Autoclaved reinforced cellular concrete floor and roof slabs

IS 6073: Scope & Key Specifications

Scope (Clause 3.0)

• Defines terms related to precast concrete slabs covered by this standard.

Key Physical Properties (Clause 5.1 & Table 2)

Table 2: Compressive Strength & Thermal Conductivity

• Note: Strength is average of 3 samples; no individual < 85% of average.

Structural Design (Clause 9)

• Load design per IS 875.
• Dead load = slab density + reinforcement mass.

Rounding Off (General)

• Follow IS 2:1960 for numerical rounding, matching significant digits.

flowchart LR
    A[Physical Properties] --> B[Density (IS 6441 Part 1)]
    A --> C[Drying Shrinkage ≤ 0.09% (IS 6441 Part 2)]
    A --> D[Residual Water Content Declared]
    A --> E[Compressive Strength & Thermal Conductivity (Table 2)]
    A --> F[Fire Resistance ≥ 2h (IS 3809)]
    G[Structural Design] --> H[Load per IS 875]
    G --> I[Dead Load = Density + Reinforcement]

This summary covers the **scope, physical

IS 6073 References Summary

• Key Indian Standards Referenced (Annex A):

• Physical Properties (Clause 5.1 & Table 2):

• Testing Protocol (Clause 13.5.2):

  • If sample fails, test double samples.
  • Lot passes if no failures in second test.

• Design Loads: Use IS 875 for dead, imposed, wind, snow, and special loads.

Summary Diagram: Reference Flow

graph LR
A[IS 6073] --> B[Physical Properties (IS 6441, IS 3346)]
A --> C[Material Specs (IS 269, IS 383, IS 432)]
A --> D[Design Loads (IS 875)]
A --> E[Earthquake Design (IS 1893)]
A --> F[Fire Resistance (IS 3809)]
A --> G[Testing Procedures (Clause 13.5.

IS 6073: Definitions & Key Specifications

1. Definitions (Clause 3.0)

• Standard definitions apply to autoclaved cellular concrete slabs and related terms.

2. Physical Properties (Clause 5.1 & Table 2)

3. Structural Design (Clause 9)

• Design loads per IS 875.
• Dead load based on density + reinforcement mass.

4. Manufacturer's Technical Literature (Clause 11.2)

Must include:

• Design load & deflection
• Ultimate load
• Residual water content
• Hole provisions
• Storage & handling instructions
• Thermal conductivity data

flowchart TD
    A[Slab Class] --> B[Compressive Strength]
    A --> C[Thermal Conductivity]
    B --> D[Min Strength (N/mm²)]
    C --> E[Max Thermal Conductivity (kcal/m/h/°C)]
    F[Physical Properties] --> A
    F --> G[Density]
    F --> H[Drying Shrinkage]
    F --> I[Fire Resistance]

References: IS 6441 (Parts

Key Materials Specifications from IS 6073 (Clause 5.1 & related)

Table 2: Compressive Strength & Thermal Conductivity

• Note: Compressive strength is average of 3 samples; no individual < 85% of average.

Reinforcement Protection (Clause 7.1)

• Reinforcement must have corrosion-resistant coating per IS 6441 (Part 4).
• Minimum concrete cover: 15 mm (to achieve fire resistance).

Design Load

• Use IS 875 for load calculations.
• Dead load based on specified densities + reinforcement mass.

This ensures material quality, durability, and fire safety of autoclaved cellular concrete slabs per IS 6073.

IS 6073 - Physical Properties Summary

Key Specifications (Clause 5.1)

• Density (Excluding Reinforcement): As per IS 6441 (Part 1), within specified range.
• Drying Shrinkage: ≤ 0.09% (IS 6441 Part 2).
• Residual Water Content: Declared by manufacturer.
• Compressive Strength & Thermal Conductivity: See Table 2 below (IS 6441 Part 5 & IS 3346).
• Fire Resistance: ≥ 2 hours (IS 3809).

Table 2: Compressive Strength & Thermal Conductivity

Note: Compressive strength = average of 3 cubes; no individual < 85% of average.

Additional Notes

• Design loads per IS 875; dead load uses densities from Clause 5.1 + reinforcement mass.
• Slabs have tongue & groove or groove-to-groove edges for force transfer.
• Manufacturer must provide technical data including load, deflection, ultimate load, residual moisture, hole provisions, handling, and thermal conductivity.

