Precast Concrete Pipes (with and without Reinforcement)

IS 458: Scope - Key Specifications & Tables Summary

Scope (Clause 3.0):
Defines pipe dimensions and joint details for NP2, NP3, NP4, and P1, P2 class concrete pipes with rubber ring roll-on joints.

Key Tables for Spigot and Socket Dimensions (Clause 6.3)

• Table 13, 14, 18: Provide detailed dimensions for pipes with diameters from 80 mm to 2200 mm.
• Dimensions include:
  • Pipe Diameter (ØA)
  • Rubber Ring Chord Diameter & Internal Diameter
  • Critical dimensions: T, TS, DS, DS2, DS3, LSP, HT, K, S, H
• Tolerance on critical dimensions:

  Dimension Group	Tolerance (mm)
  T, HT, TS, H	As per barrel wall thickness tolerance (Clause 8.2)
  DS2	±2 to ±4 (depending on chord diameter)
  DS3	±3 to ±5 (depending on chord diameter)
  LSP	±4 to ±7 (depending on chord diameter)
  K & S	±0.75 to ±2.0 (depending on chord diameter)

Important Notes:

• Corners to be rounded off.
• Dimensions DS2, DS3, LSP, TS, T, H, S, HT, and K are critical and must strictly conform.
• Other dimensions are for guidance only.

Example Dimension Snippet (Pipe Diameter 80 mm, NP3 Class):

This scope ensures standardized pipe joint dimensions for compatibility and leak-proof connections in concrete pipes with rubber ring joints.

flowchart LR
    A[Pipe Diameter ØA] --> B[Rubber Ring Dimensions]
    B --> C{Critical Dimensions}
    C --> D

IS 458 Key References: Spigot & Socket Dimensions, Tolerances, and Reinforcement Weights

1. Spigot and Socket Dimensions (Rubber Ring Roll-on Joint)

• Applicable for P2, NP3, NP4, and P3 Class Pipes.
• Dimensions include:
  • Pipe Diameter (ØA)
  • Rubber Ring Chord Diameter & Internal Diameter
  • Critical dimensions: T, TS, DS2, DS3, LSP, K, HT, H, S (with specified tolerances)
• Dimensions are in mm and vary by pipe diameter from 80 mm up to 1200+ mm.

2. Tolerances on Critical Dimensions

3. Weight of Spirals (Hard Drawn Steel) in Socket (kg/number)

IS 458 - Key Definitions & Specifications Summary

1. Definitions (Clause 3.0)

• The standard defines terms related to concrete pipes, joints, and rubber rings for clarity and uniformity.
• Typical definitions include:
  • Spigot: Male end of pipe inserted into socket.
  • Socket: Female end receiving spigot.
  • Rubber Ring Joint: Flexible joint using rubber ring for watertightness.

2. Spigot and Socket Dimensions (Clause 6.3, Table 18)

• Table 18 provides detailed dimensions for P2 Class Pipes with rubber ring roll-on joints.
• Dimensions are in millimeters and include:
  • Pipe Diameter (e.g., 80 to 1000 mm)
  • Rubber Ring Chord/Internal Diameters
  • Critical dimensions: T, TS, DS2, DS3, LSP, K, HT, etc.
• Critical dimensions have specified tolerances to ensure proper joint fit and sealing.

3. Testing (Clause 10.2)

• Sample sizes and permissible defectives are specified (see Table 22).
• Ensures quality control excluding ultimate load tests.

Example: Pipe Diameter 300 mm (from Table 18)

Summary Diagram: Pipe Joint Components

graph LR
A[Spigot End] --> B[Rubber Ring]
B --> C[Socket End]
C --> D[Pipe Body]

This ensures a flexible, watertight joint per IS 458 specifications.

Note: For detailed design, always refer to the exact tables and tolerances in IS 458.

IS 458: Classification and Design Specifications for Concrete Pipes

1. Classification of Pipes (Clause 4.1)

2. Key Design Parameters

• Concrete strength: Minimum 35 N/mm² at 28 days.
• Test methods: Three edge bearing test for strength.

