Evaluation of plastic shrinkage cracking of self-compacting concrete
This paper describes an experimental investigation of plastic shrinkage cracking of self-consolidating concrete (SCC). Five SCC mixtures with compressive strengths ranging from 30 to 50 MPa were compared to five ordinary concrete (OC) mixtures. Free and restrained plastic shrinkage tests were performed in drying conditions. Depending on evaporation rate, plastic shrinkage occurs before setting (wind), or before and during setting (no-wind). In the presence of wind, SCC and OC mixtures have almost the same plastic shrinkage. Moreover, restrained shrinkage tests reveal that cracks of SCC tend to be less wide than cracks of OC. Nevertheless, when evaporation rate is low, SCC mixtures exhibit a higher plastic shrinkage than OC mixtures, due to their lack of bleeding. Consequently, SCC could be more vulnerable to shrinkage cracking, especially during setting. Thus, curing is recommended to protect SCC against evaporation at the fresh state.