Fluid-Filled Steel Pipe Tunnel Segment for Lower-Weight Strength

The patent employs a composite structure combining ultra-high performance concrete with gas/liquid-filled steel pipes. The steel pipes are embedded in the concrete segment, creating a composite material system that leverages the high strength-to-weight ratio of steel while maintaining the compressive strength of concrete. This composite approach provides enhanced mechanical performance without the excessive weight of traditional reinforcing ribs and secondary linings.

The patent utilizes gas-filled or liquid-filled steel pipes as structural elements. The gas or liquid under pressure acts as a strut to enhance the segment's bearing capacity and rigidity. This pneumatic/hydraulic approach replaces heavy mechanical reinforcement, providing strength while minimizing dead weight through the use of pressurized fluid columns within the steel pipe structure.

The patent divides the tunnel lining into modular segments, each containing embedded steel pipes. This segmentation allows for prefabrication of individual segments with integrated reinforcement, simplifying the overall construction process. The standardized segment design with pre-positioned steel pipes reduces on-site construction complexity compared to installing separate reinforcing ribs and secondary linings.

The patent merges the reinforcement function with the primary segment structure by embedding steel pipes directly into the concrete segment during fabrication. This integration combines the segment and reinforcement into a single unified component, eliminating the need for separate installation steps and reducing construction process complexity.

The use of ultra-high performance concrete combined with steel pipes creates a composite structure that achieves high mechanical performance with reduced material consumption. This composite approach is more cost-effective than traditional methods requiring extensive reinforcing ribs and secondary linings, as it uses materials more efficiently to achieve the required strength.

The gas/liquid-filled steel pipe system provides structural reinforcement through pressurized fluids, eliminating the need for heavy mechanical reinforcement elements. This approach reduces material costs and construction expenses while maintaining or improving structural strength compared to conventional reinforcing ribs and secondary linings.