3. Example Table: NP1 (Unreinforced, Non-pressure Pipes) Barrel Thickness & Strength

4. Reinforced Concrete Pipes (NP2, NP3, NP4) Key Data

IS 458 Key Formulas, Tables & Specifications for Materials (Concrete Pipes)

1. Spigot and Socket Dimensions (Table 19)

• Specifies critical dimensions for P3 Class Pipes with Rubber Ring Roll-on Joints.
• Dimensions include pipe diameter, rubber ring chord/internal diameters, wall thickness (T), socket dimensions (DS, DS1, DS2, DS3), and tolerances.
• Tolerances on critical dimensions like T, HT, TS, H are related to barrel wall thickness (Clause 8.2).

2. Weight of Spirals in Socket (Table 20)

• Hard drawn steel spiral weights (kg/number) for different pipe classes (NP2, NP3, NP4, P1, P2, P3).
• Mild steel spiral weight increase factor: 1.4 (i.e., multiply hard drawn steel weight by 140/125).

3. Design & Strength Test Requirements for Concrete Pipes

IS 458 - Reinforcement Key Points

1. Reinforcement Types (Clause 5.4)

• Mild steel Grade I or medium tensile steel bars (IS 432 Part 1)
• Hard-drawn steel wire (IS 432 Part 2)
• Structural steel bars (IS 2062)
• Optional: Wire fabric (IS 1566), deformed bars/wires (IS 1786), prestressing wires (IS 1785)
• Max tensile stress per Clause 6.1 applies.

2. Reinforcement Design (Clause 6.2)

• Reinforcement extends full pipe length.
• Designed for proper placement and shape maintenance.
• Spiral reinforcement at pipe ends (150 mm length) to prevent damage:
  • Spiral spacing ≤ 50 mm or half the pitch, whichever is less.
  • End spirals included in total spiral reinforcement.

3. Longitudinal Reinforcement (Clause 6.1.3 & 6.1.2.1)

• Ensures cage rigidity and limits transverse cracking.
• Minimum values from Tables 2,3,5,6,8,9,10,11 depending on manufacturing process.
• For pipe length L (m), longitudinal reinforcement =
  [ \frac{L}{3} \times \text{longitudinal reinforcement for 3 m pipe} ]

Typical Formula Summary:

Diagram: Reinforcement Layout in Pipe

graph LR
A[Pipe Length L] --> B[Longitudinal Reinforcement]
A --> C[Spiral Reinforcement]
C --> D[End Spirals (150 mm length)]
D --> E[Spacing ≤ 50 mm or half pitch]

For detailed reinforcement areas, refer to IS 458 Tables 2,3,5,6,8,9,10,11.

IS 458: Manufacture Key Specifications & Tolerances

1. Dimensional Tolerances (Clause 8.2, Table 8.2)

Note: For pipes with flexible rubber ring joints, thickness tolerances near ends are reduced as per Tables 13-19 (spinning) and Tables 15-16 (vibrated casting).

2. Workmanship and Finish

• Pipe forms and dimensions must be accurate within specified tolerances.
• Surfaces and edges should be well-defined and true.
• Ends must be square with the longitudinal axis (Clause 7.1).
• Steel reinforcement quantity/disposition must meet minimums in Tables 2,3,5,6,8,9,10,11 or be validated by tests (Clause 6.2.2).

Summary Diagram of Tolerances:

graph TD
    A[Pipe Dimensions] --> B[Overall Length: +1%]
    A --> C[Internal Diameter]
    C --> C1[≤300 mm: ±3 mm]
    C --> C2[300-600 mm: ±5 mm]
    C --> C3[>600 mm: ±10 mm]
    A --> D[Barrel Wall Thickness]
    D --> D1[≤30 mm: +2/-1 mm]
    D --> D2[

IS 458: Dimensions and Tolerances Summary

1. Overall Length Tolerance

• ±1% of the standard length

2. Internal Diameter of Pipes

3. Barrel Wall Thickness Tolerances

Note: For flexible rubber ring joint pipes, thickness tolerance near ends is reduced as per Tables 13-19 (spinning) or Tables 15-16 (vibrated casting).

