Application of WIM for weight enforcement

Abstract

Brazil has recently advanced the application of Weigh-In-Motion (WIM) technology to enforce weight regulations on federal highways, targeting the issue of vehicle overloading ‒ a major contributor to road deterioration and safety risks. Two federal bodies oversee enforcement activities: the National Department of Infrastructure and Transportation (DNIT), responsible for non-concession roads, and the National Land Transport Agency (ANTT), responsible for concession roads. DNIT has implemented the Unidade Móvel Operacional (UMO) program, which integrates High-Speed WIM (HS-WIM) technology with mobile enforcement units. These units are equipped with both static portable scales (UMO-E) and dynamic portable scales (UMO-D), enabling versatile and mobile enforcement operations. The HS-WIM systems are certified by INMETRO, Brazil's metrology authority, and include infrastructure for direct enforcement such as parking areas for administrative procedures like axle rebalancing and unloading. A 2017 national procurement led to the deployment of 61 UMO units across Brazil. Concurrently, ANTT introduced Brazil’s first HS-WIM for direct enforcement under a regulatory sandbox initiative. In partnership with the Ecovias do Cerrado concessionaire on BR-364 and BR-365, the agency replaced four traditional weigh stations with HS-WIM systems. These systems allow full-speed vehicle weighing, eliminating the need for slowing or stopping. The benefits include reduced travel time, lower emissions, enhanced road safety, and cost savings in infrastructure and vehicle maintenance. HS-WIM also supports electronic enforcement of weight-related transport regulations, promoting fairness and reducing the social and environmental costs of overloaded transport. These efforts demonstrate Brazil’s commitment to modernizing freight transport regulation through innovative, scalable, and sustainable WIM technologies. The presentation will explore both DNIT’s UMO program and ANTT’s HS-WIM pilot, outlining operational insights, regulatory adaptations, and early results.