References for Testing & Design

• IS 6441 (Parts 1,2,5) – Testing methods for density, shrinkage, strength.
• IS 3346 – Thermal conductivity.
• IS 3809 – Fire resistance.
• IS 875 – Design loads.

flowchart LR
    A[Physical Properties] --> B[Density per IS 6441 (Part 1)]
    A --> C[Drying Shrinkage ≤ 0.09%]
    A --> D[Compressive Strength & Thermal Conductivity]
    A --> E[Fire Resistance ≥ 2 hrs]
    D --> F[See Table 2]
    F --> G[Class A to E]

This concise summary covers key physical properties,

IS 6073: Dimensions and Tolerances Summary

1. Preferred Dimensions (Clause 6.1.1)

• Length: 1 m to 6 m
• Width: 300 mm to 600 mm
• Thickness: 75 mm to 250 mm (increments of 25 mm)

Other sizes allowed by mutual agreement.

2. Dimensional Tolerances (Clause 6.2)

3. Form Tolerances (Clause 6.3 & Fig. 2, Table 1)

• Form tolerances apply to floor and roof slabs.
• Typical parameters include flatness, straightness, and squareness.
• Refer to Table 1 (not provided here) for exact permissible deviations.

Summary Diagram: Dimension vs Tolerance

graph LR
A[Dimension ≤ 500 mm] -->|Tolerance ±2 mm| B[Acceptable Range]
C[Dimension > 500 mm] -->|Tolerance ±5 mm| D[Acceptable Range]

Note: For detailed form tolerances, consult Table 1 and Fig. 2 of IS 6073, which specify limits for slab flatness and edge straightness.

IS 6073: Manufacture and Finish - Key Points

1. Manufacture Requirements (Clause 7.1)

• Reinforcement:
  • Located as per design.
  • Protected against corrosion with coatings conforming to IS 6441 (Part 4).
  • Minimum concrete cover: 15 mm for fire resistance and durability.

2. Technical Literature (Clause 11.2)

Manufacturer must provide:

• Design load & deflection.
• Ultimate load.
• Residual water content on delivery.
• Provisions for making holes.
• Storage and handling instructions (critical to avoid warp/torsion).
• Thermal conductivity of product classes.

3. Form Tolerances for Floor and Roof Slabs (Clause 6.3, Table 1)

4. Physical Properties (Clause 5.1, Table 2)

• Drying shrinkage ≤ 0.09%
• Fire resistance ≥ 2 hours (IS 3809)

flowchart TD
    A[Manufacture] --> B[Reinforcement Placement

IS 6073: Structural Requirements Summary

1. Physical Properties (Clause 5.1)

• Density: As per IS 6441 (Part 1).
• Drying Shrinkage: ≤ 0.09% (IS 6441 Part 2).
• Residual Water Content: Declared by manufacturer.
• Compressive Strength & Thermal Conductivity (Table 2):

• Fire Resistance: ≥ 2 hours (IS 3809).

2. Structural Design (Clause 9)

• Design per IS 875 loading codes.
• Dead load includes slab density + reinforcement mass.
• Reinforcement must have corrosion protection per IS 6441 (Part 4).
• Minimum concrete cover: 15 mm (to meet fire resistance).

3. Tolerances (Table 1)

• Flatness warp tolerance up to ±6 mm over 2 m.
• Edge straightness ±3 mm.
• Squareness ±5 mm.

4. Ultimate Load (Clause 9.3)

• Manufacturer to specify ultimate load; must meet or exceed minimum values (not specified here).

flowchart TD
    A[Physical Properties] -->|Density, Shrinkage| B[Material Quality]
    B --> C[Compressive Strength & Thermal Conductivity]
    C --> D[Structural Design]
    D --> E[Load as per IS 875 + Reinforcement]
    E --> F[Reinforcement Protection & Cover]
    F --> G[Fire Resistance & Durability]

Note: Detailed design methods are manufacturer’s responsibility; users must verify compliance and acceptance tests.

IS 6073: Load Requirements Summary

Ultimate Load (Clause 1.5 & 9.3)

[ \boxed{ Ultimate\ Load = 1.5 \times Design\ Dead\ Load + 2.2 \times Design\ Imposed\ Load } ]

• Manufacturer must specify ultimate load ≥ above value.
• Slabs designed per IS 875 loading standards.
• Dead load = slab density (Clause 5.1) + reinforcement mass.

Load Testing (Clause 2.2)

• Apply half design load for 30 minutes.
• Load applied via two weights at outside quarter points of effective span.

