The hardening of concrete is highly dependent on the environmental conditions that it is in. Countries like Australia, where climates are primarily hot, the rate by which concrete hardens is faster.

1. Hot Environments Lessen
the Compressive Strength
of Concrete
Timberfix

2. The hardening of concrete is highly dependent on the environmental conditions that it is in.
Countries like Australia, where climates are primarily hot, the rate by which concrete hardens is
faster.
This becomes an issue for contractors and builders alike, who need to dry the concrete over a
specific period during construction. As such, noting the hot weather patterns helps determine which
steps to take to offset the quick concrete hardening rate.
Australia’s Climate Is Unideal to Setting Concrete
Hot climates, such as the ones found in Australia’s desert north, make for unfavourable building
conditions. This is because the high temperature hastens the setting time of concrete, which needs
to set over a recommended amount of time to achieve full durability.
As stated by ConcreteNetwork.com, concrete set as cement hydrates, a process that generates heat.
As cement hydrates, it absorbs water and grows crystals near aggregate particles that determine
compressive strength.

3. Because of the hot weather heating up the concrete, the hydration process speeds up and reduces
the time the crystals between the concrete and cement has to develop. This leads to concrete with
less compressive strength. In fact, the compressive strength of concrete poured and set in hot
conditions normally have 10 percent less compressive strength than that of normal concrete.
Lower compressive strength simply means that the wall or foundation is more likely to break under
pressure, so finding a way to ensure that the concrete does not set faster is a priority.
Offsetting Quick Concrete Setting with Retarders
Concrete retarders work by delaying the setting time of concrete no matter the weather condition,
so this product is perfect for Australia’s hot regions. Moreover, these products are useful because
they help maintain the concrete’s workability.
Australia’s many varying weather patterns, especially its hot climates, can all have adverse effects
on building projects. It is important, then, for builders and contractors to invest in concrete
retarders as these products are the best way to avert early concrete setting.

4. References:
http://www.cement.org/cement-concrete-applications/concrete-materials/chemical-admixtures
http://www.timberfix.com.au/category/289-sika
https://www.corrosionpedia.com/definition/1620/compressive-strength-material-science
https://www.concretenetwork.com/hot-weather-concreting/problem.html