寒区碳纤维增强混凝土抗冻性能试验研究

研究了不同掺量的碳纤维对川藏线极温冻融环境下混凝土耐久性能的影响。通过快速水冻水融法,测试了川藏-27～40℃极温循环下碳纤维增强混凝土的抗冻指标,包括相对动弹性模量、质量损失率、失水量。结果表明,随着冻融循环次数的增加,所有试件的质量损失率在冻融前期变化一致;冻融70次后,随着碳纤维掺量的增加,质量损失率先减小后增大,掺量为0.24%时的质量损失率最小;相对动弹性模量随着掺量的增加先增大后减小,且当掺量为0.24%时达到最大;冻融过程中,碳纤维掺量对失水量的影响较小。

Experimental Study on the Frost Resistance of Carbon Fiber Reinforced Concrete in Cold Areas

The effect of different contents of carbon fibre on the durability of concrete under freeze-thaw environment of Sichuan-Tibet railway line was studied, and the rapid freeze-thaw method was used to test the frost resistance index of carbon fiber reinforced concrete(CFRC) at-27~40 ℃, including the relative dynamic elastic modulus, mass loss rate and water loss. The results show that with the increase of freeze-thaw cycles, the mass loss rate of CFRC was the same in the early stage of freeze-thaw. With the content of carbon fiber increases, the mass loss rate decreases first and then increases, and the mass loss rate is the smallest at 0.24% content after 70 times of freeze-thaw cycles. The relative dynamic elastic modulus first increases and then decreases with the increase of the content of carbon fiber, and reaches the maximum when the content is 0.24%. During the freeze-thaw process, the content of carbon fiber has little effect on water loss.