Manhole repair work

High Temperature Steam Injection Thermosetting Apparatus for Manhole Repairing and Reinforcing(HTTA method)

High Temperature Steam Injection Thermosetting Apparatus for Manhole Repairing and Reinforcing(HTTA method) (HTTA method) Manhole repair and reinforcement method using a thermal curing device for injection of high-temperature steam. Curing and curing of thermosetting polymer mortar
By minimizing time, time and expenses for the entire process are minimized, and strength reinforcement and corrosion prevention effects can be obtained. Manhole repair and reinforcement method using a thermosetting device for hot steam injection

Current status of manhole repair and reinforcement work

In general, manholes such as sewage, telecommunication, telegraph, etc. buried in the ground are mainly made of concrete, so damage, cracks, corrosion, and leakage due to weathering and aging occur over many years, resulting in leakage of wastewater, sewage, rainwater, and groundwater inflow, etc. As a result, it is becoming the main culprit of soil pollution, water pollution, and sinkholes, such as increasing the amount of sewage.

Currently, manhole repair and reinforcement works are generally constructed as manhole replacement-oriented construction by excavation. In particular, when manhole construction adjacent to downtown areas, noise and dust caused by road excavation and traffic congestion caused by the expansion of the construction occupied area have occurred. There is a problem of causing a lot of budget loss due to long-term construction due to high risk of civil complaints and various safety accidents and complicated work processes.

Lower manhole: HTTA method (non-digging)

Applicable target: Circular manhole (No. 1, No. 2, No. 3, No. 4, etc.), square manhole, etc.
Repair method: total repair, section repair, partial repair

Cross-section
Detail “A”

HTTA method

Constructability
Unlike the existing construction method, the work space is minimized as it can be constructed without large equipment.

Responsibility
Use of excellent materials with high strength chemical resistance and abrasion resistance
Integrated construction by perfect attachment of existing manhole and reinforcement
Excellent reinforcing effect due to the use of reinforcing materials (wire mesh, metal mesh)

Economics
Increase the effect of budget reduction by combining overall repair, section repair, and partial repair construction
Social indirect costs such as traffic congestion, dust, noise and disposal of waste materials are cheaper than other methods

Efficiency
Watertightness and durability are perfect, so it blocks runoff and intrusion water at the source, preventing soil contamination and Prevent economic loss with sewage treatment

Universality
Sewer, communication, telegraph, circular manhole, square manhole construction is possible
Suitable for customized construction in consideration of site conditions such as manhole damage, corrosion, leakage, stepped areas, and bent areas.
Appropriate for maintenance and prevention of defects by applying a finishing coating after construction is completed.

Features of HTTA method

The material of the manhole and the repair and reinforcement are the same to prevent lifting or cracking due to water expansion → Integrated construction due to attachment
Excellent strength reinforcement effect using reinforcing materials (wire mesh, metal mesh) → about 50% strength increase
Complete repair, section repair, partial repair combined method → Budget reduction due to selective construction of repair parts
Construction is possible even when the pipe diameter changes within the manhole.

HTTA method construction flow chart

- In the manhole before construction (CCTV and naked eye) investigation
- 1. Preliminary investigation (CCTV, naked eye)
- Sedimentary soil in the manhole, Sludge removal
- 2. Dredging and cleaning
- Fabrication of reinforcing materials using wire mesh and metal mesh
- 3. Reinforcement production
- Wire mesh and Metal mesh installation
- 4. Reinforcement manhole loading and installation
- Applying a primer to improve the adhesion of the thermosetting polymer mortar to the existing manhole
- 5. Primer application
- Plastering thermosetting polymer mortar on the existing manhole
- 6. Thermosetting polymer mortar plastering
- After plastering the thermosetting polymer mortar, it is cured for a certain time using a thermosetting device.
- 7. Curing after plastering of thermosetting polymer mortar
- After hardening and curing, Application of finishing coating
- 8. Application of finishing coating