Scholarlink

<p>Microbially induced calcium carbonate precipitation is limited by the surface carbonate accumulation during concrete crack repair, and its long-term sealing performance requires improvement. The present study aimed to enhance the repair depth, bond strength, and volume stability by using a combined culture of urea-hydrolytic and carbon-fixing bacteria. The optimum volume ratio of the mixed bacterial solutions was determined to be 6:4 between the urea-hydrolyzing bacteria (<i>Sporosarcina pasteurii</i> ATCC 11859) and carbon-fixing bacteria (<i>Bacillus subtilis</i> CMCC 63501), based on the maximum precipitation rate and first-order rate coefficient. The repair quality of the mixed bacterial solution was enhanced with a permeability coefficient reduced by 99.6%. Moreover, the median deposition depth increased from 1.75&#xa0;cm in the urea hydrolytic bacteria group to 2.8&#xa0;cm in the mixed bacteria group. Meanwhile, the precipitation induced by the mixed bacteria showed an improved bond strength, attributed to a shift in crystal form from vaterite-dominated to calcite-dominated. The sustained carbonate ion supply by carbon fixing bacteria promoted the vaterite-to-calcite transformation, yielding denser precipitation and superior volume stability under wet–dry cycling.</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

Synergistic bio-calcification: dual bacterial strains for deep crack repair and permeability reduction in concrete

  • 期刊论文

  • 发表日期：

    2026年5月5日

查看全文
  • Qi Fan,
  • Liang Fan,
  • Wai-Meng Quach,
  • Jizhou Duan

摘要

Microbially induced calcium carbonate precipitation is limited by the surface carbonate accumulation during concrete crack repair, and its long-term sealing performance requires improvement. The present study aimed to enhance the repair depth, bond strength, and volume stability by using a combined culture of urea-hydrolytic and carbon-fixing bacteria. The optimum volume ratio of the mixed bacterial solutions was determined to be 6:4 between the urea-hydrolyzing bacteria (Sporosarcina pasteurii ATCC 11859) and carbon-fixing bacteria (Bacillus subtilis CMCC 63501), based on the maximum precipitation rate and first-order rate coefficient. The repair quality of the mixed bacterial solution was enhanced with a permeability coefficient reduced by 99.6%. Moreover, the median deposition depth increased from 1.75 cm in the urea hydrolytic bacteria group to 2.8 cm in the mixed bacteria group. Meanwhile, the precipitation induced by the mixed bacteria showed an improved bond strength, attributed to a shift in crystal form from vaterite-dominated to calcite-dominated. The sustained carbonate ion supply by carbon fixing bacteria promoted the vaterite-to-calcite transformation, yielding denser precipitation and superior volume stability under wet–dry cycling.