Scholarlink

<p>Cracking in concrete leads to the ingress of harmful agents such as moisture, rain, and salts which compromises the durability of concrete. Traditional repair methods prove to be time-consuming, costly, and inadequate, especially in the case of complex structures. Economic statistics show increasing costs related to the repair and maintenance of concrete infrastructures. To overcome these challenges, the development of self-healing concrete is the only possible means by which to detect and repair cracks without human intervention. The healing of cracks in concrete by bacterial microorganisms occurs through microbial-induced calcium carbonate precipitation (MICCP). This review systematically explores the influence of an interplay of factors on MICCP such as bacterial type, the concentration of bacteria, availability of nutrients, encapsulation techniques of bacterial spores, ambient temperature, pH of the cementitious-based system and the curing regimes used in different literature studies. Applications of MICCP in engineering practices, the restoration of mechanical characteristics, and the enhancement of durability properties of bacteria-based self-healing concrete (BBSHC) are critically analyzed. Furthermore, the effectiveness of self-healing and self-healing efficiency for different crack widths of BBSHC is examined. Finally, microstructural characteristics of the bacterial precipitate formed within the healed cracks are studied highlighting characterization techniques, including XRD, SEM and FTIR analyses. Based on the conclusions of this review some future recommendations are also provided. This comprehensive review offers insights into optimizing the MICCP for improving the durability performance of BBSHC. Based on this comprehensive review, it was found that bacterial type, nutrient media, curing conditions, and encapsulation techniques significantly influence self-healing performance. Alkali-resistant bacteria like Bacillus strains and ureolytic bacteria proved effective in harsh cementitious environments, while encapsulation techniques using lightweight aggregates and porous materials enhanced bacterial survivability and crack closure efficiency. BBSHC achieved healing of cracks up to 1&#xa0;mm under optimal conditions, surpassing the 0.3&#xa0;mm limit of autogenous healing. Microstructural evaluations using advanced techniques confirmed the production of calcite as the primary healing product. These findings provide valuable insights into optimizing MICCP for improved durability and crack-healing performance in concrete systems.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Factors influencing bacterial-based precipitation, assessment of crack inducing, durability and characterization methods: a comprehensive review

  • 期刊论文

  • 发表日期：

    2025年2月18日

查看全文
  • Izhar Ahmad,
  • Mehdi Shokouhian,
  • Marshell Jenkins,
  • Gabrielle L. McLemore

摘要

Cracking in concrete leads to the ingress of harmful agents such as moisture, rain, and salts which compromises the durability of concrete. Traditional repair methods prove to be time-consuming, costly, and inadequate, especially in the case of complex structures. Economic statistics show increasing costs related to the repair and maintenance of concrete infrastructures. To overcome these challenges, the development of self-healing concrete is the only possible means by which to detect and repair cracks without human intervention. The healing of cracks in concrete by bacterial microorganisms occurs through microbial-induced calcium carbonate precipitation (MICCP). This review systematically explores the influence of an interplay of factors on MICCP such as bacterial type, the concentration of bacteria, availability of nutrients, encapsulation techniques of bacterial spores, ambient temperature, pH of the cementitious-based system and the curing regimes used in different literature studies. Applications of MICCP in engineering practices, the restoration of mechanical characteristics, and the enhancement of durability properties of bacteria-based self-healing concrete (BBSHC) are critically analyzed. Furthermore, the effectiveness of self-healing and self-healing efficiency for different crack widths of BBSHC is examined. Finally, microstructural characteristics of the bacterial precipitate formed within the healed cracks are studied highlighting characterization techniques, including XRD, SEM and FTIR analyses. Based on the conclusions of this review some future recommendations are also provided. This comprehensive review offers insights into optimizing the MICCP for improving the durability performance of BBSHC. Based on this comprehensive review, it was found that bacterial type, nutrient media, curing conditions, and encapsulation techniques significantly influence self-healing performance. Alkali-resistant bacteria like Bacillus strains and ureolytic bacteria proved effective in harsh cementitious environments, while encapsulation techniques using lightweight aggregates and porous materials enhanced bacterial survivability and crack closure efficiency. BBSHC achieved healing of cracks up to 1 mm under optimal conditions, surpassing the 0.3 mm limit of autogenous healing. Microstructural evaluations using advanced techniques confirmed the production of calcite as the primary healing product. These findings provide valuable insights into optimizing MICCP for improved durability and crack-healing performance in concrete systems.