To slow down the setting of concrete, which ingredient would typically be added?

To slow down the setting of concrete, a retarding admixture is typically added. This type of chemical additive helps to delay the chemical hydration process of the cement, which in turn prolongs the time before the concrete sets or hardens. This can be particularly beneficial in hot weather conditions, where rapid setting could compromise the workability of the concrete and make it challenging to achieve proper finishing.

Retarding admixtures are often used in situations where the concrete needs to be transported over long distances or when it is necessary to delay the setting time for various operational reasons, such as allowing for extended work time with the mix. This ensures that the quality of the finished concrete is maintained while accommodating practical workflow needs.