Method of measurement of building and civil engineering works, Part 25: tunnelling

IS 1200 Part 25 (1971) - Scope & Key Specifications

• Scope: Covers measurement methods for grouting works, especially pack and/or pressure grouting over concrete lining.

• Measurement Basis:

  • Grouting measured by weight of cement in grout forced into holes.
  • Additions like stone dust measured separately in loose dry state by approved boxes.

• Measurement Precision (Clause 2.3):

  • Linear dimensions: nearest 0.01 m
  • Areas: nearest 0.01 m²
  • Volumes: nearest 0.01 m³
  • Weight: nearest 0.1 kg

Measurement Summary Table

Notes:

• Cement weight is primary for grout measurement.
• Stone dust and other additives measured separately before mixing.
• Measurement is net, after fixing in position.

This ensures standardized, accurate quantification of grouting in construction works per IS 1200 Part 25.

flowchart TD
    A[Grouting Work] --> B[Measure Cement Weight]
    A --> C[Measure Stone Dust/Additives]
    B --> D[Weight in kg (nearest 0.1)]
    C --> E[Loose dry volume by boxes]
    D & E --> F[Total Grouting Measurement]

IS 1200 Part 25: General Principles and Definitions for Tunneling Measurement

This part of IS 1200 deals with the method of measurement specifically for tunneling works. Key points include:

General Principles:

• Measurement is based on actual work done on site.
• Quantities are expressed in cubic meters (m³) for excavation and square meters (m²) for lining or surface works.
• Measurements follow IS 1200 Part II (1974) for related civil engineering works.

Key Specifications:

• Excavation: Measure net volume after deduction of overlaps or bulking.
• Support and Lining: Measure surface area of lining excluding overlaps.
• Overbreak and Underbreak: Deduct or add as per site measurements.

Reference Table (Typical):

Formula for Excavation Volume:

[ V = A \times L ]

• ( V ) = volume of excavation (m³)
• ( A ) = cross-sectional area of tunnel (m²)
• ( L ) = length of tunnel (m)

flowchart TD
    A[Tunnel Excavation] --> B[Measure Cross-Sectional Area (A)]
    B --> C[Measure Length (L)]
    C --> D[Calculate Volume V = A × L]
    D --> E[Deduct Overbreak Volume]
    E --> F[Final Excavation Quantity]

Note: Always refer to IS 1200 Part II (1974) for detailed measurement rules applicable to tunneling.

IS 1200 Part 25: Method of Measurement of Excavation (Tunnel)

Key Points & Formulas

• Excavation Volume (Clause 3.3):
  Measure volume (m³) within the hypothetical 'B' line (pay line), defined by the engineer-in-charge, regardless of actual excavation limits.
  [ \text{Excavation Volume} = \text{Cross-sectional area within 'B' line} \times \text{Length of tunnel} ]

• Enlarged Excavation (Clause 3.3.2):
  If the excavation is enlarged beyond the original 'B' line, measure the extra volume separately between the original and revised 'B' lines.

• Site Information (Clause 2.7):
  Document strata types, ridges/valleys crossed, and tunnel inclination for accurate volume estimation.

Typical Measurement Steps

1. Define the 'B' line cross-section (pay line).
2. Calculate cross-sectional area (A) within 'B' line.
3. Multiply by tunnel length (L): [ V = A \times L ]
4. For enlarged excavation, measure volume between old and new 'B' lines separately.

Reference Table (Example Cross-Section Area Calculation)

flowchart LR
    A[Start: Define 'B' line] --> B[Measure Cross-sectional Area]
    B --> C[Multiply by Tunnel Length]
    C --> D{Is Excavation Enlarged?}
    D -- Yes --> E[Measure Volume between Old & New 'B' lines]
    D -- No --> F[Record Volume as per '

IS 1200 Part 25: Measurement of Supports - Key Points

1. Measurement Basis

• Temporary Supports: Measured by area supported = Peripheral length × Linear tunnel length.
• Permanent Supports: Measured by weight (kg) including all components.

2. Components Included in Weight Measurement (Permanent Supports)

• Steel sections (structural, riveted, welded)
• Lagging, butt plates, feather plates
• Bolts, nuts, dowels, wedges, tie rods, spikes, drift pins
• Temporary timber spreaders
• Concrete pedestals (if any)
• Blocking and back packing with excavated material

3. Important Notes

• Strengthening existing supports by adding members is measured separately.
• Weight measurement includes all fastening and connecting elements.

