剑麻纤维负载微生物在混凝土裂缝自愈合中的应用  

Application of Sisal Fiber with a Microbial Load in Concrete Cracks Self-healing

作　　者：彭海鑫 王华松 郭远臣[1] Peng Haixin;Wang Huasong;Guo Yuanchen

机构地区：[1]重庆三峡学院土木工程学院,重庆404100

出　　处：《重庆建筑》2023年第3期37-41,共5页Chongqing Architecture

基　　金：重庆市教育科学技术研究计划(JZD-2021101201)。

摘　　要：利用微生物诱导碳酸盐沉淀以实现混凝土微裂缝的自愈合成为近年来的研究热点,研究发现,适宜的载体对自愈合的效果有着决定性的作用。该文选用剑麻纤维作为载体,制备一种带有微生物生物膜的剑麻纤维混凝土裂缝自愈合混凝土,在研究负载微生物后芽孢在高碱性环境中活性以及优化剑麻纤维掺量的基础上,评价其自愈合能力与材料的力学性能。结果表明:负载在剑麻纤维中的芽孢,经高碱溶液长时间处理后,脲酶活性仍达到95.9%;剑麻纤维掺量为胶凝材料质量的0.7%时为最优掺量;采用剑麻纤维作为微生物负载材料的混凝土修复效果和力学性能均优于对照组,其中,劈裂抗拉强度和抗压强度较普通混凝土分别提高15.3%、25.1%,抗渗修复率达到94.7%,初始裂缝宽度0.9 mm以内的裂缝,其愈合率达到100%,最大修复宽度为1.12 mm。The use of microorganisms to induce carbonate precipitation to achieve the self-healing of concrete micro-cracks has become a research hotspot in recent years.Studies have found that suitable carriers play a decisive role in the self-healing process.Taking sisal fiber as a carrier,this paper made a crack self-healing concrete with a microbial biofilm from sisal fiber and,based on a study of the activity of postspore,a loaded microorganism,in the high alkaline environment and the optimization of the sisal fiber content,evaluates its self-healing ability and the mechanical properties of the material.The results indicate that the spore loaded in sisal fiber has the urease activity of 95.9%after long immersion in high alkalinity;The optimum mixing amount of sisal fiber is 0.7%of the weight of cementing materials.The concrete using sisal fiber as the microorganism loading material shows better mechanical properties and self-healing performance than the control group.Specifically,the splitting tensile strength and compressive strength of the concrete compared with common concrete has increased by 15.3%and 25.1%,respectively,the anti-seepage repairing rate has reached 94.7%,and the healing rate of cracks with the initial width of within 0.9 mm has reached 100%,and the maximum repair width is 1.12 mm.

关 键 词：微生物 自愈合 剑麻纤维 力学性能 裂缝 混凝土 

分 类 号：TU502[建筑科学—建筑技术科学]