Void and white paste detection in cement grouted external cables and external prestressing ducts
Sixense EverScan system is an advanced diagnostic solution specifically developed to assess the internal condition of cement-grouted external prestressing cables and ducts.
These cables play a critical role in reinforcing structures such as bridges and large civil engineering works, yet unlike internal tendons, they are only anchored at their ends and remain unbonded along their free length. This makes them particularly vulnerable: if deterioration occurs within the duct—such as voids, air pockets, or zones filled with improperly mixed grout (often referred to as “white paste”) — the cable can lose its ability to transfer loads effectively.
In such cases, failure can occur suddenly and without visible external warning, significantly compromising the structural integrity of the asset.
EverScan, developed in collaboration with the University Gustave Eiffel, addresses this challenge through a non-destructive testing approach that enables detailed internal inspection of these critical elements.
The system works by deploying specialized sensors along the length of the cable or duct, capturing high-resolution data that reflects variations in material density and composition within the grouted environment. Through advanced signal processing and interpretation algorithms, E-Scan can accurately identify anomalies such as voids, segregation of grout components, or insufficient filling. These defects are mapped along the cable, providing engineers with a clear and precise understanding of where potential weaknesses are located, even in otherwise inaccessible sections.
The applications of EverScan are particularly valuable in the inspection, maintenance, and lifecycle management of infrastructure assets. By detecting early-stage defects that could lead to corrosion or mechanical failure, asset owners and engineers can proactively plan targeted interventions rather than relying on reactive repairs. This not only enhances safety but also reduces long-term maintenance costs and operational disruptions.
EverScan is widely applicable in bridges, post-tensioned structures, and other systems that rely on external prestressing, offering a reliable way to ensure continued performance and durability.
Ultimately, EverScan transforms hidden structural risks into actionable insights, supporting more informed, data-driven asset management strategies.