Summary Table

flowchart LR
    A[Supports] --> B[Temporary Support]
    A --> C[Permanent Support]

    B --> D[Measured by Area]
    D --> E[Perimeter × Tunnel Length]

    C --> F[Measured by Weight (kg)]
    F --> G[Steel Sections + Fasteners + Plates]
    F --> H[Timber Spreaders + Concrete Pedestals + Back Packing]

This ensures comprehensive measurement for accurate billing and construction control per IS 1200 Part 25.

IS 1200 Part 25: Measurement of Concrete Lining – Key Points

1. Volume Measurement (Clause 5.1)

• Measure concrete volume between formwork (or steel shell outer surface) and the pay line ('B' line).
• Include formwork volume.
• Do NOT deduct reinforcement volume.
• Deduct volume of permanent steel supports from total concrete volume.

2. Precast Concrete Blocks (Clause 4.5)

• Measure precast blocks separately if used as lagging.
• Deduct their volume from concrete lining if placed within 'B' line.

3. Overbreak Concrete (Clause 5.1.1)

• Concrete filling overbreaks beyond 'B' line is included in the main lining or primary concrete lining volume.

4. Grouting Over Concrete Lining (Clause 4.5)

• Measure concrete filling space between 'B' line and precast/steel lining based on cement weight:
  • a) Manual placement (ledge beams, curbs).
  • b) Mechanical placement (pumps, placers).

Summary Table: Volume Measurement

Formula for Concrete Volume (V):

[ V = \text{Volume between formwork/steel shell and B line} - \text{Volume of permanent steel supports} ]

flowchart LR
    A[Formwork or Steel Shell Outer Surface]
    B[B Line (Pay Line)]
    C[Concrete Lining Volume]
    D[Permanent Steel Supports]
    E[Reinforcement]
    F[Precast Blocks]

    A -->|Defines inner boundary| C
    B -->|Defines outer boundary| C
    D -->|Volume deducted| C
    E -->|Volume NOT deducted| C
   

IS 1200 Part 25: Pack and Pressure Grouting Over Concrete Lining

Key Specifications & Measurement

• Grout Holes (Clause 6.1):

  • Measured in running meters for holes drilled through concrete/rock.
  • Holes through steel liners measured by number.

• Grouting Measurement (Clause 6.4):

  • Based on weight of cement in grout forced into holes.
  • Stone dust/additives measured separately in loose dry state by approved boxes.

• Concrete Filling (Clause 5.1.1):

  • Concrete for overbreaks beyond 'B' line included with main or primary lining measurement.

• Grouting Behind Supports (Clause 4.3):

  • Measured by weight of cement consumed, including materials used.

Typical Grout Volume Calculation

[ \text{Volume of grout} = \pi \times r^2 \times L ]

• (r) = radius of grout hole (m)
• (L) = length of grout hole (m)

Cement Weight in Grout

[ W_c = V_g \times \rho_g \times C_f ]

• (W_c) = weight of cement (kg)
• (V_g) = volume of grout (m³)
• (\rho_g) = density of grout (kg/m³)
• (C_f) = cement fraction in grout mix

Summary Table: Measurement Units

flowchart TD
    A[Drill grout holes] --> B[Measure length (m)]
    B --> C[Inject grout]
    C --> D[Measure cement weight in grout (kg)]
    C --> E[Measure additives separately]
    D --> F[Calculate grout volume and materials]

For detailed execution, refer to IS 1200 Part 25 and related cement/concrete works standards.

IS 1200 Part 25: Measurement of Pumping and Dewatering

Key Specifications (Clause 2.5)

• Pumping measurement is done separately for each stage, including intermediate stages.
• Units of measurement:
  • Electrical pumping: kilowatt-hours (kW·h) or brake power hours (bp·h).
  • Pneumatic pumping: measured by rated compressor capacity in cubic meters of air delivered per hour.
  • Special pumping (no electricity): measured in kilolitres or kilowatt-hours of water, if specific provisions exist.

Measurement Rules

• Each pumping stage is measured separately.
• Pneumatic air volume is the basis when pneumatic pumping is used.
• For grouting (Clause 6.4), measurement is by weight of cement actually forced into holes; stone dust and additives are measured separately in loose dry state.

Summary Table

This ensures accurate quantification of pumping/dewatering efforts for billing and project control as per IS 1200 Part 25.

IS 1200 Part 25: Measurement of Water Pressure Testing

Key Specifications:

• Clause 6.3:

  • Water pressure testing measurements must be done separately for each hole and enumerated individually.

• Clause 6.4 (Grouting Measurement):

  • Grouting quantity is measured by the weight of cement actually forced into holes.
  • Additives like stone dust measured separately in loose dry state before mixing.
  • Measurement by approved box sizes.

