The Introduction of the Sponge City Concept

China is currently in a phase of rapid urbanization and development, with significant achievements in urban construction. However, alongside this rapid urban growth, many cities...The "man vs. water" conflict is intensifying, with frequent flooding disasters, deteriorating water environments, and water shortages highlighting a series of issues. Statistics show that 60% of China's cities have experienced internal flooding, turning urban flooding into a satirical sight. Data indicates that in over 200 medium-sized cities across the country, two-thirds have faced the "rain always leads to flooding" phenomenon. The root cause is the destruction of water ecosystems and the neglect of their protection. From July 21 to 22, 2012, around 8 AM, Beijing and its surrounding areas were hit by heavy rainfall in years, causing severe urban flooding, affecting 124,000 people, disrupting roads to Fangshan, Tongzhou, and Huairou, paralyzing urban traffic for several days, leaving nearly 80,000 passengers stranded at the capital airport, resulting in 79 deaths, 7 missing, and 43,000 people being urgently relocated, with economic losses nearing 10 billion yuan—a惨痛的教训.
General SecretaryOn December 12, 2013, at the Central Urbanization Conference, the concept of sponge city was proposed as a new urban development philosophy. It inherits the profound thoughts and cultural heritage of ancient Chinese urban construction, which emphasized "the unity of heaven and man, and the law of nature." It represents a new systematic solution for China's urban development issues such as water safety, water environment, and water resources. It is of great significance in resolving the increasingly prominent contradiction between humans and water, and in reconstructing a harmonious relationship between humans and water.
March 2015, the national program commenced..A batch of申报 and selection work for pilot sponge city projects16 cities have been selected. In 2016, an additional 14 cities were included in the second batch of national pilot "sponge cities." Sponge cities refer to urban areas that exhibit "resilience" like sponges, adapting to environmental changes and responding to natural disasters. They absorb and store rainwater during rainfall, then release and utilize the stored water during droughts, creating a beneficial cycle of "precipitation - runoff - infiltration - return."

Sponge City System Essential Component – Permeable Pavers

The concept of Sponge City construction is first and foremost a system, not just a product or service in isolation. A representative of substantial application in Sponge City materials.——The permeable bricks exhibit excellent features such as water permeability, compressive strength, wear resistance, anti-slip properties, and environmental-friendly, colorful, aesthetically pleasing designs. They have become "breathing" urban landscape pavements and effectively alleviate the urban heat island effect, preventing city roads from overheating. Under the new circumstances, sponge cities represent an innovative approach to promoting green building construction, low-carbon urban development, and the formation of smart cities. It is a perfect integration of modern green technology with social, environmental, and cultural factors in the context of the new era.
Porous bricks, originally known as Dutch bricks, originated in the Netherlands. During the Dutch process of reclaiming land for cities, they discovered that the ground would continually sink over time due to a lack of moisture after seawater was drained. Once the sea dykes were breached, seawater would rush into the city, which was much lower than sea level, and flood the entire coastal city. To prevent further ground sinking, the Dutch created small paving bricks for street surfaces, leaving gaps between the bricks to allow for water permeation.2-millimeter gaps. During rain, water would seep through the bricks and into the ground, which later became famously known as the Dutch bricks.
The Evolution of Permeable Pavers

The Origin of Dutch Bricks. With its low-lying terrain and extensive shallow beaches, the Netherlands boasts fertile farmlands. In the process of reclaiming land from the sea, the permeable properties of bricks were highlighted, leading to the invention of the iconic Dutch brick.

In the 1960s, the Schub洛克 Company in the United States modernized the Dutch brick. They invented a pavement tile with a strong moisture-absorbing capability, known as the Schub洛克 pavement tile.

③ With technological advancements and the expansion of permeable concrete applications, the material has been researched and utilized in the U.S. since the late 1970s and 1980s. Many countries are actively promoting its widespread adoption. For instance, Germany anticipates transforming 90% of its roads to permeable concrete within a short period, altering the past detrimental ground coverings that destroyed urban ecosystems, thereby achieving significant social benefits from permeable concrete roadways.

④ In the 1990s, Chinese technicians, based on the fundamental principles of Shuboluo brick, invented a type of paving brick. The bricks are filled with permeable voids, made from sand and gravel as raw materials, mixed with concrete and plasticizer, offering excellent water absorption and permeability. This innovation is significant in reducing ground water accumulation in urban areas and improving the city's natural environment. It is known as the "Dutch brick" in China, or bread brick.

