Urban construction application of filament geotextile and other geosynthetics to play infiltration, filtration and other functions to ensure effective infiltration of rainwater into the soil, to minimize the discharge into the pipe system of rainfall; for "storage and net" measures, soil Geosynthetics such as filament fabric should be able to function as a reservoir and water purifier to ensure that rainwater is retained as effectively as possible and that sand and stone work together to purify the water and effectively store the rainwater.

For the "use, row" measures, filament geotextiles and other geosynthetics to ensure smooth drainage, good water conditions and filter conditions to ensure that not easy clogging, to achieve the goal of comprehensive utilization of green roof green roof conventional green roof combination As follows: vegetation layer + 100 ~ 150 thick modified soil + geotextile filter layer + 15 ~ 20 thick concave and convex drainage board + flexible protective layer + waterproof layer + ordinary waterproof layer +20 thick emulsion asphalt expanded perlite local slope +30 ~ 60 thick polystyrene foam board +20 thick 1: 3 cement mortar screed + reinforced concrete panel filament geotextile filter layer should ensure that rainwater infiltration process, the soil is not fine particles to be lost, while vertical Infiltration capacity should be able to be guaranteed.

Drainage plate can be used to quickly infiltrate the rainwater to the flat drainage to exclude, to ensure the effectiveness of rainwater transfer. Waterproof layer to ensure that excessive rainfall will not infringe the structural layer, to ensure the safety of the green roof. Therefore, filament geotextiles by filtration, seepage, anti-measures to ensure the green roof in the total amount of runoff control effect. Taking into account the roof is more sensitive to the load, such as sand and gravel filter material will increase the load on the roof, so green roof design, should be used to load a small, convenient laying of filament geotextile filter. Filament geotextile isolation of building materials with different physical properties. So that no loss between two or more materials is not mixed, to maintain the overall structure and function of the material, so that the load-bearing capacity of the structure to strengthen.
   
When the water flows into the coarse-grained soil layer from the fine-grained soil layer, it utilizes the good air permeability and water permeability of the acupuncture geotextile to make the water flow through it, and intercepts the soil particles, fine sand and small stones effectively to keep the soil and water engineering Stable. Filament geotextile is a good water-conducting material, it can form drainage channels in the soil structure, the excess liquid and gas within the soil structure to exclude, enhance soil tensile strength and deformation resistance, and enhance the stability of the building structure In order to improve the quality of soil, effectively disperse, transfer or decompose the concentrated stress and prevent the soil from being destroyed by external forces.