微生物矿化修复混凝土裂缝抗渗水性能试验研究

微生物裂缝自修复混凝土能够有效地实现裂缝的自我诊断和自我修复。利用好氧嗜碱微生物Bacteria.H1的矿化沉积作用,将其作为自修复剂,且用膨胀珍珠岩固载Bacteria.H1,研制出了一种新型裂缝自修复混凝土。通过扫描电子显微镜(SEM)与X射线衍射(XRD)对裂缝填充物进行分析,养护28 d的修复结果证明该研究方法具有较好的自修复能力,试验中自修复混凝土修补最大裂缝宽度是0.72 mm,是普通混凝土最大自修复宽度的1.8倍,且裂缝沉淀物是以球形和棱柱体形式存在的碳酸钙晶体。通过抗渗水性能试验的研究,自修复混凝土试件养护7 d后,渗水系数比普通混凝土低72.28%,表明这种新型自修复混凝土具有良好的抗渗水性能。

Experimental study on water permeation resistance of concrete crack healed by microbial mineralization

Microbial mineralization repairs concrete cracks and can effectively achieve self-diagnosis and self-repair of cracks.In this study,a new type of crack self-repairing concrete was prepared by using light porous expanded perlite particles as the carrier of aerobic microorganism Bacteria.H1 self-repairing agent.The mineralization composition of the crack precipitation was subsequently analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD),and curing 28 d repair results prove that the research of this method has good self-healing ability,and the maximum value of completed healing crack width reached 0.72 mm,which is as 1.8 times as the value of ordinary concrete,and sediment and crack exist in the form of spherical and prism of calcium carbonate crystals.Through the water permeability performance test,after 7 days of self-repairing concrete specimens,the water permeability coefficient is 72.28%lower than that of ordinary concrete,indicating that this new self-repairing concrete has good water resistance.