Trusted on major UK infrastructure projects

Know your concrete
strength. In real time.

ProTest monitors in-situ temperature and strength of hardening concrete — giving contractors the data to strike formwork earlier, reduce propping costs, and document everything automatically as you build.

Concrete frames Post-tensioning Cold weather Thermal monitoring Precast Major civils
Live — Slab C4 Active
Core temp
34.2°C
In-situ strength
28.6MPa
Maturity index
412°C·h
Strike ready in
6.2hrs
Strength gain — last 24h
Auto-report generated

PDF updated 4 mins ago · ready to export

Up to 30%
earlier formwork striking
Real-time
strength data vs cube lag
Auto-docs
every 10 min, as you build
BS EN compliant
certified monitoring
How it works

From mix calibration to report — in five steps

1Calibrate mix
2Install sensors
3Monitor temp
4Analyse strength
5Report outputs

Input mix design and materials data. ProTest calibrates the maturity model to your concrete.

Embed temperature sensors in the concrete at critical locations before the pour.

ProTest continuously records temperature data and calculates maturity in real time.

ProTest converts maturity to in-situ strength and benchmarks against project targets.

Clear reports and alerts support decisions on formwork, load, and programme.

Proven concrete science, made practical

Temperature

Sensors cast into the pour record the concrete's actual thermal history as it cures — twice an hour, continuously.

Maturity

The Arrhenius equation converts that temperature-time history into an equivalent age — the concrete's maturity.

Strength

Maturity maps to in-situ compressive strength using a calibrated curve for your specific mix — a real MPa value, on demand.

Real project — Bankside, London
17–19MPa
In-situ slab strength at 24 hours, measured by ProTest
vs
9MPa
Strength of the cube cured alongside the same slab
On-site — sensors cast into the pour
Sensor layout
Top bar
Centre slab
Bottom bar
Alongside cube
Ambient
Cube Ambient
Curing temperatures over 96 hours — Bankside slab
Temperature

The temperature graph tells the story directly: the slab reaches ~35°C at peak hydration while the cube sitting alongside cools to ambient (~5°C). Higher temperature means faster maturity gain — so the slab is far stronger at 24 hours than the cube suggests. ProTest measures the real thermal history inside the structure, not the air beside it.

Lower-carbon concrete

Knowing the real strength lets you use less cement

Roughly one tonne of CO₂ is released for every tonne of Portland cement produced. Because design uses a blanket safety factor to cover the uncertainty between cube tests and the real structure, concrete is often over-specified. Measuring true in-situ strength removes that uncertainty — opening the door to a lower strength class, less cement, and a smaller carbon footprint, without compromising structural integrity.

~1 tonne
of CO₂ per tonne of Portland cement produced
up to 21%
potential reduction in required cement in worked examples
C32/40 → C28/35
strength-class reductions demonstrated on real elements
50+ years
of established science, from Saul (1951) to the Arrhenius maturity method
BS 8110 & CIRIA R136
recognised in UK standards for formwork striking and cold-weather concreting
±7–8%
accuracy validated against drilled cores in comparative testing
ICE-funded research
OTB co-authored the Institution of Civil Engineers study on in-situ strength and embodied carbon
Why switch?

ProTest vs traditional cube testing

Capability ProTest Cube testing
High data frequency Continuous, every 10 min Single point per test
Reflects actual in-situ strength
Works accurately in cold weather
Automatic audit documentation PDF auto-generated every 10 min Manual, labour-intensive
Thermal crack risk prediction via ConTeSt integration

Built for every part of the supply chain

Contractors
Strike formwork earlier, reduce propping, and keep your programme on track with real data.
Structural engineers
Verify in-situ strength, monitor thermal gradients, and assess crack risk with confidence.
Readymixers
Validate mix performance in the field and stand out from competitors with data-backed results.
Precasters
Optimise demoulding cycles using actual strength data, reducing waste and boosting throughput.
Testing labs
Complement or replace cube testing with continuous, automatic data — less labour, more precision.
ProTest + ConTeSt — the complete thermal picture Unique to OTB Concrete

Combine ProTest sensor monitoring with OTB Concrete's ConTeSt prediction software for full thermal crack risk assessment and assured striking procedures. No other system offers this integrated approach.

Call us back

Leave your name and number and one of our engineers will call you back as soon as possible.

Get in touch

231 Vauxhall Bridge Road
London SW1V 1AD
protest@otbconcrete.com

Send a message
Temperature — Bankside slab
Centre Slab peak: 37.5°C Bottom: 37.0°C Top: 31.5°C Cube peak: 12.5°C Ambient peak: 10.0°C