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Cement surface structure

Jun 20, 2019

The internal surface of the cement surface structure leaks underwater to the top surface of the base layer, and the interface water between the same surface layer and the base layer (the main source of interface water: the internal water of the cement surface layer structure, the ground water entering the interface from the edge of the road or the gap between the road surface, Groundwater, etc.), together, it flows to the roadside under the effect of gravity, flows through the porous concrete to the culvert, and then flows from the culvert to the rainwater well to realize the drainage of water inside the pavement layer.


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人妻 制服 出轨 中字在线