Dynamics of gabion weirs and its comparison to reinforced concrete weirs

Abstract EN

Weirs are important water divergence structures.

Different types of weirs have different hydraulics on upstream as well as downstream flows, resulting in varying construction costs and different safe operation procedures.

This study presents the hydraulic comparison of two different types of weirs : reinforced concrete and gabion.

These weirs were compared using different hydraulic parameters, including downstream scouring, upstream sedimentation, discharge coefficient, water surface profile, and seepage along the weir and its foundation.

Experimental analysis was carried out to estimate scouring, discharge coefficient, and sedimentation.

Similarly, seepage analysis was performed using the SEEP/w software, while the water surface profile was drawn using HEC-RAS.

Results show that upstream sedimentation and downstream scouring were higher for concrete weirs as compared to gabion weirs due to the fact that some sediment is able to pass through the latter type.

In addition, foundation and body seepage of a gabion weir can be reduced by almost 95% when replaced with a reinforced concrete weir.

The HEC-RAS results showed that the water surface elevation for a concrete weir is much higher than the gabion.

A low discharge coefficient was observed for the concrete weir, as compared to the gabion.

To conclude, concrete weirs are more efficient in raising water level and reducing seepage.

They are also durable but need better arrangement to control scouring and sedimentation.