Tests and methods of evaluating the self-healing efficiency of concrete: A review
| Autor: | Nasiru Zakari Muhammad, Mostafa Rezazadeh Shirdar, Sib Krishna Ghoshal, Abideen Adekunle Ganiyu, Mostafa Samadi Kouchaksaraei, Hesam Kamyab, Seyed Esmaeil Mohammadyan Yasouj, Ali Keyvanfar, Arezou Shafaghat, Mohammad Mahdi Taheri, Ronald McCaffer, Muhd Zaimi Abd Majid |
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| Rok vydání: | 2016 |
| Předmět: |
Cement
Materials science business.industry 0211 other engineering and technologies 02 engineering and technology Building and Construction Structural engineering 021001 nanoscience & nanotechnology Microstructure Durability Experimental strategy 021105 building & construction Service life General Materials Science Macro 0210 nano-technology business Calcium carbonate precipitation Reliability (statistics) Civil and Structural Engineering |
| Zdroj: | Construction and Building Materials. 112:1123-1132 |
| ISSN: | 0950-0618 |
| DOI: | 10.1016/j.conbuildmat.2016.03.017 |
| Popis: | To achieve the extended service life of the concrete material, expansive chemicals and microbial induced calcium carbonate precipitation are used, which induced autonomous healing of cracks in concrete. Various approaches are adopted to develop self-healing cement based materials, where experiments are conducted to establish a new method of self-healing. However, comprehensive evaluations of self-healing efficiency are not performed at the level of macro-, micro- and nano scale. Existing approaches evaluated the self-healing efficiency at the macrostructure level. These are based on the durability criterion of water absorption, chloride and acid resistance. Tests at microstructure level are commonly performed to maximize the reliability of the results. Only few tests are conducted at the nanostructure level. It is worth to review all the available tests and methods on self-healing efficiency assessment of cement based materials to develop innovative experimental strategy. Use of supplementary cementing materials, polymers and microorganisms are the most familiar approaches to achieve effective self-healing. Determining the effect of self-healing to successfully sealing the crack width is the key issue. So far, a crack of maximum size of 0.97 mm is healed. Visual observation based on microscope, digital imaging and camera photographs are the primary techniques to assess the width of the filled cracks. Yet, only couple of researches reported on the healing of crack depths of 32 mm and 27.2 mm. Besides, only one report acknowledged the healing of crack length of 5 mm. |
| Databáze: | OpenAIRE |
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