# Concrete

Concrete is the material where estimating errors cost the most: a cubic metre short means a cold joint or a second small pour, a cubic metre over is money in the skip, and once it starts to set there is no rework. These tools cover the whole chain — volume from the concrete volume calculator, formwork area, cement and aggregate from the mix ratio and cement quantity calculators, then curing and striking times to plan the sequence.

The two things most often missed on site are waste and temperature. Volume results already carry a waste allowance you can tune for pumping, direct discharge or barrows, and there is a separate tool for mass concrete that estimates peak core temperature and the core-to-surface differential from placement temperature, heat of hydration and ambient conditions. Blinding, strip footings, pile caps and construction joints each have their own tool rather than being forced through a generic volume formula.

- Category page: https://jianzhujisuan.com/en/c/concrete
- Data checked: 2026-10-25

## Tools in this group

- [Concrete Volume Calculator](https://jianzhujisuan.com/en/concrete-volume): Enter length, width and thickness to get the concrete volume you need and how many truck loads that is.
- [Formwork Area Calculator](https://jianzhujisuan.com/en/formwork-area): Pick a member type, enter section and length, and get the formwork contact area plus sheet and batten estimates.
- [Concrete Mix Design Calculator](https://jianzhujisuan.com/en/concrete-mix-ratio): Work out cement, sand, gravel and water per cubic metre from the target grade and water-cement ratio.
- [Cement Quantity Calculator](https://jianzhujisuan.com/en/cement-quantity): Get total cement, bag count and the cement/fly-ash split for a given volume and grade.
- [Concrete Pour Sequencing Calculator](https://jianzhujisuan.com/en/concrete-pour-plan): Divide a slab into strips and get the volume, truck count and duration for each pour.
- [Concrete Strength Converter](https://jianzhujisuan.com/en/concrete-strength-convert): Convert between grade, MPa, psi and kgf/cm², with cube-to-cylinder correction.
- [Concrete Curing and Maturity Calculator](https://jianzhujisuan.com/en/concrete-curing): Turn curing temperature into maturity and equivalent age, and check the code minimum.
- [Concrete Saw Cut Spacing Calculator](https://jianzhujisuan.com/en/concrete-slab-joint): Joint spacing, saw depth and the sawing window from slab thickness.
- [Concrete Yield Calculator](https://jianzhujisuan.com/en/concrete-yield): Convert batch weights and density into actual yield and per-m³ contents.
- [Concrete Pumping Calculator](https://jianzhujisuan.com/en/concrete-pump): Real output, pour duration and the truck fleet needed to keep the pump fed.
- [Site Mix Adjustment Calculator](https://jianzhujisuan.com/en/concrete-water-adjust): Enter the lab mix and moisture content to get real batch weights.
- [Mass Concrete Temperature Calculator](https://jianzhujisuan.com/en/concrete-temp-control): Placement temperature, adiabatic rise and peak temperature in one step.
- [Admixture Dose Calculator](https://jianzhujisuan.com/en/concrete-additive): Percentage dose to kg per m³ and per batch, with the new w/b ratio.
- [Grout Quantity Calculator](https://jianzhujisuan.com/en/grout-quantity): Volume, weight, bags and water in one pass.
- [Shotcrete Quantity Calculator](https://jianzhujisuan.com/en/shotcrete-quantity): Back-calculate batched volume and material use from rebound.
- [Post-Cast Strip Calculator](https://jianzhujisuan.com/en/post-cast-strip): Enter strip length, width, slab thickness and waterstop size to get concrete volume plus waterstop length and weight.
- [Strip Footing Calculator](https://jianzhujisuan.com/en/strip-footing): Concrete, blinding, formwork and base area for strip footings.
- [Pile Cap Calculator](https://jianzhujisuan.com/en/pile-cap): Concrete, two-way bottom steel, formwork and blinding per cap.
- [Blinding and Cushion Calculator](https://jianzhujisuan.com/en/cushion-layer): Plan size, concrete volume and side formwork for blinding.

## Questions

### How do I calculate concrete volume?

Length × width × depth for a slab or rectangular element, π × radius² × depth for a column or pile. Break irregular shapes into simple blocks and add them. Then add waste: 1-2% for pumped concrete, 2-3% for direct discharge, 3-5% for barrow work, at the top of the range for blinding and slabs where level control is loose.

### How much cement, sand and aggregate per cubic metre?

It depends on grade and mix design. A typical C25 mix uses about 370-400 kg cement, 580-620 kg medium sand, 1250-1280 kg crushed stone and 175-185 kg water per cubic metre. Use the mix ratio calculator for your grade and cement type, then the cement quantity calculator to convert to 50 kg bags.

### When can formwork be struck?

Side forms after about 24 hours once strength reaches 1.2 MPa. Soffits depend on span: 50% of design strength up to 2 m, 75% for 2-8 m, 100% beyond 8 m — roughly 3, 7 and 28 days at 20°C. In cold weather go by companion cubes, not by the calendar.