open access

https://hdl.handle.net/2115/81122

Influence of continuous and cyclic temperature durations on the performance of polymer cement mortar and its composite with concrete

英語

Molecular weight

2019-05-01

Elsevier

Composite structures

215

214-225

Polymer cement mortar (PCM) is a widely used cementitious repairing material due to its considerable adhesive property with concrete. However, the polymers are sensitive to elevated temperatures. The behaviours of polymers and PCM at elevated temperatures (e.g., 60 degrees C) for short, moderate duration and cyclic conditions remain unknown and need to be explored. This work was aimed at studying the mechanical performance of PCM and PCM-concrete composites under the aforementioned exposure conditions. The bond strength in tension was evaluated by interfacial split tensile and flexural strength tests. A reduction in the mechanical strength of PCM was observed when exposed and tested at 60 degrees C, and the strength recovery was also observed after cooling the specimen. The cyclic temperature condition has the most detrimental influence on the mechanical behaviour of PCM and PCM-concrete interface compared to other exposure conditions. To reveal the damage mechanism, the polymers were extracted from the PCM, and the glass transition (T-g) and melting point temperatures were obtained by differential scanning calorimetry (DSC) analysis. Corresponding to the mechanical reduction of the PCM and interface, the reduction in the T-g value was also observed after elevated temperature and cyclic temperature exposure except the case exposed to moist condition. The maximum strength recovery was observed when the testing temperature was less than T-g . Besides, the molecular weight of the extracted polymers was analysed by gel permeation chromatography (GPC). The ratio of the area regarding the amount of oligomers to the area regarding the molecular weight of the GPC curve increased with the temperature duration, which was consistent with the tensile strength reduction of PCM.

学術雑誌論文

Accepted Manuscript

Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

© <2019>. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/

0263-8223