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This research paper delves into self-compacting concrete (SCC), a type of concrete that consolidates without the need for vibration. However, external loading and chemical reactions often lead to the development of microcracks. Addressing this issue, the study concentrates on CaCO3 precipitation in SCC as a method for self-healing microcrack repair. The research encompasses five different concrete mixes, incorporating two supplementary cementitious materials (SCMs), microsilica (MS), and metakaolin (MK), with and without the inclusion of the bacteria Sporosarcina pasteurii. Experimental findings indicate that mixes SCCMSSP and SCCMKSP increased compressive strength by 15.32% and 21.29%, tensile strength by 12.1% and 16.14%, and flexural strengths by 15.62% and 21.88%, respectively, at 28 days compared to the corresponding control mix. Moreover, these mixes improved compressive strength by 10.86% and 20.28%, tensile strength by 15.34% and 20.82%, and flexural strength by 17.65% and 26.47%, respectively, at 56 days compared to the corresponding control mix. The concrete's integrity concerning self-healing ratio, damage level, and strength regain ratio was evaluated through an ultrasonic pulse velocity test. Results showed that mix SCCMKSP exhibited optimal reduction of damage level by 27.36%, and mixes SCCMSSP and SCCMKSP demonstrated healing efficiencies of 14.06% and 12.52% at 28 days and 14.84% and 15.64% at 56 days, respectively, compared to the corresponding control mix. The research also employed scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to examine the mobility and elemental composition of bacterial concrete. These analyses further bolster the positive effects of bacteria in enhancing the self-healing capabilities of SCC mixes when combined with mineral admixture.

来源平台：INNOVATIVE INFRASTRUCTURE SOLUTIONS