitor quality.
• Apply acceptance criteria based on statistical confidence levels.

graph TD
    A[Chief QC Engineer]
    A --> B[Material Testing Lab]
    A --> C[Field Inspection Team]
    A --> D[Documentation & Analysis]
    A --> E[Training & Compliance]

For detailed sampling and acceptance criteria, refer to IS 2500 series or IRC guidelines on materials testing.

IRC SP 11: Rectification of Surface Irregularities

Key Points on Surface Regularity Check (Clause 3.2.5 & 6)

• Equipment:

  • Straight-edge (length = 1.5 m)
  • Two graduated wedges
  • Team: 2 workmen (operate straight-edge), 1 supervisor (measure & mark)

• Procedure:

  1. Place straight-edge on the surface at starting point.
  2. Insert wedge at maximum gap between edge and surface; note reading.
  3. Slide straight-edge forward/backward by about 1.5 m and repeat.
  4. Mark locations where undulation exceeds permissible limits.

• Measurement:

  • The wedge reading indicates the maximum surface irregularity (undulation) at that point.

Typical Specification for Surface Irregularity (IRC guidelines)

Summary Diagram of Measurement Setup

graph LR
A[Straight-edge (1.5m)] -- placed on --> B[Surface]
B -- gap measured by --> C[Graduated Wedge]
C -- reading taken by --> D[Supervisor]
E[Workmen] -- operate --> A

Note: Mark all points exceeding the tolerance for rectification by grinding, filling, or re-laying.

This method ensures uniform surface evenness critical for ride quality and durability.

Key Specifications & Tests for Aggregate and Binding Material (IRC SP 11)

1. Aggregate Characteristics

• Gradation (% Passing IS Sieves):
  Typical sieve sizes and specification limits (example for WBM/base):

  IS Sieve (mm)	Passing % Range
  50	95 - 100
  20	45 - 75
  4.75	25 - 45
  600 micron	20 - 30
  150 micron	0 - 6

• Aggregate Impact Value (IS: 2386 Part IV):

  • Test frequency: 1 per 200 m³
  • Indicates toughness and resistance to impact.

• Flakiness Index:

  • Measures shape characteristics; lower values preferred for better compaction.

2. Binding Material

• Plasticity Index (PI) of filler material (IS: 2720 Part V):

  • Test frequency: 1 per 25 m²
  • PI affects workability and stability.

• Moisture Content & Compaction:

  • Natural moisture test: 1 per 250 m³ soil
  • Standard Proctor test for OMC and maximum dry density (MDD) to determine compaction characteristics.

3. Compaction Characteristics

4. Quality Control

• Maintain records in proforma Q/R/3 (Aggregate/Binding Material).
• Statistical control charts for gradation ensure compliance within limits (UCL, LCL).

Summary Table: Aggregate Gradation Control Example

Key Specifications for Asphaltic Concrete Surfacing (IRC SP 11, Clause 5.5):

• Reference Standard: IRC 29-1968 for 4 cm asphaltic concrete surface course.
• Materials: Bituminous binder, filler, fine & coarse aggregates as per IRC 29-1968.
• Base Preparation: Per Clause 5.2.3.1; may require bituminous leveling course for undulations.
• Mix Design:
  • Gradation and binder content must satisfy IRC design criteria.
  • Job-mix formula based on site materials; variations within ±0.3% binder by weight allowed.
• Mixing & Laying:
  • Binder temp: 150°–177°C; aggregate temp: 155°–163°C; max temp difference 14°C.
  • Use mechanical mixers and pavers.
  • Immediate rolling after spreading.
• Quality Control Tests (Table 5.2):

Aggregate Gradation Typical Limits (IRC SP 11)

IRC SP 11: Documentation and Reporting Procedures - Key Points

1. Quality Control Functions

• Director Quality Control: Policy implementation, training, R&D liaison, report analysis, and major project quality oversight.
• Quality Control Divisions: Assist field officers, inspect works, test materials, suggest improvements, identify materials, and train site staff.

2. Sample Forms for Quality Tests (Proformae Q/R/1 to Q/R/12)

• Frequency: As per handbook requirements.
• Records: Maintain in serially numbered registers, linked with payment bills every third running bill.

3. Key Tables & Specifications

• Aggregate Gradation Control Chart (Fig. 7): Statistical control with Upper Control Limit (UCL) and Lower Control Limit (LCL) to ensure compliance.
• Proctor Density, CBR, Deleterious Content, Moisture Content: Recorded for borrow materials.
• Standard Specifications: Refer IRC standards like IRC 14, 15, 19, 20, 27, 29, 36, 48, 57, etc., for detailed material and construction specs.

4. Statistical Quality Control Approach

• Plot sieve analysis results against specified limits.
• Check if mean (x) and control limits (x ± 2j) lie within specification zones.
• Non-compliance indicated if control limits exceed stipulated zones.

flowchart TD