摘要
为了研究混凝土结构在不同浓度硫酸盐长期侵蚀环境下的性能劣化特征,依托某铁路路基工程低热混凝土试块,采用全浸泡法,开展混凝土在不同浓度硫酸盐(2%、5%、10%、15%)溶液、不同时长(30 d、60 d、120 d、180 d、240 d)下的抗侵蚀性能试验,分析试块侵蚀后质量变化特征及力学性能演化规律。研究结果表明,硫酸盐浓度越高,侵蚀时间越长,混凝土结构损伤劣化程度越大;侵蚀超过120 d后试块物理力学性能显著降低;受盐结晶与侵蚀作用转化,试块质量及抗压强度均呈先增大后减小的变化趋势,120 d抗压强度相较于30 d最高提升29.4%,并随侵蚀时间延长,抗压耐蚀性能整体下降,耐蚀系数最低降至0.92。由此可见,低热水泥混凝土在长时间硫酸盐侵蚀作用下耐久性能降低,研究成果可为腐蚀环境中混凝土结构耐久性评价提供重要参考依据。
To investigate the performance degradation characteristics of concrete structures under long-term sulfate erosion environments with varying concentrations,this study conducted anti-erosion performance tests on low-heat concrete specimens from a railway subgrade project using the full immersion method.Specimens were immersed in sulfate solutions with different concentrations(2%,5%,10%,15%)for varying durations(30 d,60 d,120 d,180 d,240 d).Post-erosion mass variation characteristics and mechanical property evolution patterns were systematically analyzed.Key findings reveal that:higher sulfate concentrations and prolonged erosion durations exacerbated structural damage and degradation.Physicalmechanical properties of specimens exhibited significant deterioration after 120 days of erosion.Due to the transition between salt crystallization and erosion mechanisms,both mass and compressive strength initially increased and then decreased.Compared to 30-day results,the 120-day compressive strength showed a maximum increase of 29.4%,while the corrosion resistance coefficient gradually declined with prolonged exposure,reaching a minimum of 0.92.The results demonstrate that low-heat cement concrete experiences reduced durability under prolonged sulfate attack.The research outcomes provide critical references for durability assessment of concrete structures in corrosive environments.
作者
刘志成
钟志彬
刘宏
崔凯
吕蕾
周其健
LIU Zhicheng;ZHONG Zhibin;LIU Hong;CUI Kai;LYU Lei;ZHOU Qijian(School of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;Chengdu Construction Engineering Third Construction Co.,Ltd.,Chengdu 610056,China;School of Civil Engineering,Southwest Jiaotong University,Chendu 610031,China;Chengdu Construction Engineering Group Co.,Ltd.,Chengdu 610014,China;Chengdu Construction Engineering Road and Bridge Construction Co.,Ltd.,Chengdu 610073,China;China Southwest Geotechnical Investigation and Design Institute Co.,Ltd.,Chengdu 610093,China)
出处
《铁道勘察》
2025年第2期59-65,共7页
Railway Investigation and Surveying
基金
国家自然科学基金项目(42293353,42293350)
四川省自然科学基金项目(2022NSFSC0403)。
关键词
铁路
低热水泥
混凝土
硫酸盐侵蚀
抗压强度
耐蚀系数
railway
low heat cement
concrete
sulfate corrosion
compressive strength
corrosion resistance coefficient
