TY - JOUR
T1 - The method of repairing microcracks based on microbiologically induced calcium carbonate precipitation
AU - Sun, Xiaohao
AU - Miao, Linchang
AU - Wu, Linyu
AU - Wang, Chengcheng
AU - Chen, Runfa
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (no. 51578147), the Scientific Research Foundation of the Graduate School of Southeast University (no. YBJJ1846) and the Postgraduate Research and Practice Innovation Program of Jiangsu Province (no. KYCX18_0107).
Publisher Copyright:
© 2020 ICE Publishing. All rights reserved.
PY - 2020/6/1
Y1 - 2020/6/1
N2 - Cracks will affect the service life of concrete, even if they are small ones. A crack healing method based on biomineralisation is presented to repair microcracks in concrete specimens. By analysing the change in permeability, adopting two different ultrasonic detection methods, and conducting unconfined compressive strength tests, scanning electron microscopy and X-ray diffraction tests, this method of repair was proved to be effective and its repair effect was evaluated. Results show that the permeability of specimens repaired using this healing method declines significantly, but samples with a crack width of 0·05 mm experience a different decreasing trend from those with crack width of 0·15 mm. The unrepaired crack depths of samples with a crack width of 0·15 mm are almost zero, and the smaller the crack widths, the larger the unrepaired crack depths. Using this healing method, samples with wider cracks (0·10 mm and 0·15 mm) are repaired more effectively and regained higher strengths. As a consequence, the healing method can repair small cracks between 0·05 mm and 0·15 mm in concrete, but wider cracks (0·10 mm and 0·15 mm) are repaired more completely and show improved effectiveness of the repair. The healing method and results of repair provide an important reference for subsequent study on the practical repair of microcracks.
AB - Cracks will affect the service life of concrete, even if they are small ones. A crack healing method based on biomineralisation is presented to repair microcracks in concrete specimens. By analysing the change in permeability, adopting two different ultrasonic detection methods, and conducting unconfined compressive strength tests, scanning electron microscopy and X-ray diffraction tests, this method of repair was proved to be effective and its repair effect was evaluated. Results show that the permeability of specimens repaired using this healing method declines significantly, but samples with a crack width of 0·05 mm experience a different decreasing trend from those with crack width of 0·15 mm. The unrepaired crack depths of samples with a crack width of 0·15 mm are almost zero, and the smaller the crack widths, the larger the unrepaired crack depths. Using this healing method, samples with wider cracks (0·10 mm and 0·15 mm) are repaired more effectively and regained higher strengths. As a consequence, the healing method can repair small cracks between 0·05 mm and 0·15 mm in concrete, but wider cracks (0·10 mm and 0·15 mm) are repaired more completely and show improved effectiveness of the repair. The healing method and results of repair provide an important reference for subsequent study on the practical repair of microcracks.
KW - Compressive strength
KW - Permeability
UR - http://www.scopus.com/inward/record.url?scp=85080059224&partnerID=8YFLogxK
U2 - 10.1680/jadcr.18.00121
DO - 10.1680/jadcr.18.00121
M3 - Journal article
AN - SCOPUS:85080059224
SN - 0951-7197
VL - 32
SP - 262
EP - 272
JO - Advances in Cement Research
JF - Advances in Cement Research
IS - 6
ER -