Physical Properties (Clause 5.1 & Table 2)

• Density as per IS 6441 (Part 1).
• Drying shrinkage ≤ 0.09% (IS 6441 Part 2).
• Fire resistance ≥ 2 hours (IS 3809).
• Compressive strength: average of 3 cubes; no single below 85% of average.

Design Note

• Use densities from Clause 5.1 for dead load calculation.
• Confirm ultimate load per formula before slab design.

flowchart LR
    A[Design Dead Load] -->|x1.5| C[Ultimate Load]
    B[Design Imposed Load] -->|x2.2| C
    C --> D[Slab Design per IS 875]
    D --> E[Load Testing: Half Load, 30 min]

IS 6073: Storage and Handling of Autoclaved Cellular Concrete Slabs

Key Specifications (Clause 10 & 11.2)

• Storage:
  • Stock slabs on planks/supports, avoid ground contact.
  • Separate stacks for different densities/shapes.
• Handling:
  • Follow manufacturer's instructions.
  • Reject damaged slabs.
  • Cutting slabs only with designer/engineer approval.
• Deformation Risk: Improper handling can cause permanent torsion/warp.

Physical Properties (Clause 5.1 & Table 2)

• Residual water content declared by manufacturer.
• Drying shrinkage ≤ 0.09%.

Handling Notes:

• Avoid slab deformation (warp, torsion).
• Slabs shall not be cut without permission.
• Reinforcement cover ≥ 15 mm for fire resistance.

Summary Diagram: Storage Stack Setup

flowchart TB
    A[Ground] -->|No direct contact| B[Planks/Supports]
    B --> C[Slab Stack]
    C --> D{Different Densities/Shapes}
    D --> E[Separate Stacks]

Ensure compliance with IS 875 for load design and IS 1893/IS 4326 for seismic diaphragm action.

IS 6073: Marking Requirements for Precast Concrete Slabs

Key Marking Specifications (Clause 11 & 12)

• Location: Markings on the face not visible in the final structure.
• Mandatory Information (Clause 11.1):
  • Manufacturer identification
  • Year of manufacture
  • Slab designation
  • The words "Do not Cut"
  • The word "Top" on the slab face
• Special Markings (Clause 12.1.1):
  • Indicate load-carrying capacity limitations and correct handling/assembly positions.
  • Mark special support/lifting points.
  • Mark locations for permitted hole-making.

BIS Certification (Clause 11.3)

• Slabs may carry the BIS Standard Mark to indicate certification.

Form Tolerances (Clause 6.3 & Table 1)

• Refer to Table 1 for dimensional tolerances on slab length, width, thickness, and squareness.
• See Fig. 2 in the code for geometric tolerance illustrations.

Summary Table: Typical Marking Details

flowchart LR
    A[Slab Manufactured] --> B[Mark Non-Visible Face]
    B --> C{Markings}
    C -->|ID, Year, Designation| D[Slab Identification]
    C -->|Do not Cut| E[Cutting Warning]
    C -->|Top| F[Orientation Mark]
    A --> G[Mark Visible Face]
    G --> H[Handling & Hole Locations]

Note: Always cross-check with the latest IS 6073 edition for updated marking practices and tolerances.

IS 6073: Cost of Tests & Manufacturer's Certificate (Clause 12)

• Cost of Tests (Clause 12.3):

  • If test results do not conform to IS 6073, manufacturer bears the cost.
  • If test results conform to IS 6073, purchaser bears the cost.

• Manufacturer's Certificate:

  • Typically accompanies the product, certifying compliance with IS 6073 and test results.
  • Ensures traceability and quality assurance.

Sampling & Retesting (Clause 13.5.2):

Summary Table: Cost Responsibility for Tests

Key References for Tests & Materials (Annex A):

• IS 269: Ordinary Portland Cement
• IS 383: Aggregates for Concrete
• IS 456: Plain & Reinforced Concrete Code
• IS 1786: High Strength Steel Bars
• IS 1893: Earthquake Loads

flowchart TD
    A[Test Conducted] --> B{Test Result}
    B -->|Conforming| C[Cost borne by Purchaser]
    B -->|Non-conforming| D[Cost borne by Manufacturer]

This ensures clarity on financial responsibility and quality compliance under IS 6073.

IS 6073: Sampling and Criteria for Conformity (Clauses 13, 13.1, 13.5)

• Sampling Method (Clause 13.1):
  Representative samples of slabs must be drawn as per Clauses 13.2 to 13.5.2 unless otherwise agreed between purchaser and supplier.

• Criteria for Conformity (Clause 13.5):
  The slabs conform if all test results meet the specified requirements in the standard. Non-conformity in any test means the batch is rejected.

