摘要
混凝土作为现代建筑的核心材料,其裂缝问题严重威胁结构的耐久性。传统修复方法存在效率低、成本高等局限,而微生物自修复技术通过诱导碳酸钙沉淀实现裂缝自主愈合,已成为新兴研究热点。本文系统综述了微生物诱导碳酸钙沉淀(MICCP)的作用机制,重点探讨尿素水解、钙盐氧化、硝酸盐还原、光合作用驱动及异化硫酸盐还原等不同途径的MICCP过程。其中,尿素水解法修复效率高,但伴随有害副产物铵离子;钙盐氧化法规避氨污染,但沉淀速率较低;硝酸盐还原法适用于缺氧环境,但修复宽度受限;光合作用驱动法兼具碳封存功能,但依赖光照条件。分析表明,pH值、温度、湿度、氧含量及菌液浓度等环境参数显著影响尿素水解MICCP技术的修复效能,脲酶活性在pH值为8.5~11时最高,高温加速沉淀但极端条件抑制微生物存活。尽管MICCP技术已成功应用于水渠、隧道等工程,但仍面临微生物活性随龄期衰减、深层裂缝修复效率低、高碱环境抑制及规模化成本高等挑战。未来需通过筛选耐极端环境菌株、开发多菌种协同体系、优化载体封装技术及融合智能算法,推动自修复混凝土的工业化应用,助力可持续建筑发展。
As a core material in modern construction,concrete faces a significant threat to its structural durability from cracking.Traditional repair methods are limited by low efficiency and high costs.In contrast,microbially induced self-healing technology,which achieves autonomous crack healing by inducing calcium carbonate precipitation,has emerged as a new research focus.This paper systematically reviews the mechanisms of microbially induced calcium carbonate precipitation(MICCP),with a focus on exploring different MICCP pathways,including urea hydrolysis,calcium salt oxidation,nitrate reduction,photosynthesis-driven,and dissimilatory sulfate reduction.Among these,the urea hydrolysis method offers high repair efficiency but is accompanied by the harmful by-product ammonium ions;the calcium salt oxidation method avoids ammonia pollution but has a lower precipitation rate;the nitrate reduction method is suitable for anoxic environments but is limited in repair width;and the photosynthesis-driven method combines carbon sequestration functionality but relies on light conditions.Analysis indicates that environmental parameters such as pH,temperature,humidity,oxygen content,and bacterial concentration significantly influence the repair efficacy of urea hydrolysis-based MICCP.Urease activity is highest at pH values between 8.5 and 11.Elevated temperatures accelerate precipitation,but extreme conditions inhibit microbial survival.Although MICCP technology has been successfully applied in engineering projects such as water channels and tunnels,it still faces challenges including the attenuation of microbial activity over time,low repair efficiency for deep cracks,inhibition in highly alkaline environments,and high costs for large-scale application.Future efforts should focus on screening microbial strains resistant to extreme environments,developing multi-strain synergistic systems,optimizing carrier encapsulation technologies,and integrating intelligent algorithms to promote the industrial application of self-healing concrete and support sustainable construction development.
出处
《混凝土世界》
2025年第12期80-87,共8页
China Concrete
关键词
混凝土裂缝
微生物
自修复
生物矿化
碳酸钙沉淀
Concrete cracks
microorganisms
self-healing
biomineralization
calcium carbonate precipitation
