Water retention

Exceptional water retention (thermal relaxation) for preventing heat island effect in urban areas

Porous concrete’s internal structure consists of 30% air, allowing it to drain and store rainwater.
With this high level of water retention, it can keep roads and buildings’ surface temperature from rising, preventing the heat island effect. Its water-retentive abilities can also prevent the sudden concentration of rainwater during torrential downpours and prevent downstream flooding.
The heat island effect causes temperature rise during summer in urban areas more than in surrounding regional areas. It has become a serious environmental issue caused by urbanization. The heat island effect is caused by heat radiated from the concrete walls of buildings and apartment blocks, and the heat radiated off of asphalt ground. It’s also thought to be a factor in causing torrential and heavy rainfall. Porous concrete, which is highly water retentive, proves effective against the heat island effect that can cause enough rainfall to exceed the drainage abilities of cities’ sewer systems largely.

The thermal relaxation properties in multi-layered porous concrete

Porous concrete’s function in preventing temperature rises

As well as being internally ventilated, porous concrete can also retain water, allowing it to effectively avoid temperature rises that occur due to solar radiation during summer. This helps to prevent the heat island effects in urban areas.

Results from Measuring Outdoor Surface Temperatures

Porous concrete has a little temperature rise, and it has been proven to rapidly lower in temperature after sunset. This experiment shows that the air gaps and high water retention levels in porous concrete are effective against lessening the heat island effect.

Comparison of Surface Temperatures

The measuring of surface, internal and base temperature changes across 24 hours

Concrete Type	Temperatures
	MAX	at 8 pm
Porous concrete	34℃	26℃
Conventional concrete	38℃	29℃
Asphalt	51℃	30℃