I. Product Introduction:
Glass Fiber Reinforced Pipe (FRP) is a newly developed pipeline product in the drainage and water supply field. It can complete underground pipeline construction and installation without excavating the ground, allowing direct passage through highways, railways, rivers, and ground buildings. Thanks to its excellent corrosion resistance, light weight, smooth inner wall, high flow rate, and good adaptability to geological conditions, it has become a popular pipeline material for pipeline engineering in large and medium-sized cities.
Section 2: Product Features:
1. Lightweight (1/10th the weight of concrete pipes), with low foundation requirements, minimal demands on lifting and pipe-laying equipment, and easy construction.
2. Due to reasons such as low settlement and low uplift, pipeline alignment correction is easy.
3. Smooth inner wall, high flow rate; under a fixed flow rate, smaller pipe diameter can be used, which can reduce the overall project cost.
4. Smooth surface, low thrust, the soil's cohesion has minimal effect on the glass fiber reinforced pipe's top, no tube gripping or dead-end situations, long single push-in length, low requirements for the pushing equipment.
Section 3: Process Route:
Utilizing a 12-meter long fixed-length winding process for glass fiber reinforced plastic (GFRP) sand-filled pipes, four 3-meter-long pipe sections are produced on each mold, with intermittent sand filling as per design layers. The pure GFRP sections at each end of the pipe sections (300-800mm) are locally reinforced with glass fiber fabrics. The sections are milled and cut using specialized equipment, and once shaped and sized to specification, they can be demolded in one go. The production efficiency fully meets the required project schedule. The design and production process feature a pure GFRP and GFRP sand-filled composite reinforcement integration.
Four: Design Technology
Based on the specific application conditions of the glass fiber reinforced plastic (FRP) sand-filled pipe in the jacking pipe project, determine the design parameters such as pipe diameter, pipe material stiffness grade, soil parameters, design load (including internal pressure, vacuum, vertical static soil pressure on the pipe crown, live load of ground vehicles, and soil stacking load), etc. These parameters provide a theoretical calculation basis for the structural calculation of the FRP sand-filled pipe.
V. Structural Calculation:
Based on the selected design conditions and parameters, the structural calculations for glass fiber reinforced plastic manholes are conducted in accordance with China's national standard "Glass Fiber Reinforced Plastic Manholes" (GB/T21492-2008), "Manhole Construction Technology," and computer nonlinear finite element numerical calculations. The structural calculations of the pipe material include calculations, analyses, and checks for uplift strength, stiffness, deflection deformation, bending strength, stability analysis, seismic strength analysis, and more.
Section 6: Production Process
1. Confirm and approve the design and production plan.
2. Lining manufacturing
3. Glass fiber hoop and cross-wound inner structural layer
4. Special sanding cloth with intermittent sanding (sanding cloth continuous at pure fiberglass but stops at sanding)
5. Timely produce the pure fiberglass sections after each layer of sand-infused lamination.
6. Glass fiber hoop and cross-wound outer structural layer
7. Trim and cut to achieve uniform shapes and specified dimensions.
8. After demolding, the parts pass inspection and are then fitted with steel rings before being shipped out.
Section 7: Connection Method:
The pipe sections are connected and positioned using embedded steel sleeve rings. During pushing, glass fiber reinforced plastic resin is used for sealing. After the two pipes are joined, they serve as a water seal. A platform is machined at both ends of the pipe, allowing the steel sleeve ring to fit over the pipe end, ensuring the outer diameter of the sleeve ring matches that of the pipe. The steel sleeve ring serves as a positioning device and enhances resistance to uneven settlement. The resin mouth provides sealing, and the two pipes act as a water seal after connection. A platform is machined at both ends of the pipe to ensure the outer diameter of the sleeve ring matches the pipe's outer diameter. The steel sleeve ring functions as a positioning element and improves resistance to uneven settlement.
Section 8: Applicable Locations:
● Water supply and domestic water engineering. ● Petroleum and chemical engineering. ● Construction engineering. ● Drainage engineering. ● Electric power, metallurgy, and environmental protection engineering. Overall, FRP pipe can complete the construction and installation of underground pipelines without excavating the ground, directly crossing highways, railways, rivers, and ground buildings. This is due to the excellent properties of FRP pipes, such as corrosion resistance, lightweight, smooth inner walls, high flow rate, and good adaptability to geological conditions.
