冻融环境下TRC加固RC柱轴压性能的研究  

Axial Capacity of RC Columns Strengthened with Textile-Reinforced Concrete under Freeze-Thaw Cycles

作　　者：李耀[1,2] 尹世平[1,2] 彭驰[2] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [2]中国矿业大学力学与土木工程学院江苏省土木工程环境灾变与结构可靠性重点实验室,江苏徐州221116

出　　处：《应用基础与工程科学学报》2017年第3期535-545,共11页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(51478458);中国博士后基金特别资助项目(2014T70559)

摘　　要：为探究冻融环境下纤维编织网增强混凝土(TRC)加固钢筋混凝土(RC)柱的轴压性能,本文开展了冻融循环次数、轴压应力和冻融循环耦合作用及短切纤维改性细粒混凝土等因素对TRC加固RC柱性能的研究.试验结果表明:冻融循环次数超过一定次数(20次),会造成TRC表面萌生细微的收缩裂缝,开始降低TRC约束效果,在冻融循环60次时,TRC加固RC柱的承载力降低达21.75%;轴压应力与冻融循环的耦合作用降低TRC加固RC柱的承载力及约束能力相对明显,轴压应力比率为0.4的试件的破坏形态发生改变;在TRC中掺入短切纤维可提高TRC加固柱的抗冻性.此外,掺入AR短切纤维的TRC在冻融环境下有助于提高加固柱的承载力,而掺入PVA短切纤维的TRC有助于增强加固柱的变形性能.In order to study the axial capacity of RC columns strengthened with textile-reinforced concrete （TRC） under freeze-thaw cycles, this paper took the freeze-thaw cycles, the coupling effect of sustained axial load and freeze-thaw cycles, and short-cut fibers added into fine grained concrete into account. The experimental results indicated that when the number of freeze-thaw cycles was over a certain value （20 times）, the slight shrinkage cracks appeared on the TRC＇ surface, reducing the confinement effect of TRC, and when the number of freeze-thaw cycles was up to 60,the bearing capacities of TRC-strengthened RC columns reduced about 21.75%. The bearing capacities and confining abilities reduced apparently under the coupling effect of axial load and freeze-thaw cycles, and the failure mode of specimens whose sustained axial compressive stress was 0. 4 changed. Adding the short-cut fibers into fine grained concrete could improve the frost resistance of columns. Besides, the addition of AR-glass short-cut fibers to TRC could improve the columns＇ bearing capacities and adding the PVA short-cut fibers to TRC could enhance the deformation performance of columns.

关 键 词：纤维编织网增强混凝土(TRC) 冻融循环次数 轴压应力与冻融循环耦合 短切纤维 轴压性能 

分 类 号：TU375[建筑科学—结构工程]