One of the fundamental materials that has created the modern world, reinforced concrete is the backbone that allows for gigantic manufacturing plants, huge bridges spanning mile after mile and roads that can last for decades with minimal repair and maintenance.
However, one question that has been raised about concrete, much like any other material, is how well it survives an intense heatwave or a particularly prolonged period of weather that is hotter than the norm.
Concrete is vulnerable to thermal cracking, which is when temperature changes within the concrete structure create internal stresses.
This is most commonly found soon after concrete is laid, as the expansion process needs to occur at a uniform rate to avoid the uneven stresses and pressures from pushing against each other, creating cracks and other forms of concrete damage.
However, it is also possible at particularly high temperatures for concrete to lose durability even after cracking and remaining in situ for a considerable amount of time.
Whilst most concrete damage occurs at closer to 90 degrees Celsius, material fatigue and weakness can begin at the same temperatures experienced during the May and June 2026 heatwaves.
Concrete can lose moisture at around 38 degrees Celsius, which can affect its strength and durability, and fatigue cracks can occur if there are sudden shifts in temperature.
This is why the commonly seen trick of splashing a patio with water can cause it to crack rather suddenly. Less intentionally, a heatwave followed by an immediate thunderstorm can potentially cause the same problem if the temperature does not change gradually.
However, using the right reinforcement can help as the fibres and rebar hold the concrete together and provide extra flex that concrete traditionally does not have.
Which Weather Factors Affect The Lifespan Of Concrete?
- High ambient temperatures often mean the concrete is significantly hotter than the air.
- Low humidity, as dry air dries out concrete.
- Exposure to hot winds can also suddenly dry out concrete.
