Abstract
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 °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 °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 (Tg) 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 Tg 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 Tg. 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.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.