1. Lay between the foundation and the foundation to drain the water between the foundation and the foundation, block the capillary water and effectively integrate it into the edge drainage system. This structure automatically shortens the drainage path of the foundation, greatly shortens the drainage time, and can reduce the use of selected foundation materials (that is, materials with more fine materials and lower permeability). Can extend the life of the road.
2. Laying a three-dimensional composite drainage network on the base layer can prevent the fine materials of the base from entering the base layer (that is, it acts as an isolation). The aggregate base course will enter the upper part of the geonet to a limited extent. In this way, the composite geotechnical drainage network also has the potential to limit the lateral movement of the aggregate base. In this way, its role is similar to the reinforcement of the geogrid. Generally speaking, the tensile strength and rigidity of composite geo-drainage nets are better than those of many geogrids used for ground reinforcement, and this restriction will affect the supporting capacity of the ground.
3. After the road is aged and cracks are formed, most of the rainwater will enter the section. In this case, a three-dimensional composite drainage network is laid directly under the road instead of a drainable foundation. The three-dimensional composite drainage network can collect water before it enters the foundation / subbase. Moreover, a film can be wrapped on the bottom end of the three-dimensional composite drainage net to further prevent moisture from entering the foundation. For rigid road systems, this structure allows the design of roads with a higher drainage coefficient Cd. Another advantage of this structure is that it may make the concrete more hydrated (research on the extent of this advantage is ongoing). This structure can prolong the service life of the road, whether it is a rigid road or a flexible road system.
4. In northern climate conditions, laying a three-dimensional composite drainage network can help mitigate the effects of frost heave. If the freezing depth is deep, the geonet can be laid at a shallower position in the foundation to block as a capillary effect. In addition, it often needs to be replaced with a granular base layer that is not prone to frost heaving and extends downward to the freezing depth. The frost-heavy backfill soil can be directly filled on the three-dimensional composite drainage net until it reaches the foundation ground line. In this case, the system can be connected to a drainage outlet so that the groundwater level is at or below this depth. This can potentially limit the development of ice crystals, and there is no need to limit traffic loads when ice melts in spring in cold regions.