IS 3370:1965 Part 2 is the Indian Standard (BIS) for concrete structures for storage of liquids - reinforced concrete structures. This 1965 standard covers the design and detailing of reinforced concrete structures for storing liquids. It relies strictly on the Working Stress Method (WSM) to ensure uncracked sections under service loads, guaranteeing watertightness.
Covers requirements for the design and construction of reinforced concrete structures for storage of liquids.
Overview
- Status
- Current
- Usage level
- Frequently Used
- Domain
- Structural Engineering — Tanks, Silos and Storage Structures
- Type
- Code of Practice
Also on InfraLens for IS 3370
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
Practical Notes
! This 1965 version dictates that liquid-retaining faces be designed for zero cracking using the Working Stress Method. It was superseded in 2009 by a revision that allows the Limit State Method with specific crack-width controls.
! Ensure proper spacing and distribution of temperature and shrinkage reinforcement to prevent early-age thermal cracking.
! Sections thicker than 225 mm require reinforcement to be provided in two layers, one near each face.
Frequently referenced clauses
reinforced concretecementsteelwater bars
International Equivalents
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International Comparison — Coming Soon
We're adding equivalent international standards for this code.
Key Values5
Quick Reference Values
minimum reinforcement upto 100mm0.3% of gross concrete area
minimum reinforcement 450mm and above0.2% of gross concrete area
permissible tensile stress steel liquid face115 N/mm²
minimum clear cover25 mm or diameter of main bar
minimum grade of concreteM20 (for liquid retaining structures in 1965 version)
Key Formulas
Ast = T / σst — Area of steel required for pure hoop tension
fct = T / (Ac + m * Ast) — Direct tensile stress in concrete (must be less than permissible limit)
Tables & Referenced Sections
Key Tables
Table 1 - Permissible Concrete Stresses in Calculations Relating to Resistance to Cracking
Table 2 - Permissible Stresses in Steel Reinforcement
Key Clauses
Clause 3 - Permissible Stresses in Concrete and Steel
Clause 5 - Design of Liquid Retaining Structures (Working Stress Method)
Clause 6.1 - Minimum Reinforcement
Clause 6.2 - Minimum Cover to Reinforcement
Clause 8 - Jointing and Detailing
Frequently Asked Questions4
What design philosophy is used in IS 3370 Part 2: 1965?+
It uses the Working Stress Method (WSM) where the concrete section is designed to remain uncracked on the liquid-retaining face.
What is the minimum percentage of steel reinforcement required?+
0.3% of the gross cross-sectional area for sections up to 100 mm thick, reducing linearly to 0.2% for sections 450 mm thick or greater.
What is the permissible tensile stress in steel near the liquid retaining face?+
For mild steel, it is limited to 115 N/mm² to prevent excessive strain that could cause concrete cracking.
Is this code still valid?+
No, it was revised and replaced by IS 3370 (Part 2) : 2009, which introduced Limit State Design for liquid retaining structures.
QA/QC Inspection Templates
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QA/QC templates coming soon for this code.