冻融和化学侵蚀下钢纤维混凝土劣化性能研究  

Deterioration Performance Investigation on Steel Fiber ReinforcedConcrete Subjected to Freeze-thaw and Chemical Effects

作　　者：纪泳丞[1] 徐文文 张秦源 杨清海 吴俊江 贾艳敏[1] JI Yongcheng;XU Wenwen;ZHANG Qinyuan;YANG Qinghai;WU Junjiang;JIA Yanmin(School of Civil Engineering,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学土木工程学院,哈尔滨150040

出　　处：《森林工程》2021年第6期99-108,共10页Forest Engineering

基　　金：黑龙江省自然基金项目(E2017003);国家大学生创新创业训练计划项目(41111206)。

摘　　要：为提高纤维混凝土在复杂环境影响下的耐久性能,本文以C30强度混凝土为基准,选取不掺加纤维的素混凝土(0%)和不同钢纤维掺加率(1%和2%)的钢纤维混凝土,研究不同环境侵蚀条件下结构力学性能的损伤机理。选取6种代表性的环境侵蚀因素,分别为:水、冻融循环、氯化钠溶液、硫酸钠溶液、稀硫酸溶液和氢氧化钠溶液,对比分析不同侵蚀环境影响下微观结构和轴向承载力的退化规律。试验结果表明,钢纤维的掺入可以有效地提高混凝土的轴向承载力,但在不同侵蚀条件下的增长规律各不相同,在氯化钠和硫酸钠环境下钢纤维掺量为1%最佳,在冻融循环、稀硫酸和氢氧化钠环境下掺量为2%最佳。该研究成果将为预测不同侵蚀条件和周期下钢纤维混凝土的性能劣化规律提供理论依据。In order to improve the durability of concrete in complex environment and ensure the design service life of the structure,the damage mechanism of mechanical properties of steel fiber reinforced concrete with plain concrete without fiber content(0%)and different steel fiber content(1%,2%)under different environmental erosion conditions was analyzed based on C30 concrete.Six environmental factors were selected,namely:water,freeze-thaw cycle,sodium chloride solution,sodium sulfate solution,dilute sulfuric acid solution and sodium hydroxide solution.The degradation laws of microstructure and axial bearing capacity under different erosion environments were comparatively analyzed.The test results showed that the addition of steel fiber can effectively improve the axial bearing capacity of concrete,but the growth rules were different under different erosion conditions.The best content of steel fiber was 1%in the environment of sodium chloride and sodium sulfate,and 2%in the environment of freeze-thaw cycle,dilute sulfuric acid and sodium hydroxide.The research results will provide theoretical basis for predicting the performance deterioration of steel fiber reinforced concrete under different erosion conditions and periods.

关 键 词：钢纤维混凝土 环境侵蚀作用 冻融循环 微观结构 力学性能 劣化预测 耐久性 

分 类 号：U444[建筑科学—桥梁与隧道工程]