IS 1200 Part 2: Method of Measurement of Building and Civil Engineering Works (Concrete Works)
IS 1200 Part 2 is a crucial standard in the field of civil engineering that specifies the methods of measurement for concrete works. This standard provides a systematic approach to quantifying the various components and activities involved in concrete construction, ensuring consistency, accuracy, and clarity in construction documentation and project management.
Importance of Standardized Measurement
Standardized measurement methods are essential for several reasons:
- Accuracy: Ensures precise estimation of materials and costs.
- Consistency: Facilitates uniformity in construction documentation.
- Clarity: Reduces ambiguities and potential disputes among stakeholders.
- Efficiency: Streamlines the project management process by providing clear guidelines.
Key Sections of IS 1200 Part 2
1. General Principles
The standard outlines general principles for measuring concrete works, including:
- Measurement Units: Concrete is generally measured in cubic meters (m³) for volume.
- Description of Work: Clear and comprehensive descriptions of each work item, including specifications of the concrete mix, types of reinforcement, and finishes.
- Measurement Methods: Specific guidelines on how to measure different components of concrete works, ensuring precision and uniformity.
2. Plain and Reinforced Concrete
Plain and Reinforced Concrete:
- Plain Concrete: Concrete without reinforcement, used for non-structural elements such as flooring and paving.
- Reinforced Concrete (RCC): Concrete reinforced with steel bars, used for structural elements like beams, columns, slabs, and foundations.
Measurement Guidelines:
- Volume Calculation: The volume of concrete is calculated based on the dimensions of the formwork or the constructed element. Measurements should account for any openings or voids within the concrete structure.
- Reinforcement: The steel reinforcement is measured separately, usually by weight (kilograms or tonnes). The type, size, and spacing of reinforcement bars are specified in detail.
3. Formwork
Formwork is a temporary structure used to shape and support concrete until it gains sufficient strength. The standard specifies:
- Measurement Units: Square meters (m²) for the area of formwork.
- Types of Formwork: Includes formwork for different concrete elements such as slabs, beams, columns, and walls.
- Measurement Methods: Formwork is measured based on the contact area with concrete. Special considerations are made for curved and complex shapes.
4. Precast Concrete
Precast Concrete involves casting concrete elements in a controlled environment and then transporting them to the construction site. Key guidelines include:
- Measurement Units: Cubic meters (m³) for volume, and sometimes by the number of units for standard precast elements.
- Types: Includes precast beams, columns, slabs, and wall panels.
- Measurement Methods: Precast elements are measured by their overall dimensions, excluding any joints or connectors.
5. Concrete Finishes
Concrete finishes refer to the surface treatment of concrete to achieve a specific texture or appearance. The standard covers:
- Measurement Units: Square meters (m²) for the surface area of finishes.
- Types: Includes different finishes like smooth, textured, exposed aggregate, and patterned surfaces.
- Measurement Methods: The area of the finished surface is measured, and different types of finishes are specified in the contract documentation.
Detailed Method of Measurement
1. General Rules
- Accuracy: All measurements should be taken with the highest possible accuracy, using appropriate tools and techniques.
- Consistency: The same units and methods should be used throughout the project to maintain consistency.
- Description: Each item should be fully described, including the quality, type, and nature of work.
2. Specific Guidelines
Plain and Reinforced Concrete:
- Plain Concrete: Measured by volume. For example, a slab of dimensions 10m x 5m x 0.15m would have a volume of 10×5×0.15=7.5m^3.
- Reinforced Concrete: Measured by volume for the concrete and by weight for the reinforcement. For example, a beam of 6m length, 0.3m width, and 0.5m depth with 200kg of steel reinforcement would be described with both the concrete volume and the steel weight.
Formwork:
- Slabs: Measured by the area of the underside of the slab. For a slab of dimensions 10m x 5m, the formwork area is ( 10×5=50m^2 ).
- Beams and Columns: Measured by the area of the sides and bottom (for beams) or the perimeter (for columns). For a beam of 6m length, 0.3m width, and 0.5m depth, the formwork area is (
- 2×(6×0.5)+2×(6×0.3)+(0.3×0.5)=8.3 m^2 ).
Precast Concrete:
- Beams: Measured by volume or by the number of units. For a beam of 6m length, 0.3m width, and 0.5m depth, the volume is ( 6 \times 0.3 \times 0.5 = 0.9 \, \text{m}^3 ).
- Panels: Measured by surface area if they are thin, or by volume if they are thick.
Concrete Finishes:
- Smooth Finish: Measured by surface area. For a wall of dimensions 10m x 3m, the surface area is 10×3=30m^2
- Exposed Aggregate: Similar to smooth finish, measured by the surface area of the treated concrete.
Examples and Applications
1. Plain Concrete Example
For a concrete slab with dimensions 10m x 5m x 0.15m:
- Volume: 10m×5m×0.15m=7.5m^3
2. Reinforced Concrete Example
For a concrete beam of 6m length, 0.3m width, and 0.5m depth, with 200kg of steel reinforcement:
- Concrete Volume: 6m×0.3m×0.5m=0.9m^3
- Steel Reinforcement: 200kg
3. Formwork Example
For a column of 3m height, 0.4m width, and 0.4m depth:
- Formwork Area: 4×(0.4×3)+(0.4×0.4)=4.96m^2
4. Precast Concrete Example
For a precast concrete panel of dimensions 2m x 1m x 0.1m:
- Volume: 2m×1m×0.1m=0.2m^3
5. Concrete Finish Example
For a wall of dimensions 10m x 3m with a smooth finish:
- Surface Area: 10m×3m=30m^2
Special Considerations
Deductions and Additions:
- Openings and Voids: Deductions are made for openings such as windows and doors in concrete walls.
- Additional Features: Additions are made for features such as grooves, rebates, and other surface treatments.
Curved and Complex Shapes:
- Curved Surfaces: Formwork for curved surfaces is measured by the developed length of the curve multiplied by the height or width.
- Complex Elements: Special measurement techniques are applied for elements with complex geometries to ensure accuracy.
Conclusion
IS 1200 Part 2 provides comprehensive guidelines for the measurement of concrete works in civil engineering. Adhering to these standardized methods ensures precision, consistency, and clarity in construction documentation and project management. By following these guidelines, civil engineers can accurately estimate materials and costs, streamline project execution, and reduce potential disputes among stakeholders. This standard is essential for achieving high-quality construction outcomes and maintaining industry best practices.
These notes provide a detailed overview of IS 1200 Part 2, focusing on its application in concrete works within civil engineering. If you need any further elaboration on specific sections or additional details, feel free to ask!
