Composite Drainage Mesh (also known as Three-Dimensional Geosynthetic Drainage Board, Tunnel Drainage Board, and Drainage Board) is made up of a double-sided bonded plastic mesh with a geotextile that allows water permeation. It can replace traditional sand and gravel layers and is mainly used for drainage in landfill sites, road bases, and tunnel interiors.

In railway and highway infrastructure, the safety and service life of the projects are inextricably linked to their drainage systems, with geosynthetic materials being a crucial component of the drainage system.

Composite Drainage Mesh is a new type of geosynthetic drainage material. Made from high-density polyethylene (HDPE) and processed through a special extrusion molding technique, it features a three-layered structure. The central rib is rigid and arranged longitudinally to form drainage channels, while the crosswise ribs support the geotextile to prevent it from embedding in the drainage channels, maintaining excellent drainage performance even under high loads. The dual-sided bonded geotextile used in conjunction provides comprehensive "anti-filtration--drainage--breathability--protection" properties, making it an ideal drainage material currently available.