State Grid Hubei Electric Power Carries out Full-Scale Test of Inorganic High-Performance Composite Cable Jacking Pipe

January 30th, a State Grid science and technology project, titled "Design and Process Research of Inorganic High-Performance Fiber Composite Cable Pipe Jacking," led by State Grid Hubei Electric Power, conducted full-scale tests of inorganic high-performance fiber composite cable pipe jacking at Longquan Pipeline (Zhengzhou Branch). Participants included State Grid Hubei Electric Power, China Electric Power Research Institute, Hubei Electric Power Design Institute, and Guangdong Gaiteqi New Material Technology Co., Ltd.

The cable jacking pipe used in this test is the first large-diameter cable jacking pipe in China made of high-performance fiber composite materials (UHPC). By incorporating materials such as nano-silicon, nano-calcium, and steel fiber, the pipe has the advantages of high strength, crack resistance, and good impermeability. To ensure the smooth progress of the test, State Grid Hubei Electric Power organized several expert seminars to clarify the design parameters of the test pipe segments and developed two sets of radial and one set of axial compression test plans. The pipe segment used in this radial test had an outer diameter of 2.86m and a wall thickness of 180mm. The crack load of the pipe segment reached 210 kN/m and the ultimate load was 410kN/m, reaching the level of ordinary C50 concrete Class III pipe. In particular, the ultimate load was approximately 25% higher than that of Class III pipe, verifying the high strength and high crack resistance of the UHPC cable jacking pipe and providing scientific support for its practical application in subsequent projects. After using UHPC material, the 180mm wall thickness of the cable jacking pipe can be reduced by 21.7% compared to the conventional 230mm wall thickness, the steel bar usage is reduced by 30%, the weight is reduced by 20%, and the space inside the pipe is increased by 8%, which provides favorable conditions for optimizing construction and cable layout and reflects good application prospects.

Next, State Grid Hubei Electric Power will continue to optimize UHPC cable jacking pipe design, conduct water-sealing tests on flexible joints, and conduct mechanical property testing based on the test results. The company will also fully promote the implementation of the State Grid Guide project findings in its projects, with plans to deploy UHPC cable jacking pipes in the 220 kV Wuhan Dengxi Project in June. This technology significantly reduces pipe segment wall thickness, lowers unit weight, and increases cross-sectional utilization, improving the quality and efficiency of cable channel construction and promoting high-quality development of power grid infrastructure.