Konstantin Gorkov, Head of the Engineering and Technical Centre of TechPolymer Group
Abstract. An innovative technology for the repair and protection of culverts is presented, based on the use of a polymer protective liner. The technology’s advantages, requirements and application procedure are outlined.
The PipeArm technology developed by specialists of the Russian TECHPOLYMER Group enables culverts to be restored, extending the service life of structures by up to 50 years, eliminating existing defects and preventing new ones, including failure of joints between sections, corrosion or destruction of the concrete protective layer, exposure and corrosion of reinforcement, the formation and development of longitudinal and transverse cracks, settlement and separation of sections.
Work using the PipeArm technology does not require traffic closures, allocation of land for the construction and subsequent remediation of temporary bypass roads, dismantling of embankments and road surfaces, or dismantling of culvert structures, significantly reducing time and material costs. This technology is applicable to all structures of small culverts (metal/concrete).
To optimise the costs of repairing and reconstructing federal and regional roads, as well as other structures, the TECHPOLYMER Group offers a modern alternative method for restoring culverts.
Technology description
The PipeArm culvert rehabilitation technology restores the load-bearing capacity of the structure by concreting over permanent polymer formwork and consists of three interconnected technical solutions:
- installation of a reinforcement cage inside the pipe;
- installation of a polymer protective liner inside the pipe body;
- monolithic integration of the structure: filling the space between the pipe body and the polymer liner with a high-strength mix.
The polymer liner is made of high-density polyethylene (ТУ 22.29.29-019-56910145-2019). It has a smooth surface with a low roughness coefficient on one side and special anchoring elements on the other for securing it in the monolithic concrete layer.
The reinforcement cage consists of longitudinal steel reinforcement with transverse winding made of composite polymer reinforcement. The cage is manufactured at the work site and secured to the walls of the pipe being rehabilitated.
The space between the polymer liner and the pipe is filled with a special high-strength, non-shrink, self-compacting mix (СУБС) based on a mineral binder. This ensures uniform filling of all voids and reliably connects the reinforcement cage with the anchoring elements of the polymer liner.
This integrates the structure into a single unit with high load-bearing capacity and low hydraulic resistance, resistant to adverse environmental effects, while preserving the maximum useful cross-section of the culvert. The slight reduction in the opening of the culvert is offset by the low roughness coefficient of the polymer liner, preserving the structure’s high flow capacity.
Implementation of the PipeArm technology
The technology was developed with reference to ODM 218.3.046 “Recommendations on the technology for repairing culverts using composite materials” and GOST R 59200, and has repeatedly demonstrated its effectiveness in practice.
Photo: culvert before repair
In 2021, a culvert on the A-310 Chelyabinsk–Troitsk–border with the Republic of Kazakhstan road was repaired. The structure is a reinforced-concrete three-cell circular culvert with an opening diameter of 1.5 m; the length of each pipe opening is 34.16 m, and the total structure length is 102.48 m. The work was carried out without restricting traffic flow on the road.
The total duration of the work was 57 calendar days.
As a result, the customer received an artificial culvert structure with its flow capacity preserved, a finished aesthetic appearance, and environmentally safe and durable performance.
During construction supervision and acceptance of the completed facility, it was confirmed that all stages of the PipeArm technology had been completed in full compliance with the design documentation. Tests, including those using destructive inspection methods, demonstrated the high quality of the work and materials used.
Technology advantages
The innovative PipeArm technology, developed specifically for repairing and restoring culverts, offers clear advantages:
- Eliminates structural damage, prevents the development of new defects and/or further structural failure;
- Extends the service life of the structure by up to 50 years or more;
- Reduces operating costs, as well as the estimated cost and duration of repair work;
- Environmentally safe;
- Provides the structure with an aesthetic appearance.
The technology can be applied across the construction industry, to structures of different hazard classes and in various natural and climatic conditions. Specialists of the TECHPOLYMER Group manufacture materials and structures for implementing the PipeArm technology, develop design and estimate documentation for projects, advise construction and repair organisations, and provide on-site support.
Photo: culvert after repair
Project passport: “Repair of a circular reinforced-concrete culvert using the PipeArm technology at km 135+496 of the A-310 Chelyabinsk–Troitsk–border with the Republic of Kazakhstan road”
Customer: FKU UPDROR Yuzhny Ural
Facility: Reinforced-concrete three-cell culvert, 1.5 m in diameter, at km 135+496
Total structure length: 102.5 m
Start of work: 13 July 2021
Completion of work: 05 September 2021
Cost of work including materials: RUB 8 735 825,85 including VAT
