Construction method for constructing the surface layer of the slope, rainwater flow control method, and method for suppressing the outflow of rainwater to the downstream area

摘要

PROBLEM TO BE SOLVED: To cause heavy rain, for example, when rainwater flows down a long slope of about 30 m to 60 m at a stretch, sediment outflow and surface collapse may occur, and rainwater exceeding the drainage capacity of the downstream area may flow down. There is. A surface layer structure 10 includes a first section member 100 and a first filling member 122. The first section member 100 is laid along the surface on the slope, and is divided into a plurality of areas (cells) 120 (first area). The first compartment member 100 has an opening. The first filling material 122 is filled in each of the plurality of regions (cells) 120. The slope surface layer is formed by at least one of changing the aperture ratio of the first section member 100 in various ways and adjusting the particle size and particle size of the first filling material 122 to change the clearance ratio and the water permeability. Adjust at least one of the flow velocity and flow rate of the flowing rainwater to suppress the outflow of rainwater that has fallen on the slope. [Selection diagram] Fig. 1