This code provides comprehensive guidelines for ensuring the durability of concrete structures. It introduces a detailed system for classifying environmental exposure conditions and specifies corresponding requirements for concrete constituents, mix proportions, reinforcement cover, and quality assurance to achieve a target service life by mitigating deterioration mechanisms like reinforcement corrosion, sulphate attack, and alkali-aggregate reaction.
Lays down general principles and requirements for the design of structures, including safety, serviceability, and durability.
Quick Reference Values
Minimum concrete grade for 'Severe' exposure (RCC)M30
Maximum water-cement ratio for 'Very Severe' exposure0.45
Minimum cement content for 'Extreme' exposure400 kg/m³
Nominal cover for main reinforcement in 'Extreme' exposure75 mm
Maximum total acid-soluble chloride in concrete for Prestressed Concrete0.10% by mass of cementitious material
Minimum concrete grade for 'Moderate' exposure (RCC)M25
Key Formulas
ULS Combination 1: 1.5 DL + 1.5 IL
ULS Combination 2: 1.2 DL + 1.2 IL + 1.2 WL/EL
ULS Combination 3 (Stability): 0.9 DL + 1.5 WL/EL
SLS Combination (Characteristic): 1.0 DL + 1.0 IL + 1.0 WL/EL
Practical Notes
This standard significantly enhances and should be used in conjunction with the durability provisions of IS 456:2000.
The correct classification of exposure conditions (Table 1) at the design stage is the most critical step as it governs all subsequent durability requirements for the structure.
For critical infrastructure or structures in very aggressive environments, consider using the service life design approach outlined in Annex A, which goes beyond the basic prescriptive requirements.