Field and Laboratory Study of Modulus of Rupture and Permeability of Structural Concretes in Florida

摘要

An extensive laboratory study was conducted to evaluate the effects of various mix parameters and curing conditions on these two properties of structural concretes used in Florida, and the relationship of other concrete strength properties, to these two properties. An efficient laboratory test set-up for performing forty permeability tests simultaneously was developed and used in the study. In addition, concrete samples obtained from six concrete projects in Florida were tested to evaluate the differences between the in-service concrete and the laboratory-cured concrete. The scope of the laboratory study covered three aggregate types (a Florida porous limestone, a river gravel, and an Alabama dense limestone), three cement types (Types I, II and III), three water/cement-ratios (0.45, 0.38 and 0.33), three maximum aggregate sizes (3/8, 3/4 and 1 inch), two pozzolans (fly ash and silica fume) and six curing conditions (steam curing, air curing, curing compound and three moist curing conditions). The results of the study indicated that water/cement-ratio and curing condition are the major factors affecting the properties of concrete.