Gwayi-Shangani - Class of 2024 Field Visit

The Gwayi-Shangani Dam technical visit provided NUST Civil Engineering students with first-hand exposure to large-scale infrastructure engineering. Unlike the earth-fill Kunzvi Dam, Gwayi–Shangani is a Roller Compacted Concrete (RCC) gravity dam, offering a distinct construction and structural learning experience.

Students explored RCC technology, observing how zero-slump concrete was placed in horizontal layers and compacted using vibrating rollers. Key lessons included RCC mix design, the use of fly ash to reduce hydration heat, and thermal control measures implemented to prevent cracking and ensure long-term durability.

The gravity dam’s structural mechanics were examined, with students gaining insight into how the dam’s mass resists sliding and overturning forces. The visit also covered the 252 km Gwayi-Shangani-Bulawayo Pipeline, where students learned about pump stations, head losses, surge protection, and the use of air valves and wash-out systems.

Located at the confluence of the Gwayi and Shangani rivers, the dam served as a practical hydrology case study, highlighting catchment behaviour and sediment management. The tour concluded with an overview of the ogee spillway and stilling basin, demonstrating effective energy dissipation and downstream protection.