Measurement Units:

• Water pressure testing: per hole basis.
• Grouting: weight of cement (kg or tonnes).
• Additives: volume in loose dry state.

Additional Notes:

• Pumping (Clause 2.5) is measured in:
  • kW hours or bp hours for electric pumping.
  • Cubic meters of air/hour for pneumatic pumping.
  • Kilolitres or kW hours for special pumping without electricity.

Summary Table:

Conceptual Flow for Water Pressure Testing & Grouting:

flowchart TD
    A[Start] --> B[Identify Each Hole]
    B --> C[Conduct Water Pressure Test]
    C --> D[Record Pressure Data Per Hole]
    D --> E[Prepare Grout Mix]
    E --> F[Measure Cement Weight]
    F --> G[Measure Additives Volume]
    G --> H[Inject Grout into Hole]
    H --> I[Record Quantity Injected]
    I --> J[Complete Measurement]

For detailed methodology, refer to IS 1200 Part II (Cement and Concrete Works) for cement/gr

IS 1200 Part 25: Booking of Dimensions and Rounding Off

Booking of Dimensions (Clause 2.2)

• Dimensions must be booked consistently in the order:
  Length → Width → Height/Depth/Thickness

Measurement Accuracy (Clause 2.3)

Rounding Off (Clause 0.6)

• Follow IS 2-1960 for rounding.
• Retain the same number of significant digits as specified in the standard.
• Round off final measured or calculated values accordingly.

Additional Notes

• Special pumping quantities measured separately in kilolitres or kilowatt-hours (Clause 2.5).
• Measurements are net, based on fixed-in-place work.
• Consistency and clarity in booking and rounding avoid disputes and ensure uniformity.

flowchart LR
    A[Start: Measure Dimensions] --> B{Order of Booking?}
    B -->|Yes| C[Length → Width → Height/Depth]
    C --> D[Record Values with Precision]
    D --> E{Round Off as per IS 2-1960}
    E --> F[Final Booked Dimension]

This ensures uniform measurement and billing across civil engineering and tunneling works per IS 1200 Part 25.

IS 1200 Part 25: Classification of Tunnel Excavation Items

Key Classifications (Clause 3.1)

• a) Excavation in hard rock
  • No supports required.
• b) Excavation in soil or soft/hard rock
  • Temporary or permanent supports needed during excavation (refer IS 1200 Part 1 for soil classification).

Note: Supports are measured separately (Clause 4).

Important Specifications

• Site Description (Clause 2.7):
  • State strata details, ridges, valleys crossed.
  • Mention tunnel inclination.

Measurement Principles (from IS 1200-25)

• Excavation quantities measured by volume.
• Separate measurement for supports.
• Follow general rules for civil engineering works.

Reference Table: Tunnel Excavation Classification Summary

This classification ensures clear measurement and billing for tunneling works based on ground conditions and support requirements.

IS 1200 Part 25: Measurement of Overbreaks - Key Points

Overbreak Measurement (Clause 3.3.1)

• Measure overbreaks beyond 'B' line separately.
• Overbreaks due to carelessness/negligence certified by Engineer-in-Charge are not measured separately.

Concrete Filling (Clause 5.1.1)

• Concrete to fill overbreaks beyond 'B' line is measured with main concrete lining or included in primary concrete lining if done.

Grouting Measurement (Clause 6.4)

• Grouting measured by weight of cement actually forced into holes.
• Stone dust or additives measured separately in loose dry state by approved boxes.

Summary Table for Overbreak & Grouting Measurement

Practical Notes:

• Always ensure Engineer-in-Charge certification for overbreak classification.
• Use weighing scales for cement in grout; volumetric boxes for additives.
• Overbreak volume = Measured volume - Design volume (within 'B' line).

flowchart LR
    A[Excavation] --> B{Overbreak?}
    B -- Yes --> C[Measure separately]
    B -- No --> D[Included in main lining]
    C --> E{Cause?}
    E -- Negligence --> F[Exclude from separate measurement]
    E -- Otherwise --> G[Include in measurement]
    G --> H[Concrete filling measured with lining]
    F --> D

This ensures accurate billing and quality control in tunneling works per IS 1200 Part 25.

IS 1200 Part 25: Measurement of Timber & Precast Concrete Lagging

Key Points & Specifications

• Precast Concrete Lagging (Clause 4.5):

  • Measure volume of precast concrete blocks separately.
  • Deduct volume of blocks from concrete lining volume if within 'B' line.
  • Refer IS 1200 Part II (Concrete Works) for concrete lining measurement.

• Temporary & Permanent Supports (Clause 4.3):

  • Measure by weight (kg) including steel sections, lagging, bolts, nuts, tie rods.

