What is the paving process of permeable brick?

First, when laying, hang lines at the four corners of the grid, and lay permeable bricks every other meter around the grid. After laying around the permeable brick, pay off along the horizontal direction of the permeable brick design, put a line every meter, hang it in the position of the longitudinal permeable brick, and lay it in different warehouses.

2. Before laying, the permeable brick should be wet, but the surface can not have moisture. The paving thickness of fine stone mixed soil is 0.5 ~ 1 cm higher than the design requirement. Due to the limited cohesiveness of fine stone concrete (less slurry), after paving the fine stone concrete, the bottom of the permeable brick shall be dipped in cement slurry with a mortar ratio of 0.4 ~ 0.5, and plastic shall be inserted at the joints on both sides of the permeable brick for 5mm, and the permeable brick shall be directly hammered with a rubber hammer to connect its two corners with the brick.

3. After surviving for 24 hours, spray water for maintenance for 2-3 days. During this period, the paved permeable brick shall not be disturbed. Medium-fine sand must be dry sand, and the silt content is below 1%, so it needs to be swept for many times. Immediately after each sweep, spray water to ensure that the sand can fill the gap until the sand does not sink after spraying water.

Permeable brick originated in Holland. In the process of building a city around the sea, it is found that the ground after draining seawater will cause continuous land subsidence because it can not contact with water for a long time. Once the dams on the coastline are washed away, the seawater will quickly rush to cities much lower than the sea level and flood the whole coastal cities. In order to prevent the ground from sinking, the Dutch made a small pavement brick with a length of 200mm, a width of 100mm and a height of 50 mm to 60 mm, leaving a gap of 2mm between the bricks. In this way, when it rains, the rain will seep into the ground from the gaps between the bricks. This is the later famous Dutch brick.