How we supply it: We do not run a batching plant. RMC is arranged through partner plants that quote, batch, deliver and bill it and pay us a referral commission. We pass on your grade, volume, pump need and date; for the smaller pours you mix on site, we deliver the 20 mm jalli and M-Sand by the tipper load.
In one line: Ready-mix concrete is concrete batched by weight at a central plant to a specified grade and delivered to site in a revolving transit mixer, as covered by IS 4926.
Booking a pour, step by step
- Take the grade, slump and any admixture from your structural drawing or engineer.
- Work out the volume (see below) and add 2–3% for spillage and uneven formwork.
- Choose how it will be placed: boom pump, line pump or direct chute; that decides the slump and the crew.
- Book two to three days ahead with a start time, and agree the gap between trucks so the pour face stays live.
- The day before, get centering, cover blocks and steel inspected; arrange vibrators and curing water.
- On the day, check each delivery ticket before discharge and cast cubes from the first trucks.
What RMC is
Ready-mix concrete is concrete batched by weight at a central plant to a specified grade and delivered to site in a revolving transit mixer, as covered by IS 4926. The mix is designed to IS 10262 and accepted on IS 456 sampling rules.
Weigh-batching is the point. Site mixing measures sand and jalli by the head-pan, so two batches of the same nominal mix can differ noticeably.
Grades for a house
| Grade | Typical use | Note |
|---|---|---|
| M10–M15 (PCC) | Levelling bed under footings, floor base | Usually site-mixed, not RMC |
| M20 | RCC in mild exposure | Lowest grade IS 456 allows for RCC |
| M25 | RCC exposed to rain, most footings | A common choice for house frames |
| M30 | Coastal exposure, sumps, heavier members | Design mix with tight water control |
RMC or site-mixed concrete?
| Point | Ready-mix | Site-mixed |
|---|---|---|
| Mix control | Weigh-batched with plant records | Volume-batched by head-pan |
| Time for a roof slab | Hours, with a pump | A full day or more |
| Crew | Small | Large |
| Sensible minimum | One mixer load, about 6 m³ | Any quantity |
| Access | Needs room for mixer and pump | Works in tight lanes |
| Cold-joint risk on big slabs | Low with steady trucks | Higher |
Volume for slab, beams and columns
Typical estimate: . Take dimensions from your drawing and add 2–3% for spillage.
- Slab: 1,000 sq ft (92.9 m²) × 125 mm = 11.6 m³, about 12 m³ with allowance
- Beams: 230 × 300 mm below slab, 60 m total = 4.1 m³
- Columns: 230 × 300 mm × 3 m × 12 columns = 2.5 m³
- One cubic metre of concrete weighs about 2.4 tonnes
Checks at the mixer chute
- Read the delivery ticket: grade, quantity, batching time, slump, admixture and truck number.
- Compare batching time with arrival time; a long gap without a retarder is a reason to call the plant before discharge.
- Run a slump test on the first truck and whenever a load looks different.
- Cast cubes: IS 456 asks for one sample for 1–5 m³, two for 6–15 m³ and three for 16–30 m³, each of three cubes for 28-day testing.
- Refuse water added at site to loosen the mix unless the plant's engineer approves an admixture dose.
- Count trucks and volumes against the order.
Placing and curing
- Place and compact continuously; plan the sequence so no edge sits idle.
- Keep a needle vibrator running and a spare on standby.
- Start curing once the surface can take it: pond slabs for at least 7 days with OPC and 10 days with PPC or PSC.
- Do not let anyone add water to the pump hopper.
Pour-day mistakes
- Ordering short: a missing cubic metre means a cold joint or a hurried site-mix patch.
- Booking before checking that a mixer can turn into your street.
- Accepting a ticket with the wrong grade because the truck is already there.
- Skipping cube casting.
- Pouring onto centering whose props were not checked the day before.