Compressive strength values dispersion of concrete mixtures designed in central and in situ
AbstractThe compressive strength test method has been the most used test to evaluate the quality of concrete in the hardened state due to the simplicity in the execution, the reliability of the results achieved and the low cost. Regardless of whether concrete to be produced in concrete central or at the construction site (in situ), the requirement for the application of compressive strength test is a constant, because it allows the prediction of resistence capacity of the structure piece. However it must ensure that there is a correlation between the strength values obtained for concrete produced in central and in situ that can intervene in the correct analysis of quality. For this, the purpose was to make a dispersion relation of seven concrete with compressive strengths of 20, 25, 30, 35 and 40 MPa. Two mixtures (35 MPa and 40 MPa) were performed in central, while five concrete mixtures were performed in situ, by five different worker's group with same time of experience on concrete’s manufacture.