In urban development, many cities extensively use concrete, asphalt, and other materials to cover the ground surface, replacing the original soil topography. For public spaces such as sidewalks, outdoor parking lots, courtyards, and plazas, uniform and attractive stone slabs or impermeable bricks are commonly used. While sealing the ground surface improves traffic and road conditions and beautifies the environment, it also has significant adverse impacts on urban ecology and the climate environment.
The city has become a "man-made desert." The sealing of the ground surface and skyscrapers gradually covers the urban terrain with impermeable materials, making it difficult for water to infiltrate. Precipitation quickly becomes surface runoff, flowing into rivers or open drainage pipes, creating an ecological "man-made desert."
The city is experiencing severe "urban heat island" effects. Impermeable surfaces lack the ability to regulate the temperature and humidity of the urban terrain, resulting in rapid evaporation of rainwater, dry ground, and heavy dust pollution. Additionally, after rain, moisture evaporates quickly, air humidity is high, causing discomfort and heat, followed by an abnormal dryness, thus creating a climatic "urban heat island" effect.
In contrast, permeable paving can balance the urban ecosystem. Rainwater infiltrates the ground through permeable surfaces, rapidly increasing the water level. The permeable air also allows for the passage of "ground Qi," keeping the air warm in winter and cool in summer, and facilitating water infiltration during the rainy season and snowmelt in winter, thereby enhancing the coziness of urban living. Moreover, due to the high porosity and large surface area of permeable surfaces, they have a strong adsorption capacity for dust, reducing dust pollution and also lowering noise levels. Developed countries began researching and developing permeable paving materials in the 1970s and have applied them to courtyards, sidewalks, bike paths, public squares, outdoor parking lots, park pathways, and road medians and dividers, thereby increasing the permeable and breathable space in cities, and achieving good results in regulating the microclimate and maintaining ecological balance. After the 1990s, replacing traditional materials with permeable materials for road construction has become a common practice in urban development in developed countries. Germany, known for its environmental technology, proposed by 2010 to transform 90% of the city's road surfaces into permeable ones.
Water-permeable road surfaces hold significant importance in modern urban environments. Porous bricks offer excellent water and air permeability, allowing rainwater to quickly seep into the ground, maintain soil moisture, and improve the living conditions for urban ground plants and soil microorganisms; they alleviate the pressure on urban drainage and flood prevention; absorb moisture and heat, regulating temperature and humidity in local surface spaces; absorb noise generated by vehicle traffic; enhance the comfort and safety of vehicle travel; and the paved surfaces with porous bricks do not accumulate water after rain or become slippery after snow, ensuring safe and convenient travel for citizens.
