Reseach on the impact of fireproof impregnation by preservatives containing nanoparticles on the strength of construction timber in increased temperatures

摘要

In the conditions of high temperatures impact, a timber construction is subjected to simultaneous excitations in the form of forces and thermal actions. The impacts of these two factors have an effect on the distribution of stresses in the timber structure as well as limit load-bearing capacity of construction, causing the structure decohesion. The article depicts the results of experimental research on the impact of increased temperature on the strength of bent pine timber impregnated by the aqueous fireproof preservative containing nanoparticles SiO2-TiO2. Samples used for strength tests were made in the form of cuboids of dimensions 20x20x300 mm, and then they were divided into three groups. The first group consisted of natural samples, not modified. The second group was subjected to impregnation by an aqueous solution. The aqueous solution of nanoparticles Si02-Ti02 of concentration 800 ppm, in the proportion of 4 to 6. The third group of samples was impregnated by the aqueous solution on the basis of nanoparticles Si02-Ti02 of the same concentration and proportions as previous one, with the addition of wetting agent Amber One in the concentration of 0,5%. As a result of performed research, the negative influence of impregnates containing nanoparticles both in normal and increased temperature, has been observed.