The excellent permeability and the ability to regulate urban temperature and humidity have led to the rapid development of permeable bricks in China as part of the national "Sponge City" initiative. These bricks are widely used in urban road surfaces, biological parks, city squares, subway stations, and underground parking lots. The production line equipment and technical capabilities are also continuously improving, with higher permeability rates and a wider variety of specifications and colors.
2. Current classifications of permeable bricks commonly used:
① Standard Permeable Concrete Pavers are porous concrete materials made from ordinary crushed stones, molded into pavers for general street pedestrian sidewalks and plazas, being a standard product.
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② The Colorstone Composite Concrete Porous Pavers feature a surface layer made of natural colored granite, marble, and modified epoxy resin, which is then pressed and compounded with a polymer fiber-porous concrete base. The product boasts a luxurious appearance with natural colors and a texture similar to stone. It is primarily used in upscale commercial areas, large squares, hotel parking lots, and high-end residential complexes..Original text: 档别墅小区等场所。 Translation: High-end villa communities and other locations.
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③ Porous Ceramic Paver: Made from slag and recycled ceramics, this paver undergoes secondary blending, single-stage high-pressure molding, and is fired at 1300°C, ensuring its porousness, water retention, and high strength. The paver's porosity reaches 25%, allowing it to permeate 60kg of water per minute, with a water retention capacity of approximately 12L per square meter under normal conditions. It is widely used for paving on sidewalks, squares, gardens, courtyards, and other similar areas.
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④ Eco-sand permeable bricks, utilizing the permeable principle of "destroying the surface tension of water," effectively address the technical challenges of traditional permeable materials being easily blocked by dust through their pores, as well as the contradictions between "permeability and strength" and "permeability and water retention." These bricks are formed without sintering at room temperature and are a new type of eco-friendly material produced from wind-blown sand in deserts. The application of industrial and mining by-products, micro-fine materials, and other eco-friendly and energy-saving materials brings new development and innovation to eco-sand permeable bricks. The bricks are made in two stages, with the surface layer of the second pressing offering a more diverse range of colors.

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3. The Functions and Advantages of Permeable Pavers
Outstanding breathability and water permeability

Natural precipitation can quickly penetrate the surface, timely replenishing groundwater resources. Harnessing the soil's advantage in regulating urban temperature and humidity, it maintains the ecological balance of the city's surface. It ensures rainwater does not accumulate on roads, improving both the safety and comfort of vehicle travel and pedestrian movement.
High Value for Money

The imitation stone permeable bricks can highly replicate the color and texture of natural stone, with even greater consistency than the real thing. For instance, in the Shaoxing market, the information price for granite slabs is approximately...The price for permeable bricks in the Shaoxing market is approximately 190 yuan per square meter, with the delivery price to the construction site around 130 yuan per square meter. Due to the lack of complete price information for permeable bricks in the Shaoxing market, the price in Hangzhou as shown in the following image, from June, is used as a reference. The price for imitating stone permeable bricks is only 108 yuan per square meter, with the market supply price at 80 yuan per square meter, which can save over 1/3 of the construction cost.
Outstanding performance and technical specifications

Large-scale block production line produces permeable bricks, formed through high-pressure molding (the vibration force of the molding process reaches)Our product, with a weight of over 15 tons, boasts compressive and flexural strengths exceeding industry standards. The compressive strength reaches over 45MPA, and the flexural strength is above 4.0MPA, ensuring vehicle traffic after installation. Anti-slip and wear-resistant: Compared to natural materials, the anti-slip index BPN is no less than 60 (stone is 32), demonstrating superior anti-slip and wear-resistant properties.
④ Variety in patterns and specifications

Our customizable permeable pavers, available in various sizes, colors, and textures, offer a rich palette of durable options, perfect for creating elegant urban landscape roads.
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Green and Environmental Friendly

Absorbing dust and noise generated by vehicle travel, we create a quiet and comfortable traffic environment. Additionally, our solutions effectively mitigate the urban heat island effect, with the surface temperatures of paved stone and permeable bricks differing significantly during the hot summer months.Approximately 5 degrees.

Porous Brick Construction and Maintenance

1. Permeable paver installation
The installation of permeable pavers is similar to that of stone paving. To allow the water absorbed by the permeable pavers to seep into the ground, the leveling layer used in stone paving installations is compared to...A 1:3 cement mortar, the sand layer for the leveling of permeable bricks should contain no more than 5% cement to prevent the sand from becoming fluid. For large parking lots, parks, and squares, as well as for extensive areas paved with permeable bricks, an organized sub-base structure should be designed to fully utilize rainwater.

