
Concrete mixer SQREVE-365LTS
Even mix, pour after pour.
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For 1 m³ of structural concrete (1:2:3 ratio) you need about 7.4 bags of 50 kg cement, 0.5 m³ of sand, 0.8 m³ of gravel and around 160 L of water. Use the calculator below with your volume and mix type: it gives you each material and how many batches you'll run in a 1.5-bag mixer like the SQREVG365LTS or a 2-bag one like the SQREVG550LTS.
How much of each material, in what order, and why vibrating makes the difference.
Cement, sand, gravel and water — per m³ and per mixer batch.
That's about ≈ 2 batches in the mixer.
Cement
3.7
bags (50 kg)
Sand
0.3 m³
≈ 4 wheelbarrows
Gravel
0.4 m³
≈ 6 wheelbarrows
Water
81 L
max — don't exceed
Approximate values (dry-volume method). For structural work, follow your engineer's mix design.
Calculate with dimensions, 42.5 or 50 kg bags and batches per mixer, and share the result →
The fundamental
Cement needs about 40% of its weight in water to hydrate. Anything beyond that reacts with nothing: it evaporates and leaves a pore exactly where it sat. Those pores are the strength you lost — no amount of curing or waiting brings it back.
Your mix, per cubic metre:
Water/cement ratio
0.50
28-day strength
42 MPa
≈ 6,136 psi
Normal working range
Where most structural site concrete lives.
What if you add one more bucket “so it flows”?
18 litres cost you 13% of the strength, permanently. If the mix won't flow, the answer is a plasticiser or more paste (cement AND water, keeping the ratio) — never water alone.
Strength
Falls exponentially: each extra tenth in the ratio costs about a quarter of it.
Shrinkage
More water to evaporate means more contraction — and more drying cracks.
Permeability
Pores connect. Water gets in, reaches the steel and rusts it.
Bleeding
Excess water rises and carries fines with it: a milky, weak top surface.
Estimate for well-cured concrete with class 42.5 cement. Real strength comes from 28-day cylinders — this is for deciding BEFORE the pour, not certifying after.
Practice
Your batch comes out stiff and someone shouts «add water». Go ahead: it flows better. Then break the 28-day cylinder and see what it cost.
Step by step
Don't have a mixer yet? How to choose a concrete mixer · For indoor work, the electric SQREVE-365LTS mixer
Start the mixer with part of the water and the gravel: it cleans the drum and keeps cement from sticking.
With the drum turning, add cement and sand gradually so they blend evenly.
Add the rest of the water bit by bit. More water = easier, but LESS strength. Don't overdo it.
Until you get uniform color and texture, with no lumps or dry cement balls.
Aim for a workable but not watery mix. Pour within 30–45 minutes and vibrate as you pour.
Demo
Flip the switch and see the difference in the pour.
Vibrating drives out the air trapped in the pour. Without it, you get honeycombs that weaken the structure and look bad. With the vibrator, the concrete consolidates dense, even and at its true strength.
How to vibrate properly, step by step: concrete vibration lesson
What you vibrate with


Drives out air for dense, void-free pours.
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Drives out air for dense, void-free pours.
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Drives out air for dense, void-free pours.
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Handheld electric vibrator with flexible shaft, for columns and small pours.
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Shorts
FAQ
For a 1:2:3 structural mix, about 7.4 bags of 50 kg cement, 0.5 m³ of sand, 0.8 m³ of gravel and around 160 L of water per m³. For footings (1:2:4) or subfloors (1:3:5) it changes: use this lesson's calculator with your volume.
Yes: this lesson's calculator gives you cement, sand, gravel and water per m³ and per mixer batch. Pick the mix type (subfloor, general, structural or high strength), the volume and the bags per batch.
For slabs, beams and columns, the 1:2:3 structural mix (cement : sand : gravel), around 210 kg/cm². For footings and walls, 1:2:4 (~180 kg/cm²); for non-loaded subfloors, 1:3:5 (~140 kg/cm²).
First part of the water and the gravel, then cement and sand with the drum turning, and finally the rest of the water bit by bit. Mix 2–3 minutes until the color is even and pour within 30–45 minutes.
No: extra water evaporates and leaves pores that cost strength for good. If it won't flow, use a plasticiser, raise cement and water together, or consolidate with a vibrator.
For medium pours a 1.5-bag (365 L) mixer is enough: the petrol SQREVG365LTS, or the electric SQREVE-365LTS for indoor or noise-restricted sites. For big pours, the 2-bag SQREVG550LTS (550 L) needs fewer batches.
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