微生物作用下混凝土裂缝修复效果试验研究

Experimental study on repair of concrete cracks by microbial action

微生物矿化作用可以有效愈合混凝土裂缝,达到修复混凝土裂缝的目的.本文以带裂缝混凝土为研究对象,设置0.2、0.3、0.6 mm三个裂缝宽度和20、30 mm两个裂缝深度,以巴氏芽孢杆菌为菌株,通过裂缝观测、超声波测试、立方体抗压强度测试及裂缝内部微生物沉积物质的微观形貌分析,研究微生物对不同深度及宽度混凝土裂缝的修复效果.研究结果表明:巴氏芽孢杆菌可有效修复混凝土表面裂缝;氧气的供给是微生物在裂缝内部矿化的重要环境条件,随着裂缝深度的增加,巴氏芽孢杆菌的修复效果减弱;随着裂缝宽度的增大,微生物在裂缝内部的矿化效果减弱.

Microbial mineralization can effectively heal concrete cracks and therefore achieving the purpose of repairing concrete structures.In this paper,concrete specimens with cracks were taken as the research object.Bacillus pasteurii was used as the healing agent to repair the concrete specimens under different crack conditions,i.e.with width of 0.2 mm,0.3 mm and 0.6 mm and depth of 20 mm and 30 mm,respectively.Through crack observation,ultrasonic testing,compressive strength testing and microscopic morphology analysis,the repair effects of the selected microorganism on concrete cracks were evaluated.The results show that Bacillus pasteurii can repair the surface cracks of concrete effectively.The supply of oxygen provides the necessary environmental condition for the mineralization of microorganisms inside the cracks.As the depth of the crack increases,the repair effect of Bacillus pasteurii decreases,and as the width increases,the mineralization effect of microorganisms in the cracks is weakened.