Building for the three rivers to promote development, carving through mountains to divert water for people's livelihood.

Recently, multiple Jintai diaphragm wall equipment have been deployed in the follow-up optimization project of the Hanjiang-Rongjiang-Lianjiang river system connection, achieving frequent successes and outstanding results. At working shafts GX13, GX01, GX02, GX10, GX07, construction machinery rumbles, and towering giant cages glide across the sky and are lowered into the trench bottom, marking the smooth progress of the retaining structures of the working shafts under construction by Jintai piling equipment. It is believed that the urgent water shortage for urban and rural domestic use in eastern Guangdong will be completely resolved soon.

△ Route map of the Eastern Guangdong Water Resources Optimization Allocation Project

According to the project manager, the water regime and hydrogeological conditions of the three-river system optimization project are complex. The Hanjiang and Rongjiang river systems have a water level difference of 10 to 20 meters. During construction, it is necessary to achieve smooth water flow connection and precise pressure regulation and flow control. The section from Yanniao Mountain to Dadan Mountain on the Chaoyang branch trunk line needs to cross a mountain about 2.5 kilometers long, mainly located in granite from the weakly weathered zone to the slightly weathered zone. The rock is hard, and the saturated uniaxial compressive strength of the rock can reach 150-250 MPa, making construction extremely difficult.

Given the outstanding performance of Jintai diaphragm wall products in domestic and international markets, the working shafts GX13, GX01, GX02, and GX10 currently under construction in the Eastern Guangdong Water Resources Optimization Allocation Project mainly use Jintai diaphragm wall products. For soft strata within 60m depth, Jintai SG70 is used for direct trenching; for hard or complex strata beyond 60m depth, Jintai SX50 double-wheel milling is used for air-lift trenching. Through years of diaphragm wall construction experience, Jintai has concluded that in complex strata, the combined process of "grab and mill" or "grab, drill and mill" can greatly improve the trenching efficiency of diaphragm walls while ensuring verticality.

△ GX02 working shaft

The GX02 working shaft is part of the section from Guxiang water diversion outlet to Guanbu water intake on the main water transmission line, and is the largest bid section of the entire project. To create a benchmark and demonstration project for the eastern Guangdong water supply project, the project adheres to the production philosophy of "strict, tight, detailed, and practical," advancing quality and safety management simultaneously, continuously optimizing the construction plan, and increasing resource investment. Ultimately, the combined construction process of "drilling + grabbing (Jintai SG70) + milling (Jintai SX40)" was adopted, and important project milestones such as the first reinforcement cage being lowered into the trench and the first adit entering the tunnel were completed.

△ GX01 working shaft

At the GX01 working shaft, Jintai SG50A completed the 10th diaphragm wall panel in 67 days, 25 days ahead of schedule. The precise closure with the first diaphragm wall panel marks that the retaining works of the main structure of GX01 working shaft are nearing completion and the main structure construction has officially begun.

△ GX13 working shaft

The GX13 working shaft is located near the Rongjiang River. The tunnel connects to the GX12# working shaft and crosses the Rongjiang River. The construction scale is large, and the hydrogeological conditions backed by the Rongjiang River are complex with strong permeability. Therefore, this project has higher requirements for process and procedure control than conventional working shafts. The GX13 working shaft adopts the combined process of "grabbing (Jintai SG70) and milling (Jintai SX50 double-wheel mill)" for construction. The diaphragm wall construction depth reaches 86.5 meters, with a thickness of 1 meter, and a total of 20 panels in phases I and II.

△ GX07 working shaft

The Hanjiang River basin is vast, the Rongjiang River is deep and scenic, and the Lianjiang River winds and turns. They are the mother rivers in the hearts of the Chaoshan people. Limited by the uneven temporal and spatial distribution of local water resources, water use conflicts are prominent. In recent years, with economic and social development, water resources have increasingly become a major bottleneck restricting the construction of eastern Guangdong. Especially in 2020 and 2021, the Hanjiang River basin and eastern Guangdong suffered consecutive rare droughts, further highlighting the resource-based and engineering-based water shortage problems in eastern Guangdong.

△ GX10 working shaft

The follow-up optimization project of the Hanjiang-Rongjiang-Lianjiang river system connection is a major livelihood water conservancy project planned and constructed by the Guangdong Provincial Party Committee and Provincial Government from a holistic perspective. The project has an estimated total investment of 10,118 million yuan, a total water transmission line length of 71.65 kilometers, and a total construction period of 40 months. The construction line needs to cross mountains, rivers, and railways multiple times, making construction extremely difficult.

After completion, it will increase the average annual water supply by 311 million cubic meters for more than 8.5 million people in eastern Guangdong, effectively improving the water supply and emergency water supply capacity in the region, and forming a sustainable water supply guarantee system with regulation between wet and dry years, multiple water source complementation, and sustainable utilization.

It is urgent to fundamentally solve the shortage of domestic water in urban and rural areas of eastern Guangdong!