Real-Time Formwork Pressure Monitoring Key to Safe Concrete Construction

Vemaventuri, a sensor manufacturer, has released a press statement highlighting the importance of real-time formwork pressure monitoring in construction projects. The company emphasizes that the traditional approach of relying on calculated values for formwork pressure is insufficient, as actual conditions on-site can significantly deviate from theoretical expectations.

According to Vemaventuri, formwork engineers typically refer to standards such as DIN 18218, ACI 347R, or the applicable project standard to determine the maximum lateral pressure. These calculations involve factors like planned placement rate, concrete consistency, and ambient temperature. However, on-site realities often differ from these assumptions. Fresh concrete does not always behave as predicted, and variations in placement rate, concrete temperature, and consistency can lead to unexpected pressure on the formwork.

The company points out that self-compacting concrete (SCC) poses a particular challenge. DIN 18218:2010-01 mandates the application of full hydrostatic pressure over the entire placement height, which is often underestimated. This oversight can result in formwork failure during SCC projects.

Experimental studies, such as the one by Ding, Z. et al. (2016) published in Construction and Building Materials, have shown that relative deviations between standard-based predictions and measured pressures can range from minus 11 to plus 78 percent. Factors contributing to this uncertainty include placement rate, concrete temperature, consistency, admixtures, vibration depth, and formwork geometry.

Vemaventuri's press release underscores the need for real-time pressure monitoring to replace these assumptions with measured values. The company explains that a sensor mounted flush with the formwork surface can continuously record the actual hydrostatic load from the first contact with the concrete until the pressure has fully dropped after placement is complete. This data provides a basis for informed decisions on placement rate, ensuring safer operations and faster construction where the concrete allows it.

The company highlights several typical applications for real-time pressure monitoring: - Tall walls and columns: Sensors provide a complete pressure profile over the entire placement height. - Self-compacting concrete: Continuous monitoring ensures the capacity limit is never exceeded. - Single-sided formwork: Monitoring protects the anchors by alerting to any overload. - Bottom-up pumping: Real-time data allows safe operation despite increased hydrostatic load.

Vemaventuri claims that deployments of continuous formwork pressure monitoring can reduce placement time for comparable elements by up to 30 percent. This is achieved by safely increasing the placement rate once measured values confirm sufficient margin below the design limit. Shorter formwork occupancy times directly shorten the construction schedule and reduce construction costs without compromising safety.

The press release also mentions that the second generation of Eurocode 2 (EN 1992-1-1:2023) is set to be implemented nationally by September 2027. This new design standard relies more heavily on actual concrete properties, making real-time data even more critical.

In conclusion, Vemaventuri asserts that real-time monitoring of formwork pressure does not replace engineering expertise but shows how that expertise performs when the right data is available. The company's sensors help construction companies manage concrete placement safely and efficiently, providing a time-stamped, objective record of the load on the formwork and all corrective actions taken.