Preparation and properties of ultra-high performance concrete incorporation multi-mineral admixtures

The impact of multi-mineral admixtures on the sturdiness of ultra-high performance concrete (UHPC). In this study on the premise that multi-mineral admixtures can be utilized in UHPC, we optimized the percentage of three admixtures(limestone powder,slag, and pumice powder) that can replace cement using the Box-Behken design response surface method, and prepared UHPC specimens with multi-mineral admixtures. The rationality of the multi-mineral admixtures approach proposed in this study was confirmed by characterizing the mechanical properties and porosity of the prepared specimens. Durability was also investigated through relevant tests. The results showed that the porosity of the prepared UHPC decreased by 49.4%, the mechanical properties improved by 14.7%, the self-shrinkage and drying shrinkage decreased by 9.8% and 6.2%, respectively, and the volume stability improved. Moreover the resistance to sulfate dry-wet cycling, chloride ion permeation, and carbonization improved significantly. This study, thus, demonstrates a new type of multi-mineral admixture for UHPC with excellent mechanical properties and durability.