The Challenge: Durability and w/c Consistency
The water-cement ratio is one of the most critical indicators of concrete strength and durability. Fluctuating moisture in aggregates often causes discrepancies between batch plant specifications and actual conditions on site. Traditional slump tests provide only indirect information and are increasingly inadequate for modern mixes with complex admixtures. Conventional methods like the Darr process involve lengthy preparation and drying, delaying decisions and increasing labor effort. Without fast and accurate measurement of water content, the risk of cracks, spalling, and reduced corrosion protection for reinforcement rises significantly. Excess water creates capillary pores, which allow water ingress and reduce freeze-thaw resistance, leading to scaling and surface damage. Too little water leaves unhydrated cement that can swell later and cause cracking. Reliable quality control requires immediate, non-destructive analysis directly on fresh concrete to enable real-time decisions without compromising accuracy.
The Solution: Precision Moisture Analysis with TDR Technology
Accurate control of the water-cement ratio requires immediate, non-destructive measurement directly on fresh concrete. Time-Domain Reflectometry uses radar pulses to read the dielectric properties of the mix, allowing precise determination of total water content in liters per cubic meter and, with known cement content, instant calculation of the w/c ratio. Unlike the Darr method, which relies on sample preparation and drying and extends decision times, TDR provides results within minutes at the point of discharge. This enables real-time adjustments, reduces rework, and brings laboratory-grade accuracy to the job site for both high-performance and infrastructure applications.
Engineering Impact & Key Benefits
- Durability Verification: Identify and reject out-of-spec loads before placement to maintain specified exposure class requirements and long-term performance.
- Laboratory Quality in the Field: Enable reliable, on‑site quantification of water content and w/c ratio with precision comparable to lab methods, supporting stringent project requirements.
- Immediate, Non-Destructive Results: Obtain water content and w/c ratio within minutes on fresh concrete, avoiding the preparation and drying steps required by the Darr method.
- Consistent Mix Control: Manage water additions confidently and stabilize w/c across batches, reducing variability between the plant and the site.
- Productivity and Cost Efficiency: Shorten decision cycles, cut down on rework, and avoid precautionary overdosing of cement.
- Sustainability Benefits: Optimize cement usage and lower CO₂ emissions while maintaining workability and target strength.
