高温后纤维陶粒混凝土力学性能试验研究

通过对分别掺入聚丙烯腈纤维(PANF)、聚乙烯醇纤维(PVAF)的陶粒混凝土进行20,200,400,600,800℃五个温度水平高温后的加载试验,研究纤维掺入对陶粒混凝土抗压强度、抗拉强度与弹性模量随温度的变化规律,并与无纤维掺入陶粒混凝土进行对比分析。试验表明:分别掺入纤维PANF和PVAF后,对高温后陶粒混凝土的立方体抗压强度无明显改善效应,但可有效提高陶粒混凝土高温后的劈裂抗拉强度;掺入PANF后可改善陶粒混凝土在达到峰值极限荷载后的脆性破坏特性,在600℃内可有效提高陶粒混凝土高温后的棱柱体抗压强度,在20~400℃内能有效减缓陶粒混凝土弹性模量的降低。

EXPERIMENT OF MECHANICAL PERFORMANCE OF FIBER CERAMSITE CONCRETE AFTER ELEVATED TEMPERATURE

It was carried out that loading tests of polyacrylonitrile fiber( PANF) ceramsite concrete and polyvinyl alcohol fiber( PVAF) ceramsite concrete at 20,200 400,600 and 800 ℃ to study the change laws of the compressive & tensile strengths and elastic modulus of the ceramsite concrete with temperatures,which were also compared to the ceramsite concrete without fibers. The test results show that the cubic compressive strength of fiber ceramsite concrete is not significantly improved. However the splitting tensile strength after elevated temperature is improved effectively. PANF can improve the brittle fracture performance of ceramsite concrete at the peak loading.The residual prism compressive strength of PANF ceramsite concrete is also obviously increased when the temperature ranges from 20 ℃ to 600 ℃,and the elastic modulus of the PANF decreases more slowly when the temperature ranges from 20 ℃ to 400 ℃.