NHRI research team was honored the titles of Advanced Collective and Advanced Individual

Full line opening of the 3,000-ton waterway from Guigang to Wuzhou in the Xijiang River (December 30, 2022)

Physical modelling of waterway improvement downstream of Changzhou Dam on the Xijiang shipping main line

On April 26, 2023, Construction Headquarters of the 3,000-ton Waterway Project from Guigang to Wuzhou in the Xijiang Shipping Main Line, Port and Navigation Development Center of Guangxi Zhuang Autonomous Region (hereinafter referred to as the “headquarters") held a summary commendation meeting. At the meeting, the headquarters highly affirmed the important scientific and technological support role in the project construction played by NHRI research team of the physical modeling of waterway improvement downstream of Changzhou Dam. The research team was honored the title of "Advanced Collective", CAO Minxiong and MA Aixing the title of "Advanced Individual of Quality Management", and CAI Guozheng, HU Ying and DENG Ya the title of "Advanced Individual".

The Xijiang shipping main line is one of the important "horizontal lines" in the national high grade waterway network with a pattern of "Four vertical lines, four horizontal lines and two networks", and an important part of the Southwest access to the sea by waterway, among which the waterway from Guigang to Wuzhou in the Xijiang golden waterway is the core one in Guangxi, and an important link between Guangxi and the Guangdong-Hong Kong-Macao Greater Bay Area. After more than four years of construction, the 3,000-ton waterway from Guigang to Wuzhou in the Xijiang shipping main line was completed on December 30, 2022, becoming the top grade inland waterway in Guangxi at present, connecting the 3,000-ton waterway in the main stream of the Pearl River in Guangdong Province, and allowing 3,000-ton ships to reach the Pearl River estuary directly from Guigang.

The 3,000-ton waterway project from Guigang to Wuzhou starts from Guigang Navigation Project on the Xijiang River and ends at the boundary of Wuzhou, with a total length of 290.5km. It was built according to the 3,000-ton waterway standard of inland rivers. The designed waterway dimension is 4.1m×90m×670m (water depth × navigation width × bending radius), and navigability guarantee rate 98%. The project was constructed in two phases. The first phase of the project was to build a 266.5km reservoir waterway from Guigang Navigation Project to Changzhou Navigation Project, which was put into trial operation in December 2021. The second phase of the project was to build a 24km natural waterway from Changzhou Navigation Project to the boundary of Wuzhou, which was put into trial operation on December 30, 2022.

The waterway from the downstream of Changzhou Dam to the boundary of Wuzhou is most significantly affected by the operation of Changzhou Navigation Project, and also an important bottleneck section in the construction of the high grade waterway of the Xijiang shipping main line. Affected by the down-cutting of the riverbed downstream of the dam, water level dropping, and the restrictions of external boundary conditions (such as bridges, wharves and anchorages), the waterway improvement and construction are more difficult. Since 2011, NHRI has carried out continuous and in-depth research on key technologies of waterway improvement in the downstream of Changzhou Navigation Project. From December 2019 to April 2021, NHRI had undertaken the "Physical Improvement Modeling of 3,000-ton Waterway Project Downstream of Changzhou Dam from Guigang to Wuzhou for the Xijiang Shipping Main Line ", and adopted the methods of data collection and analysis, riverbed evolution analysis, and a combination of fixed and movable riverbed physical modeling. The  riverbed evolution pattern and low water level drop characteristics of the Xijiang River reach between Changzhou Navigation Project and Wuzhou boundary, the navigational water flow conditions of the reach, the 3,000-ton waterway improvement scheme, the construction distribution and layout scheme and precipitation during the construction period had been studied. The research had revealed the evolution pattern and trend of the downstream riverbed near Changzhou Dam section in different periods under the influence of multiple factors, explored the non-linear drop law of the low water level near the dam downstream section under the influence of multiple factors, innovatively solved the technical difficulties of channel layout under the complex navigational environment, and proposed the improvement technical scheme of the 3,000-ton waterway downstream of Changzhou Dam with consideration of slowing down water level dropping and expanding the waterway dimension, predicting the project effect. It was the first time to carry out low water level drop tests at different stages of the construction distribution of the waterway in the bridge area near dam section and of the separation construction of the bridge area, which put forward the flow rate needed to safeguard then water depth of 2000-ton waterway during the separation construction period.

During the research process, NHRI and the headquarters closely contacted and cooperated with each other. Many webinars were held during the COVID-19 epidemic period, difficulties caused by various objective factors overcome, and the experimental work adjusted and improved to ensure that the project experiments were completed on schedule. The research results have been successfully applied in the project construction, providing important scientific and technological support and guidance for the project construction, and ensuring the regulation effect of the 3,000-ton waterway downstream of Changzhou Dam and the safety of navigation during the construction period.

At the same time, the research team of NHRI cultivated and trained talents for Wuzhou Waterway Maintenance Center of Guangxi Zhuang Autonomous Region and improved their professional and technical level related to waterway improvement.

      The awards are an affirmation of the scientific and technological support of NHRI in the construction of the 3,000-ton waterway project of the Xijiang shipping main line from Guigang to Wuzhou, and also the result of the unremitting efforts of NHRI scientific research team. NHRI will continue to further promote the scientific and technological innovation in the field of waterway transportation and make greater contributions to the development of China's transportation construction.