4. Critical Dimensions Tolerances (DS2, DS3, LSP, K, S)

Quick Reference Table for Barrel Wall Thickness Toler

IS 458: Inspection and Testing Key Points

1. Sample Size & Permissible Defectives (Clause 10.2 & 11.2.1.1)

• Lot conformity: Lot passes if defectives ≤ permissible number.

2. Tests on Specimens (Clause 10.2)

• Hydrostatic test
• Three-edge bearing test
• Permeability test
  (As per IS 3597)

3. Reinforced Concrete Collar Design (Table 21)

IS 458: Performance Requirements for Concrete Pipes

Key Specifications & Test Requirements:

1. Concrete Strength:

   • Minimum compressive strength:
     • NP class pipes: 35 N/mm² at 28 days.
     • Heavy-duty vibrated casting pipes: 50 N/mm² at 28 days.

2. Pipe Classes & Design Parameters:

3. Strength Test:

   • Three Edge Bearing Test measures ultimate load capacity (kN/linear meter).
   • Load to produce 0.25 mm crack specified for reinforced pipes.

4. Reinforcement Details:

   • Longitudinal bars: Mild steel or hard-drawn steel.
   • Spiral reinforcement: Hard drawn steel.
   • Weights and number of bars vary with pipe diameter and class.

Example: NP1 Class Pipe (Table 1)

IS 458: Sampling and Inspection Key Points

Sampling Size & Permissible Defectives (Table 22)

Inspection Criteria (Clause 11.2.1.1)

• A lot is declared conforming if the number of defectives in the sample does not exceed the permissible number in column 3 of Table 22.
• Sampling applies for tests under Clauses 8, 9, and 10.2 (excluding ultimate load test).

Summary:

• Use Table 22 to determine sample size and allowable defectives based on lot size.
• Inspection ensures quality by limiting defective pipes per sample.
• Applies to routine tests except ultimate load test, which has separate provisions.

flowchart LR
    A[Lot of Pipes] --> B{Determine Lot Size}
    B -->|Up to 50| C[Sample Size=8, Max Defectives=0]
    B -->|51-100| D[Sample Size=13, Max Defectives=1]
    B -->|101-300| E[Sample Size=20, Max Defectives=2]
    B -->|301-500| F[Sample Size=32, Max Defectives=3]
    B -->|501+| G[Sample Size=50, Max Defectives=5]
    C --> H[Inspect Sample]
    D --> H
    E --> H
    F --> H
    G --> H
    H --> I{Defectives ≤ Max?}
    I -->|Yes| J[Lot Accepted]
    I

IS 458 - Marking of Concrete Pipes (Clause 12.1.1 & 12.1.1.1)

• Each pipe may be marked with the Standard Mark as per BIS regulations.
• Use of Standard Mark is governed by the Bureau of Indian Standards Act, 1986.
• License for use of the Standard Mark must be obtained from BIS.
• Marking typically includes:
  • Manufacturer's identification
  • Pipe size and class
  • BIS Standard number (IS 458)
  • Date of manufacture
  • Standard Mark (if licensed)

Key Specifications for Marking:

• Marking ensures traceability and quality assurance.
• It is mandatory for licensed manufacturers.
• Marking should be clear, durable, and legible on the pipe surface.

Related Tables (Pipe Dimensions & Tolerances):

Example: Tolerances on Critical Dimensions

Summary Diagram of Marking Concept

flowchart LR
    A[Concrete Pipe] --> B[Marking]
    B --> C[Manufacturer ID]
    B --> D[Pipe Size & Class]
    B --> E[BIS Standard No. IS 458]
    B --> F[Date of Manufacture]
    B --> G[Standard Mark (if licensed)]

Note: For detailed marking format and conditions, refer to the BIS licensing provisions under the Bureau of Indian Standards Act, 1986.

IS 458 - Repair of Pipes: Key Points & Specifications

Repair Clause (9.1.4)

• Pipes damaged during manufacture or handling may be repaired.
• Repairs must be sound, properly finished, cured, and conform to the original pipe specifications.
• Acceptance of repaired pipes is at the purchaser's discretion.

