Cold weather concrete: innovative mixtures designs and protection methods
| dc.contributor.author | Soliman, Ahmed Mohammed Yasien | |
| dc.contributor.examiningcommittee | El-Salakawy, Ehab (Civil Engineering) Kordi, Behzad (Electrical and Computer Engineering) Wang, Kejin (Institute for Transportation, Iowa State University) | en_US |
| dc.contributor.supervisor | Bassuoni, Mohamed (Civil Engineering) | en_US |
| dc.date.accessioned | 2020-10-23T16:43:19Z | |
| dc.date.available | 2020-10-23T16:43:19Z | |
| dc.date.copyright | 2020-10-15 | |
| dc.date.issued | 2020-07-30 | en_US |
| dc.date.submitted | 2020-10-15T22:17:03Z | en_US |
| dc.degree.discipline | Civil Engineering | en_US |
| dc.degree.level | Doctor of Philosophy (Ph.D.) | en_US |
| dc.description.abstract | In cold regions, concrete practitioners face challenges to achieve target performance criteria of concrete produced under low temperatures. There is still dearth of knowledge on how to alleviate the heating requirements for cold weather concreting. Nano-silica has the potential to produce concrete mixtures with dense microstructure and improved hardened properties under cold temperatures. This thesis applied the response surface method to assess the effect of multiple parameters on 40 concrete mixtures cast and cured under freezing temperatures down to -5℃. In addition, a comprehensive study was conducted to further understand the behavior of these mixtures and suitability for repair applications under cold temperatures. Also, this thesis explored the efficacy of using a hybrid protection system (insulation blankets + Phase change material (PCM) mat) on hydration development, mechanical properties and bonding behavior with steel of nano-modified concrete cured under lower freezing temperatures (-10 and -20℃), without heating, using experimental and numerical studies. The results suggested that the incorporation of at least 2% nano-silica with single or blended binders (maximum of 15% fly ash), especially with low w/b and calcium nitrate-nitrite (CNAI), achieved satisfactory performance when cured under freezing temperatures down to -5℃. This was substantiated by the complementary investigation which proved the applicability of nano-modified concrete, especially with a higher nano-silica dosage (4%) without and with fly ash (15%), for repair applications. Hence, it achieved satisfactory performance and compatibility with parent concrete. Furthermore, the experimental and numerical results showed that nano-modified concrete comprising CNAI, without or with fly ash (20%) and protected using the hybrid system achieved adequate hydration development, mechanical properties and bonding with steel re-bars due to the nucleation, pozzolanic and filler effects of nano-silica. Moreover, the developed thermal analysis and mechanical models showed an adequate generalization capability to predict concrete-steel interfacial temperature evolution, as well as bond strength with less than 10% error between predicted and experimental results. The synoptic outcomes of this thesis suggest that nano-modified concrete mixtures and hybrid protection system may provide an integrated strategy for alleviating heating requirements and improving the quality of concrete for various cold weather concreting applications down to -20℃. | en_US |
| dc.description.note | February 2021 | en_US |
| dc.identifier.citation | Yasien, A., Bassuoni, M. T., Abayou, A. and Ghazy, A. “Nano-modified Concrete as a Repair Material in Cold Weather” ACI Materials Journal. (Accepted in Sep. 2020, In-Press) | en_US |
| dc.identifier.citation | Yasien, A., Bassuoni, M. T. and Ghazy, A. “Concrete Incorporating Nano-Silica Cured under Freezing Temperatures Using Conventional and Hybrid Protection Methods” ASCE Journal of Materials in Civil Engineering. (Accepted in Sep. 2020). | en_US |
| dc.identifier.citation | Yasien, A. and Bassuoni, M. T. “Bonding of Nano-Modified Concrete with Steel under Freezing Temperatures using Different Protection Methods” Computers and Concrete, Vol. 26, No. 3, 2020, pp. 257-273. | en_US |
| dc.identifier.citation | Yasien, A. and Bassuoni, M. T. “Nano-modified concrete at sub-zero temperatures: experimental and statistical modelling”, Magazine of Concrete Research. (Accepted in Sep. 2019, Online first Nov. 2019, In-Press). | en_US |
| dc.identifier.citation | Yasien, A., Abayou, A. and Bassuoni, M. T. “Behavior of Nano-Modified Fly Ash Concrete Cast and Cured at Low Temperature” ACI Special Publication: Nanotechnology for Improved Concrete Performance, M. R. Taha and M. T. Bassuoni (Eds.), pp. 112-127, 2019. | en_US |
| dc.identifier.citation | Abayou, A., Yasien, A. and Bassuoni, M. T. “Properties of Nano-silica-Modified Concrete Cast and Cured under Cyclic Freezing/Low Temperatures”, Advances in Civil Engineering Materials, Vol. 8, No. 3, 2019, pp. 287-306. | en_US |
| dc.identifier.citation | Yasien, A., Abayou, A. and Bassuoni, M. T. "Performance of Nano-Modified Concrete under Freezing and Low Temperatures" Fifth International Conference on Sustainable Construction Materials & Technologies, Kingston University, London, United Kingdom, Paper #5054, 14-17 July, 2019. | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/35119 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Concrete, Cold weather, Nano-silica, Phase change material, Cold weather admixture system | en_US |
| dc.title | Cold weather concrete: innovative mixtures designs and protection methods | en_US |
| dc.type | doctoral thesis | en_US |
| local.subject.manitoba | yes | en_US |