• Timber Lagging (Clause 4.3.1):

  • Measure timber supports separately by volume or as per IS 1200 Part XXI (Woodwork).

Typical Measurement Formulas

Reference Standards

• IS 1200 Part II – Concrete Works (for concrete lining)
• IS 1200 Part XXI – Woodwork (for timber measurement)

flowchart TD
    A[Lagging Measurement] --> B[Precast Concrete Blocks]
    A --> C[Timber Lagging]
    B --> D[Measure Volume (m³)]
    D --> E[Deduct from Concrete Lining Volume]
    C --> F[Measure Volume (m³) as per IS 1200 Pt XXI]
    A --> G[Temporary/Permanent Supports]
    G --> H[Measure Weight (kg) including steel & lagging]

This ensures accurate quantity estimation for billing and construction control.

IS 1200 Part 25: Measurement of Rock Bolts & Steel Supports

Rock Bolts Measurement (Clause 4.7 & 4.6)

• Measured by weight (kg) including:
  • Rock bolt body + threaded portion
  • Wedges or anchoring devices
  • Washers and nuts
  • Installation charges
• Drilling holes measured separately in running meters.

Steel Supports Measurement (Clause 4.3 & 4.2)

• Measured by total weight (kg) including:
  • Steel sections
  • Lagging (if any)
  • Butt plates, feather plates
  • Bolts, nuts, tie rods
  • Temporary timber spreaders, concrete pedestals
  • Back packing with excavated material

Summary Table

Notes:

• Strengthening existing supports by adding members is measured separately.
• Weight-based measurement ensures accurate billing for materials and installation.

flowchart LR
    A[Rock Bolt] --> B[Weight in kg]
    B --> C[Includes bolts, wedges, nuts, washers]
    D[Drilled Hole] --> E[Length in meters]
    F[Steel Supports] --> G[Weight in kg]
    G --> H[Steel sections, lagging, bolts, plates, tie rods]

This method ensures precise quantification of materials and labor for rock bolts and steel supports.

IS 1200 Part 25: Measurement Units and Decimal System

Key Specifications (Clause 2.3):

• Linear dimensions: Measured to nearest 0.01 m
• Areas: Measured to nearest 0.01 m²
• Volumes: Measured to nearest 0.01 m³
• Weight: Measured to nearest 0.1 kg

Special Measurement (Clause 2.5):

• Special pumping measured separately in:
  • Kilolitres (kL) when no electricity is available
  • Kilowatt-hour (kWh) of water, if electric pumping is used

Rounding Off Rules:

• Follow IS 2-1960 for rounding numerical values.
• Retain the same number of significant digits as specified in this standard.

Summary Table:

Notes:

• Measurements are net and fixed in place.
• Decimal system ensures uniformity and clarity in civil engineering measurements.
• Precision supports accurate estimation and payment settlements.

flowchart TD
    A[Measurement] --> B[Linear Dimensions]
    A --> C[Area]
    A --> D[Volume]
    A --> E[Weight]
    A --> F[Special Pumping]

    B --> |Nearest 0.01 m| B1[Linear]
    C --> |Nearest 0.01 m²| C1[Area]
    D --> |Nearest 0.01 m³| D1[Volume]
    E --> |Nearest 0.1 kg| E1[Weight]
    F --> |kL or kWh| F1[Special Pumping]

This ensures consistent, accurate measurement for building and civil engineering works as per IS 1200 Part 25.

IS 1200 Part 25 Amendments & Revisions Summary

• Clause 2.7 (Page 5): Deleted completely.

• Clause 3.1(b) (Page 5):
  Replace reference
  IS 1200 (Part 1) - 1974*
  with
  IS 1200 (Part 1) : 1992*
  Footnote:
  "Method of measurement of building and civil engineering works: Part 1 Earthwork (fourth revision)."

• Clause 4.5 (Page 6):
  Replace
  [see IS:1200(Part II)-1968+]
  with
  [see IS:1200(Part II)-1974+]

• Clause 5.1 (Page 7):
  Replace
  [see also IS:1200 (Part II)-1968*]
  with
  [see also IS:1200(Part II)-1974*]

• Amendment No. 3 (April 1981):
  Applies to IS:1200(Part XXV)-1971, second revision for tunneling measurement.

Key Points:

• Amendments update references to newer IS parts (mostly from 1968/1974 to 1992 versions).
• Footnotes clarify the latest revision of related parts.
• No direct formulas or tables are amended here; mainly cross-referencing updates.

If you need formulas or tables for tunnel measurement or earthwork, refer to IS 1200 Part 1 (1992) and Part II (1974) as updated by these amendments.