WHY Do Concrete Surfaces Craze?
Concrete surface crazing usually occurs because one or more the rules of “good concrete practice” were not followed. The most frequent violations are: a. Poor or inadequate curing. Intermittent wet curing and drying or even the delayed application of curing will permit rapid drying of the surface and provoke crazing. b. Too wet a mix, excessive floating, the use of a jitterbug or any other procedures, which will depress the coarse aggregate and produce an excessive concentration of cement paste and fines at the surface. c. Finishing while there is bleed water on the surface or the use of steel trowel at a time when the smooth surface of the trowel brings up too much water and cement fines. Use of a bull float or darby while bleed water is on the surface will produce a high water-cement ratio weak surface layer which will be susceptible to crazing, dusting and other defects. d. Sprinkling cement on the surface to dry up the bleed water is a frequent cause of crazing surfaces. This conce