Relevant Design & Strength Tables (for reference in repairs):

1. Class NP1 (Unreinforced, Non-pressure Pipes) - Table 1 (Clause 6.3)

2. Spigot and Socket Dimensions for Rubber Ring Joints - Table 13 (Clause 6.3)

• Critical dimensions like DS2, DS3, LSP, TS, T, H, S, HT, K have specified tolerances.
• Example: For 100 mm pipe, rubber ring internal diameter = 120 mm, T = 25 mm, HT = 84 mm.

3. Reinforced Concrete Pipes (Classes NP4, PI, P2, P3) - Tables 8 to 11

• Barrel wall thickness, reinforcement quantity (kg/m), and strength (kN/m) vary with pipe diameter and class.
• Minimum concrete compressive strength: 35 N/mm² at 28 days.
• Reinforcement details (longitudinal & spiral) critical for repair matching.

Summary for Repairs:

• Use original design dimensions and reinforcement details as reference.
• Ensure repaired section meets or exceeds strength test requirements (e.g., Three Edge Bearing Test).
• Proper curing and finishing are essential for durability.

flowchart TD
    A[Damaged Pipe] --> B{Repair Needed?}
    B -- Yes --> C[Repair with sound material]
    C --> D[Finish & Cure Properly]
    D --> E{Meets Spec?}
    E

IS 458: Packaging and Delivery - Key Specifications & Tables

1. Spigot and Socket Dimensions (Rubber Ring Roll-on Joint)

• Table 18 & Table 13 provide detailed dimensions for P2, NP2, and Pl class pipes.
• Critical dimensions include:
  • Rubber Ring Chord Diameter (e.g., 11-25 mm depending on pipe size)
  • Rubber Ring Internal Diameter
  • Dimensions like T, TS, DS, DS2, DS3, LSP, K, S, H, HT are critical and must conform strictly.
• Tolerances on critical dimensions vary by chord diameter:

2. Design & Strength Requirements (Table 1)

• For NP1 Class (Unreinforced, Non-pressure pipes):
  • Barrel wall thickness: 25-35 mm (varies by diameter)
  • Minimum collar length: 150-200 mm
  • Strength test ultimate load: 15.3 to 21.9 kN/m (increases with pipe size)

3. Packaging & Delivery Notes

• Pipes must be supplied with dimensions as per the tables unless mutually agreed.
• Critical dimensions must be within specified tolerances to ensure proper jointing and performance.
• Rubber rings must fit chord and internal diameters precisely for leak-proof joints.

Summary Diagram: Pipe Joint Critical Dimensions

graph LR
A[Pipe Spigot] --> B[Rubber Ring]
B --> C[Socket]
subgraph Critical Dimensions
T[T], TS[

IS 458 Annexures & Tables Key Highlights

1. Reinforced Concrete Collars (Table 22):

   • Collar dimensions and reinforcement for NP3 & NP4 classes.
   • Example for 300 mm diameter pipe:
     • Min Caulking Space: 16 mm
     • Min Thickness: 30 mm
     • Min Length: 150 mm
     • Longitudinal bars: 8 nos.
     • Steel weight: 0.11 kg (mild steel), 0.22 kg (hard drawn steel)

2. Spigot and Socket Dimensions (Table 19):

   • Critical dimensions for P3 class pipes with rubber ring roll-on joints.
   • Includes tolerances for dimensions like T, HT, DS2, DS3, LSP, K.
   • Example: For 200 mm pipe, T = 35 mm, TS = 45 mm, DS = 83 mm, etc.

3. Weight of Spirals in Socket (Table 20):

   • Spiral reinforcement weights (kg/pipe) for different pipe classes.
   • For 300 mm pipe: NP2 = 0.45 kg, NP3 = 0.45 kg, NP4 = 0.53 kg.

4. General Notes:

   • Collars ≥ 2200 mm use 6 mm thick mild steel plate (IS 2062).
   • Mild steel spiral weights increased by factor 140/125.
   • Soft mild steel wire spirals allowed up to 150 mm pipes with weight factor 140/84.

Summary Table: Collar Dimensions & Reinforcement (Excerpt)