Surface Evaporation


Listed below is a graph from ACI 305 R which calculates the rate of evaporation. The primary cause of shrinkage cracks in concrete is when the rate of evaporation approaches 0.20 lb./sq.ft./hr or higher. Wind velocity, relative humidity, air temperature, and concrete temperature can be plotted on this graph to predict when plastic shrinkage cracking will occur and when EVRT should be employed.