Box culverts are important facilities for urban drainage, and their normal operation is directly related to the economic development, smooth transportation, and people's safety of the city.

Box girder is a key facility for highway bridges and urban elevated bridges, which is closely related to the normal operation of the national transportation artery and the construction of the national economy.

In most areas of our country, regardless of box culverts or box girders, construction began in the 1970s. Due to prolonged external traffic loads and various environmental factors, the interior has been eroded and neglected, resulting in varying degrees and types of defects and damages. Especially the flaky peeling and local cracks on the surface layer of old concrete make reinforcement and repair very important. At present, non excavation reinforcement spray lining repair technology is widely used both domestically and internationally. The process involves hanging mesh on the inner wall of the box culvert or box beam, using fast setting, high-strength, and anti-corrosion mortar, and using XP50 box culvert specific box beam mortar spraying machine and XB70 box culvert specific mortar mixer. The inner wall surface mortar is sprayed inside to form a high adhesion, anti-seepage, compression resistance, bending resistance, crack resistance, anti-corrosion, and high-strength inner lining.

The biggest feature of the specialized spraying and mixing machine for box girder mortar is that it can directly pass through the narrow box girder culvert and box girder inspection well, and enter the interior of the box culvert and box girder for construction, truly achieving non excavation repair construction operations.

This technology has been widely applied in the repair engineering of municipal engineering, highways, water conservancy and other fields, playing an important role in accelerating the development and construction of China in the new era.

Wen Gong Hai Tao