Summer is approaching. What precautions need to be taken this time of year when planning to place concrete?
Hot weather must be taken into account when planning concrete projects because of the potential effects on fresh and recently placed concrete. High temperatures alone cause increased water demand which, in turn, results in lower concrete strength. Higher temperatures can also cause loss of entrained air in concrete, which could affect long-term durability. High temperatures, high wind velocity and low relative humidity can affect fresh concrete in two ways. One, the high rate of evaporation may cause early plastic shrinkage shrinkage. Two, the evaporation rate can remove surface water necessary for hydration unless proper curing methods are employed. If you decide to tackle your project in the heat of the summer, make sure you have adequate manpower to quickly place, finish and cure the concrete. Limit the addition of water at the jobsite. Excess water is always detrimental to concrete. Talk to your ready-mix supplier about fly ash and/or retarder. Both products slow the heat of hydrat
