Temporary Precast Concrete Barriers for Safe Tunnels and Bridges

Ensuring the safety of all road users is a top priority, particularly on bridges and in tunnels, where risks and spatial constraints are especially pronounced. While these structures are essential components of global transport systems, they also act as bottlenecks and represent some of the most sensitive points within road networks.

When construction or maintenance work becomes necessary in such environments, limited space and continuous traffic significantly amplify safety challenges for both workers and road users. Temporary barrier systems used under these conditions must therefore deliver reliable protection and proven crash performance, while occupying minimal space and enabling efficient installation to keep traffic disruption to a minimum.

Deploying effective longitudinal barrier systems in tunnels and on bridges presents unique challenges. Traditional safety barriers often require more space than is available in these confined environments, and infrastructure constraints may prevent permanent anchoring solutions. At the same time, maintenance or construction activities cannot accommodate extended lane closures or lengthy installation periods, making flexibility and speed essential. In addition, safety systems must be scalable to address a wide range of impact conditions, from passenger vehicles to heavy trucks.

To address these challenges, REBLOC developed a temporary longitudinal barrier system engineered specifically for confined work zones. The REBLOC 80SAH represents a breakthrough in temporary longitudinal barrier technology. Eligible for federal reimbursement at both MASH Test Levels TL3 and TL4, the system addresses critical space and flexibility requirements in highway work zones - particularly in high-risk, space-constrained environments such as tunnels and bridges.

How the System Performs

REBLOC 80SAH is a MASH-tested longitudinal barrier system designed to prevent errant vehicles from leaving the roadway. In the event of a collision, the system absorbs kinetic energy, decelerates the vehicle in a controlled manner, and safely redirects it back onto the roadway, thereby reducing the risk of severe damage and injury.

The precast concrete barrier features a fully integrated, proprietary coupling system that requires no auxiliary components, ensuring fast installation and consistent performance. Using 40-ft modular precast concrete elements, deployment is both quick and straightforward. The REBLOC 80SAH offers one of the narrowest footprints and fastest installation rates in the industry. It can be deployed as a median barrier or along shoulders to protect workers, shield roadside hazards, and secure drop-offs on both asphalt and concrete pavements.

Advantages for Constrained Work Zones

A defining characteristic of the REBLOC 80SAH is its exceptionally narrow 11¾-inch footprint, making it particularly well suited for tunnels and bridges, where space is limited and safety risks are high. The system can be installed as either a free-standing or anchored barrier, providing flexibility for temporary applications.

Its fully integrated coupling system forms a continuous steel tension element along the entire barrier length, resulting in outstanding impact performance with a TL3 dynamic deflection of just 11 inches. Weighing only 183 lbs/ft, up to 240 feet of barrier can be transported per truckload, reducing the number of deliveries required and significantly shortening installation and removal times.

Benefits to Work Zone Safety and Operations

By minimizing barrier width while providing MASH TL3 and TL4 performance, the REBLOC 80SAH helps preserve valuable roadway space and improves traffic flow through work zones. Rapid, weather-independent deployment reduces the duration of road closures and minimizes worker exposure during installation and removal. Low dynamic deflection further enhances safety for both workers and road users, particularly in high-risk, constrained environments. Overall, the system delivers superior safety, operational efficiency, and cost-effectiveness compared to conventional barrier solutions.

As agencies and contractors continue to prioritize work zone safety under increasingly complex roadway conditions, temporary barrier systems that combine high crash performance with efficient deployment play a critical role. In tunnels and on bridges - where space and time are limited - solutions specifically designed for these constraints can significantly reduce risk and improve overall work zone safety outcomes.

Author:
REBLOC Inc.
1000 N West Street 
Wilmington, DE 19801
www.rebloc.com
[email protected]