CASE STUDY: SULTAN HAJI HASSANAL BOLKIAH HIGHWAY FLYOVER.
Installation Year:
1990s
Material Supplied:
Tensar® Uniaxial Geogrids
Project Description:
The Sultan Haji Hassanal Bolkiah (SHHB) Highway Flyover represents a landmark infrastructure development in Brunei, marking one of the region’s earliest applications of the Keystone modular block wall system in conjunction with Tensar® RE Uniaxial Geogrids. Designed to connect the main highway to key government institutions—including the Ministry of Defence (MINDEF), Ministry of Education (MOE), and Public Works Department (JKR)—this flyover plays a critical role in improving access and traffic flow in the capital.
At the heart of the project is a Mechanically Stabilized Earth (MSE) retaining wall, constructed using dry-laid Keystone pre-cast concrete blocks. These modular blocks form a near-vertical facing without the use of mortar, cranes, or temporary props, enabling rapid and efficient construction. Their flexibility also allows for seamless integration of curves and corners into the wall design, enhancing both functionality and aesthetics.
Behind the wall, Tensar® RE Uniaxial Geogrids, made from high-density polyethylene (HDPE), reinforce the soil mass. Their high tensile strength and open aperture structure ensure excellent load transfer, soil interlock, and long-term durability. This combination results in a robust, maintenance-free MSE system with a design life of up to 120 years, capable of withstanding heavy structural loads and seismic activity.
The use of locally sourced fill materials further contributed to the project’s cost-effectiveness, while the overall system provided a strong, adaptable, and sustainable solution. The SHHB Highway Flyover not only demonstrates the engineering efficiency of Keystone and Tensar technologies but also sets a benchmark for future infrastructure projects across the region.
