严寒地区隧道衬砌混凝土的冻融试验分析  

Freezing and Thawing Cycle Experimental Analysis on Lining Concrete for Tunnel in Cold Regions

作　　者：张迎辉 Zhang Yinghui(China Railway 15th Bureau Group Fifth Engineering Co. Ltd. , Tianjin 300121, China)

机构地区：[1]中铁十五局集团第五工程有限公司,天津300121

出　　处：《铁道建筑技术》2018年第3期12-15,共4页Railway Construction Technology

基　　金：中铁十五局集团有限公司科技研发计划项目(2017B04)

摘　　要：针对混凝土在轴心受压和偏心受压状态下的抗冻性问题,以C30混凝土为例、设计了0.4、0.5和0.6三种压应力水平的轴心受压试件及一种偏心受压试件,通过快速冻融循环试验来对比分析它们的抗冻性能,每隔25个冻融循环测试试件的质量和动弹性模量。试验结果表明:破坏时所有试件都达到了相对动弹性模量的限值,而没有达到质量损失限值;轴心受压试件随着应力水平的提高,冻融循环前期抗冻性能逐步增强,但后期损伤速度急剧加快;偏心受压试件与轴心受压试件的性能衰减规律相似,但由于应力的不均匀分布使其衰减曲线更平滑。结论为荷载作用下混凝土结构的抗冻性能研究提供了参考。Aiming at the frost resistance property of C30 concrete under the conditions of axial compression and eccentric compression, axial compressive specimens with three kinds of stress levels （0.4, 0.5, 0.6） and one kind of eccentric compression specimen were designed, and the freezing and thawing cycle experiments were carried out to compare their frost resistance characteristics. The mass and dynamic elastic modulus were tested every 25 freezing and thawing cycles. The experimental results show that all the specimens have reached the limit of the relative dynamic elastic modulus, but not the limit of the mass loss at the time of failure. With the increase of the stress level, the frost resistance performance of the axial compression specimen gradually increases at the early stage of the freezing and thawing cycle, but the damage speed accelerates rapidly in the later period. The attenuation law of the frost resistance performance of the eccentric compression specimen is similar to that of the axial compression specimen, but its attenuation curve is smoother because of the uneven stress distribution. This paper provides a reference for the study of the frost resistance property of concrete structures under the load.

关 键 词：受压混凝土 应力水平 抗冻性能 动弹性模量 质量损失 

分 类 号：U454[建筑科学—桥梁与隧道工程]