养护条件对BCCP抗氯离子侵蚀性能的影响与比较分析  

Influence and Comparative Analysis of Curing Conditions on Chloride Resistance of BCCP

作　　者：胡钰泉 胡少伟 李文昊 汪旭 孙兆斌 HU Yuquan;HU Shaowei;LI Wenhao;WANG Xu;SUN Zhaobin(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China;Yellow River Laboratory,Zhengzhou University,Zhengzhou 450001,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China;Ningxia Qinglong Pipe Group Co.,Ltd.,Yinchuan 750000,China)

机构地区：[1]河海大学土木与交通学院,江苏南京210098 [2]郑州大学黄河试验室,河南郑州450001 [3]重庆大学土木工程学院,重庆400045 [4]宁夏青龙管业集团股份有限公司,宁夏银川750000

出　　处：《防灾减灾工程学报》2023年第3期559-567,共9页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金重点项目(51739008);重庆市自然科学基金创新群体项目(cstc2020jcyj-cxttX0003);重庆市技术创新与应用发展专项重点项目(cstc2019jscx-gksbx0013)资助。

摘　　要：通过测试钢筋缠绕预应力钢筒混凝土管道(BCCP)细石混凝土保护层试块在标准养护(S),低压养护(0.7P),蒸汽养护(ZS)和蒸汽-低压养护(Z0.7P)条件下的氯离子扩散系数、抗压强度和吸水率,研究养护方式对BCCP抗氯离子侵蚀能力的影响,并基于灰色关联分析法,比较各因素的影响程度。结果表明:混凝土的抗氯离子侵蚀能力随着养护龄期的增加而增加,单掺矿粉混凝土始终表现最优,使用高抗硫水泥会降低混凝土本身抗氯能力。低压和蒸汽养护的混凝土在早龄期抗氯能力高于标准养护,但随水化龄期的增长,逐渐低于标准养护。低压不会对蒸养混凝土内部产生损伤,反而会提高混凝土的密实度,因此,在养护龄期14 d以前,扩散系数关系为S>0.7P>ZS>Z0.7P,28 d以后,变为ZS>Z0.7P>0.7P>S;此外,养护气压和养护湿度对混凝土抗氯离子渗透性影响最大,其次是养护温度,养护龄期的影响最小。The chloride diffusion coefficients,compressive strength,and water absorption rates of fine aggregate concrete cover blocks of Bar-wrapped Cylinder Concrete Pressure Pipes(BCCPs)were examined under standard curing(s),low pressure curing(0.7p),steam curing(ZS),and steam-low pressure curing(Z0.7p)to study the influence of curing methods on BCCP’s resistance to chloride.The influence degree of each factor was compared using grey correlation analysis.Results show that the resistance to chloride ingress of concrete increased with the increase of curing age and the chloride resistance of concrete with single mineral powder demonstrated the best performance.The utilization of high sulfate-resistant cement will reduce the chlorine resistance of concrete.At early stages,the resistance to chloride ingress of concrete cured under low pressure(0.7P)and steam(ZS)was higher than that cured under standard conditions(S),while over time,this trend reversed.Furthermore,0.7P will not damage the interior of steam cured concrete(Z0.7P),but will improve the compactness of concrete.Therefore,the chloride diffusion coefficient of concrete is S>0.7P>ZS>Z0.7P prior to 14 days of curing age,while it will change to ZS>Z0.7P>0.7P>S after 28 days.In addition,curing air pressure and humidity have the greatest influence on the chloride ion permeability of concrete,followed by curing temperature,and curing age has the least influence.

关 键 词：钢筋缠绕预应力钢筒混凝土压力管 混凝土 养护方式 氯离子扩散系数 配合比 关联系数 

分 类 号：TV332[水利工程—水工结构工程]