• Cost of Testing (Clause 12.3):

  • Manufacturer bears cost if slabs do not conform.
  • Purchaser bears cost if slabs conform.

Typical Sampling & Acceptance Criteria (Generalized)

Note: Refer to IS 6073 Clauses 13.2 to 13.5.2 for detailed sampling plans and acceptance numbers.

flowchart TD
    A[Start Sampling] --> B{Sample Size as per IS 6073}
    B --> C[Perform Tests]
    C --> D{All Tests Passed?}
    D -->|Yes| E[Batch Accepted]
    D -->|No| F[Batch Rejected]
    E --> G[Purchaser bears cost]
    F --> H[Manufacturer bears cost]

Summary: Follow IS 6073 Clauses 13.2-13.5.2 for sampling; all samples must meet criteria for batch acceptance; cost responsibility depends on conformity results.

IS 6073 Foreword - Key Points & Specifications

• Purpose: Defines terms and scope related to prefabricated concrete slabs.

• Ultimate Load (Clause 2.4):
  Load test on slab continues beyond design load in increments until failure.
  Ultimate Load = Total load at failure (used for safety checks).

• Manufacturer's Technical Literature (Clause 11.2): Must include:

  • Design load & deflection at design load
  • Ultimate load
  • Residual water content at delivery
  • Provisions for making holes
  • Storage & handling instructions (to avoid deformation)
  • Thermal conductivity of product classes

• Committee Composition: Diverse experts from government, industry, and research institutes ensure comprehensive standard development.

• Reference to Other Standards: Annex A lists related Indian Standards; users should check for latest editions.

Ultimate Load Testing Summary (Clause 2.4):

Storage & Handling Note:

• Improper storage can cause permanent torsion and warp in slabs.

flowchart TD
    A[Apply Design Load] --> B[Increment Load in Steps]
    B --> C{Slab Fails?}
    C -- No --> B
    C -- Yes --> D[Record Ultimate Load]

This summarizes the foreword essentials and key technical requirements from IS 6073.

IS 6073: Deflection and Ultimate Load Test for Autoclaved Reinforced Cellular Concrete Slabs

Key Specifications:

• Maximum allowable deflection:
  [ \delta_{max} \leq \frac{L_{eff}}{300} ] where (L_{eff}) = effective span of the slab.

• Load conditions:

  • Test load = Design imposed load + Self-weight of slab (Clause 9.2)
  • Load held for 30 minutes before measuring deflection (Clause B-2.4).

• Failure criteria:

  • Any visible cracking or
  • Deflection exceeding (L_{eff}/300) (Clause B-2.5).

Test Procedure Summary:

1. Apply total design load on slab.
2. Maintain load for 30 minutes.
3. Measure mid-span deflection.
4. Inspect for cracks.

Ultimate Load:

• The slab must sustain the design load without failure or excessive deflection.
• The ultimate load test verifies structural adequacy beyond service loads.

Formula Summary:

flowchart LR
    A[Apply Design Load + Self Weight] --> B[Hold for 30 minutes]
    B --> C{Check for Cracks?}
    C -- Yes --> F[Fail Test]
    C -- No --> D[Measure Mid-span Deflection]
    D --> E{Deflection ≤ L_eff/300?}
    E -- Yes --> G[Pass Test]
    E -- No --> F[Fail Test]

This ensures slab serviceability and safety per IS 6073 Annex B.

IS 6073: Committee Composition & Key Specifications

• Committee Composition:
  The technical committee responsible for IS 6073 formulation is detailed in Annex C under the Planning, Housing and Prefabricated Construction Sectional Committee, CED 51.

Key Specifications from IS 6073:

Compressive Strength & Thermal Conductivity (Table 2, Clauses 5.1 & 8)

• Note: Compressive strength is the average of 3 samples; no individual value should be < 85% of average.

Structural Design Reference

• Slabs must be designed per IS 875 loading standards.
• Dead load = slab density (Clause 5.1) + reinforcement mass.

flowchart TD
    A[Technical Committee] -->|Annex C| B(Planning, Housing & Prefabricated Construction Sectional Committee CED 51)
    B --> C[Formulates IS 6073 Standard]
    C --> D[Specifies Physical Properties]
    D --> E[Density, Shrinkage, Strength, Fire Resistance]
    C --> F[Specifies Design Requirements]
    F --> G[Loading per IS 875]

This summary provides the essential committee and technical data from IS 6073 for quick reference.