Sidewalks and pedestrian streets should choose permeable coefficients.Top-grade permeable bricks with compressive strength exceeding 40MPa and a thickness of over 60mm. For residential roadways (sidewalks), squares, and parking lots, select B-grade permeable bricks with compressive strength above 45MPa and a thickness of at least 60mm, preferably 80mm or 120mm. This ensures a balance between permeability and brick strength.

2. Permeable Paver Maintenance

Porous bricks excel in their permeability, reducing surface runoff and peak flood flows by enhancing rainfall infiltration, thereby lowering the risk of rainwater flooding and regulating local microclimates. However, porous bricks currently face issues such as blockages and durability, with blockages being particularly common. These can significantly degrade the bricks' permeability, shorten their lifespan, and impact rainwater infiltration and sponge city construction. Repeatedly replacing porous bricks not only wastes human, material, and financial resources but also hinders the realization and maintenance of urban functions. Appropriate measures to mitigate blockages and regular maintenance can restore the bricks' permeability, reduce engineering costs, and promote sustainable urban development.PC stone-like permeable pavers require the same daily maintenance as regular pavement bricks, including timely cleaning and care. To extend the permeability of the pavers, it is recommended to冲洗 the surface of the permeable pavers with a high-pressure water jet every six months, to remove any clogged dust within the microscopic pores of the pavers, thereby extending their permeability. With advancements in technology, a surfactant can now be sprayed on the surface of permeable pavers, enhancing and prolonging their effectiveness. This treatment should be performed annually.

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Status and Development Suggestions for Waterproofing Materials Laying in Shaoxing Market

1. The current status of permeable paver installations in the Shaoxing market
Currently, in the Shaoxing market, permeable bricks are predominantly made of standard permeable concrete bricks, with the adopted specifications being...The products primarily measure 200*100*60mm, utilizing recycled materials processed into crushed stone and stone powder. The permeable brick products have low strength and fail to meet the required permeability standards, resulting in poor visual appeal and comfort for pedestrians after installation. Furthermore, with no timely maintenance post-installation, the products did not meet the requirements for permeable paving after a period of use.

As the technology of permeable bricks continues to innovate, it has now developed to the fifth generation.——PC Stone-like Permeable Pavers. These pavers incorporate high polymer additives and a small amount of cement with natural quartz sand to enhance their surface wear resistance and aesthetic appeal. The surface texture of the pavers closely mimics that of stone and boasts superior permeability. The production of PC Stone-like Permeable Pavers utilizes imported German equipment, resulting in higher strength and larger sizes (up to 1000*1000*120mm), capable of meeting the permeable paving needs for large squares and various roadways. They can completely replace stone materials, making them a green, environmentally friendly new type of building material.
2. Recommendations for the Development of Permeable Paving
Effective policy guidance, leadership attention, and corresponding policy support are crucial means for promoting new building materials. For instance, the Ministry of Housing and Urban-Rural Development issued the "Development Plan for Building Energy Efficiency and Green Buildings during the 14th Five-Year Plan Period," which clearly states that by 2025, newly constructed urban buildings will be green buildings, with steady improvement in energy efficiency, gradual optimization of energy consumption structure, and effective control over the growth trend of energy consumption and carbon emissions, leading to the basic formation of a green, low-carbon, and circular construction and development pattern. Additionally, the Ministry of Industry and Information Technology released the "Directory of Technologies and Products Encouraged for Promotion in the Building Materials Industry (2023 Edition)" to promote the high-end, intelligent, and green transformation and upgrading of the building materials industry. Taking Hefei, Anhui Province as an example, PC imitation stone permeable bricks have completely replaced traditional stone paving, enhancing the city's level while aligning with the national industrial development direction.

Establish and improve the information pricing for various types of permeable paving. Only by establishing information pricing for different grades and types of permeable bricks can the products be enhanced. For instance, Hangzhou has established product information pricing for common concrete permeable bricks, artificial stone permeable bricks, and sand-based permeable bricks, allowing products of different grades to have distinct application scenarios and prices.

Expand the application of the new building material, permeable bricks, by selecting a group of capable new building materials and products manufacturers for key development and cooperation. This will enable them to develop distinctive characteristics, own leading products, a reasonable product structure, and possess a certain scale and complementary capabilities, forming a new materials base.

④ Technological advancements to promote the development of new building materials, based on the introduction, digestion, and absorption of advanced domestic and international technology equipment, are being researched and developed to suit China's national conditions. Strive to ensure that products are not only green and environmentally friendly but also conducive to sustainable innovation and development; enhance the development and establishment of products with strong functionality and social benefits.