IS 457 : 1957Code of Practice for General Construction of Plain and Reinforced Concrete for Dams and Other Massive Structures

IS 457:1957 is the code of practice for general construction of plain and reinforced concrete for dams and other massive structures — *mass concrete*: gravity dams, large rafts/blocks, thick piers, heavy foundations. It governs the construction problems that only appear at large volume — chiefly heat of hydration and thermal cracking — that IS 456 (member-scale RCC) does not address.

It sits in the mass-concrete stack:

• IS 456 — general plain & reinforced concrete (the base; IS 457 adds the *mass* provisions)
• IS 10262 — mix design (low-heat, low-cement mass mixes) · IS 269 / IS 1489 / IS 12330 — OPC / PPC / sulphate-resisting cement
• IS 12200 — water-stops · IS 6512 — design criteria for concrete gravity dams

In a thick pour the core hydrates, heats, and is restrained by the cooler skin and foundation — on cooling it cracks unless the heat is *managed at construction stage*. IS 457's provisions are about controlling that:

• Low-heat materials & lean mixes: low-heat / pozzolanic cement, lowest cement content that meets strength (strength is rarely the governing requirement in mass concrete — heat is), large/well-graded aggregate
• Lift heights & placing sequence: limited lift thickness and a placing schedule so each lift can dissipate heat before the next
• Pre-cooling / post-cooling: chilled aggregate or ice in the mix, embedded cooling pipes for large blocks; placing-temperature limits
• Contraction joints & water-stops: monolith/block joints, keyed and grouted, with water-stops for the water face
• Curing & form removal suited to slow-strength, low-heat concrete

The engineering point: in mass concrete the enemy is the temperature differential, not the 28-day cube. Design and build to keep the core-to-surface ΔT and the placing temperature within limits, or the structure cracks regardless of strength.

Scenario: a large mass-concrete block (dam monolith or very thick raft).

Step 1 — mix for heat, not strength: select low-heat or PPC cement and the minimum cement content for the (modest) required strength; use large well-graded aggregate to cut paste and heat.

Step 2 — limit the lift: restrict lift thickness and set a placing interval so each lift sheds heat before being buried by the next.

Step 3 — control placing temperature: pre-cool (chilled aggregate/ice) so concrete is placed within the temperature limit; for big blocks, circulate water through embedded cooling pipes to cap the peak core temperature and the core-to-surface ΔT.

Step 4 — joints & curing: form contraction joints with water-stops, then cure long and protect against rapid surface cooling (which spikes the differential and cracks the skin).

Govern by ΔT and placing temperature — a mass pour that 'passed the cube' but ignored Steps 1–4 will still craze and crack through.

1. Designing mass concrete like member RCC. Chasing 28-day strength with rich, high-cement mixes maximises heat — exactly wrong for mass concrete; minimise cement.

2. No placing-temperature / pre-cooling control. Placing hot concrete in a thick block guarantees a high peak and thermal cracking.

3. Lifts too thick / placed too fast. Heat can't dissipate; the core bakes and the block cracks on cooling.

4. Contraction joints / water-stops skipped or mis-detailed. Uncontrolled cracking and leakage on the water face.

5. Rapid surface cooling / poor curing. Cold water or form-strip onto a hot core spikes the surface-to-core ΔT and cracks the skin.

• IS 456 — general plain & reinforced concrete (IS 457 supplements it for mass work)
• IS 10262 — concrete mix design (low-heat, low-cement mass mixes)
• IS 269 / IS 1489 / IS 12330 — OPC / Portland-pozzolana / sulphate-resisting cement (heat & exposure)
• IS 6512 / IS 12200 — design of concrete gravity dams / PVC water-stops
• IS 383 — aggregate (large, well-graded for low paste content)

IS 457 is very old (1957) and narrow, but it remains the Indian reference for the one regime IS 456 doesn't cover — concrete thick enough that its own heat of hydration is the design problem. Modern dam/mass-concrete practice goes further (detailed thermal modelling, staged cooling-pipe schedules, often referencing ACI 207), and the design criteria live in dam codes like IS 6512 — so IS 457 is best read as the construction-control backbone, supplemented for analysis. The enduring lesson is counter-intuitive to building engineers: in mass concrete you deliberately use less, cooler, leaner concrete and obsess over lift height, placing temperature and core-to-surface ΔT — strength is the easy part; cracking from restrained thermal contraction is what actually defeats massive structures.