Dr. Shameem Ahmed
Department Of Civil Engineering
Bangladesh University of Engineering and Technology (BUET)
shameemahmed@ce.buet.ac.bd;
Abstract
This study aligns with key documents outlining the expansion of inland waterway facilities
in the Xijiang River Water System, focusing on reconstructing the locks at the Mashi
Hydropower Station to accommodate a 2 × 1000-ton push fleet and 1500-ton single ships.
The project proposes lock chamber dimensions of 190m × 23m × 4.8m, a maximum design
head of 22m, and an annual downstream throughput capacity of 780 million tons. A 1:25
scale physical model was used to analyze hydraulic characteristics of lock filling and
drainage, ship berthing conditions, and flow patterns within the water conveyance system.
Results indicate that with a 7-minute continuous valve opening (tv = 7min), the water
transfer time meets design requirements. Energy dissipation was enhanced by adding a
0.8cm dissipation can spaced 1.2m from the branch hole, ensuring maximum bollard forces
(16.96 kN longitudinal, 11.20 kN transverse) remain within limits. Pressure tests revealed
the lowest instantaneous pressure near the valve gate was 1.25 m water column, and at the
slope rise, it was -0.26 m water column, meeting corridor specifications. Adjustments to the
inlet elevation and area eliminated adverse hydraulic phenomena under maximum head
conditions, while vortex issues at the lowest navigable water levels were mitigated by
extending valve opening to 8 minutes.
Keywords: Ship lock, Filling and emptying system, Inland waterway transportation, Liujiang
River Basin, Navigation infrastructure
Citation
Dr. Shameem Ahmed. (2025). Hydraulic Design for Mashi Hydropower Station Lock Expansion Using a 1:25 Scale Physical Model. Zenodo. https://doi.org/10.5281/zenodo.14623743