Response surfaces for compressive strength of concrete

The aim of total quality management (TQM) is to offer satisfactorily high quality products to customers for providing increased productivity and decreased costs. Various methods are used for process improvement, development and optimization. In ready mixed concrete production, the number and the variations of effect parameters can be reduced using response surface methodology.In this study, firstly influence levels of the main and interaction terms of effect variables were determined using 27–3 fractional factorial design in order to reduce the number of simultaneously controllable variables. Then, quadratic terms were determined using D-Optimal design, and response surface graphics were plotted.

► Desirabilities of responses govern the choice of effect variables in mix design. ► Desirabilities of variables should be taken into consideration in optimization. ► Separate evaluations of categoric effect variables increases the power of model. ► The range of each effect variable is of crucial importance in elimination process. ► Significance of a model term must be assessed based on the attribute it represents.