PSI - Issue 30

A.A. Kychkin et al. / Procedia Structural Integrity 30 (2020) 64–70

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A.A.Kychkin et al / Structural Integrity Procedia 00 (2019) 000 – 000

increase of glass transition temperature for 2- 3°С relative to those exposed in Yakutsk.

Fig. 5. Dependence of BFRP tensile strain after exposure in extremely cold climate Ø6 mm «1», Ø8 mm «2», in moderate warm marine climate Ø6 mm «3», Ø8 mm «4».

Linear thermal expansion of BFRP rebars showed a change of 6 % for Ø6mm and 20% for Ø8mm which might be a manifestation of failure in the surface layer that affected diffusion of moisture and be due to plasticization of the

polymer matrix. 4. Conclusions

1. The exposure of BFRP rebars to different climate conditions showed that the appearance of the samples exposed to moderate warm climate (Geledzhik) was subject to more change than those in a very cold climate (Yakutsk). The samples exposed in Gelendzhik demonstrate more intense lightening, loss of shine, and breakage of the light braiding thread. 2. Strength and maximum force for bending of the tested samples increased with longer exposure time in different climatic conditions. 3. The samples exposed to moderate warm marine climate demonstrated an increase in elastic modulus and glass transition temperature. 4. The results of thermal physical studies suggest high stability of BFRP rebars for thermal expansion. Acknowledgements The reported study was funded by RFBR according to the research project № 18 -29-05012. References Cao S and Wu Z.,2008. Tensile properties of FRP composites at elevated and high temperatures. J Appl Mech; 11: 963 – 970. Davalos JF, Chen Y and Ray I., 2011. Long-term durability prediction models for GFRP bars in concrete environment. J Compos Mater; 46: 1899 – 1914., Dong Z, Wu G, Zhao X-L, et al., 2018. Durability test on the flexural performance of seawater sea-sand concrete beams completely reinforced with FRP bars. Constr Build Mater, 192: 671 – 682. Fedorov Yu.Yu., Babenko F.I. , Gerasimov A.A., Lapii G.P., 2016. Research into effects of cold climates on mechanical properties of composite rods made from glass and basalt plastics. Industrial and Civil Construction, 8. 30-32. Jiang X, Kolstein H and Bijlaard FSK, 2012. Moisture diffusion and hygrothermal aging in pultruded fibre reinforced polymer composites of bridge decks. Mater Design, 37: 304 – 312. Kychkin A.A., Kychkin A.K., Tuisov A.G., 2015. Development and characterization of composite basalt reinforced plastic rebars. In: Science and Education 4(80): 77-81. (In Russian) Lebedev M.P., Startsev O.V.,Kychkin A.K., 2020. The Effects of Aggressive Environments on the Mechanical Properties of Basalt Plastics.