According to the statistical survey of the articles published by China Economic Weekly, among the list of 30 pilot sponge cities in 2015 and 2016, 19 floods occurred in summer, accounting for up to 63%. As early as last year, China officially launched the nationwide construction of sponge cities on a trial basis. In the "Guiding Opinions on Promoting the Construction of Sponge City", we proposed a construction policy that will absorb and use 70% of the rainfall on the spot. The timetable is that by 2020, more than 20% of the urban built-up area will meet the policy requirements, and by 2030, more than 80% of the area will meet the policy requirements. The policy direction is very clear and will drive the overall development of the permeable brick market. Many manufacturers and enterprises are rushing to produce and expand the inventory of permeable bricks to meet the huge potential market demand, and the automatic permeable brick presses have also become popular.
However, relative to the overall macro policy, permeable bricks are only in a micro-orientation, but they are also an essential micro-link in the construction of sponge cities. The wind direction of the policy is very clear, but we must recognize one problem. This wind is lacking the standards for the use of permeable bricks. Sponge city is a new concept. No matter it is local or central, it is now crossing the river by feeling the stones. The top design of the center does not clearly define some check targets, such as how to check the built-up and non-built-up areas in the pilot area.
So who will supervise and formulate the standards for the use of permeable bricks? Who will supervise the pavement process? Can the consistent permeable bricks' permeable function standards be satisfied with the requirements of different urban climatic conditions? Who will be responsible if there is a problem? The problem seems to have been collectively ignored in the downwind of policy. The vast majority of manufacturers did not pass field investigations, and their understanding of the permeable brick market remained at "just produce and sell." The lack of cooperative municipal pavement construction and sales ideas is also one of the flaws. Even in a micro-position, sales and production must have a systematic induction of market thinking that combines urban functions. It is reported that the permeable function of permeable bricks can be divided into 0.1 mm / second, 0.5 mm / second, 1 mm / second, etc. The larger the number of millimeters per second, the better the permeable function. The performance of the water permeability function depends to a large extent on the concrete laid under the bricks. However, appropriate pavement roads use low-permeability concrete. In this way, the permeability of the bricks is better, and a lot of surface water is also used. No direct access to the soil.
Now there are media statistics that 19 of the 30 sponge cities still suffer from waterlogging, indicating that the results of permeable bricks in the "big test" have not reached the expected results. This will inevitably have an impact on the producers of permeable bricks. Setting the production standards for permeable bricks will be on the agenda. The wind will not stop, but the direction of the wind will change, and a large number of "bricks" will be broken.
"You can't say that the Sponge City pilot failed because of the flood," said Yu Kongjian, a member of the Academy of Arts and Sciences and the dean of the School of Architecture and Landscape Design at Peking University. Similarly, it cannot be said that flooding is the failure of permeable bricks. The key is that we have to see the thinking of permeable bricks under the flooding problem. Instead of facing a passive situation, it is better to change our active habits. A related geological engineering builder said: "Although permeable bricks originated from abroad and their technical level has been properly seasoned, in fact, Europe and the United States and other places not only use permeable bricks, but choose to set up a complete rainwater collection system. Ground infiltration is just one aspect. It is more about setting up water storage equipment on the roof and around the square, and connecting it with water systems such as irrigation and car washing services, so that rainwater can be recycled. "