Concrete monitoring

Something concrete is
taking shape.

ProTest gives your team real-time concrete maturity and in-situ strength data on site — so you strike formwork, stress concrete or load structures with confidence.

Hardware, technical detail and case studies coming soon.

Concrete frames Post-tensioning Cold weather Thermal monitoring Precast Major civils
Accurate strengths
for formwork striking
Real-time
strength data vs cube lag
Auto-docs
every 10 min, as you build
BS EN compliant
accurate monitoring
How it works

From mix calibration to report — in five steps

1Calibrate mix

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

2Install sensors

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

3Temperature

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

4Analyse strength

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

5Report outputs

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

A maturity function converts that temperature-time history into an equivalent age — using an activation energy derived for your cement class, not a CEM I default.

Strength

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

A maturity curve for every cement type

PROTEST has a maturity curve for every cement type. Not one curve stretched across all of them. Real time concrete strength, built for BS EN 13670:2009.

Under British Standards, your maturity function has to be proven for the cement in use. On most maturity systems, proving it is your job. On PROTEST, it's already done. Real-time strength from the first pour.

Many systems default to Sadgrove or Nurse-Saul until you input your own maturity function calibration data.

What BS EN 13670:2009 actually asks for

BS EN 13670:2009 doesn't accept a generic maturity function. The requirement is that it must be justified against the actual cement, or cement-and-addition combination, going into the pour — not a function that happens to be widely used. That's a higher bar than it first appears — because the maturity method is really two calibrations, not one.

The strength curve

Maps maturity to MPa. Calibrated from crushed specimens cured at one temperature. UK teams do this properly, mix by mix.

The maturity function

Converts temperature history into maturity. Usually Nurse-Saul or Sadgrove in the UK. Its temperature sensitivity should reflect the cementitious combination — but is typically left on a default, and with Sadgrove cannot be adjusted at all.

The first gets calibrated diligently. The second is usually left as it comes. On UK projects the function is typically Nurse-Saul or Sadgrove, and in practice neither is usually matched to the mix. Nurse-Saul is commonly left on a default datum temperature: 0°C is the value ASTM C1074 recommends for Type I cement without admixtures, over a curing range of 0–40°C. Sadgrove carries no parameter for adapting temperature sensitivity to different mixes at all.

Here's the practical effect. The strength curve is calibrated to your mix. The temperature conversion isn't — it still assumes CEM I. Lab cubes are cured at a standard 20°C, so on a pour running close to 20°C, that barely matters. But GGBS is significantly more temperature-sensitive than CEM I — slower-gaining in cold weather, but capable of accelerating hard in a hot mass core — and a CEM I-calibrated conversion doesn't track either direction correctly. Any site condition away from that 20°C reference is where the mismatch grows — and those are exactly the pours where the strength data matters most.

Where the function does have a parameter, deriving the right value for a GGBS or PFA blend means the separate multi-temperature procedure in ASTM C1074 Appendix X1 — three water baths, mortar cubes, an exercise entirely separate from the crushing schedule. On most systems, that work is yours to do.

PROTEST holds maturity functions for each cement class. The strength relationship can also start from OTB's own strength predictions for your mix, your team supplies strength calibration data as the job runs. The difference is you're verifying a live curve from the first pour, not waiting a month to build one.

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.
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Get in touch

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

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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