摘要
为了研究混凝土材料非均匀特性对保护层锈裂行为的影响,基于蒙特卡罗方法建立了随机骨料模型,采用Matlab软件编写了骨料生成和投放代码,并考虑了界面层的影响.通过改变锈蚀层厚度,对钢筋锈胀引发的混凝土保护层开裂行为进行了细观有限元模拟.结果表明,混凝土内钢筋锈蚀产物膨胀具有非均匀性,砂浆与骨料的界面是钢筋混凝土保护层锈胀过程中的最薄弱环节.当锈蚀层的最大厚度为1.24μm时,界面开始产生裂缝,随后钢筋周围砂浆产生裂缝;当锈蚀层的最大厚度为9.00μm时,混凝土保护层表面出现裂缝,此时钢筋的有效锈蚀率仅为0.186%;当锈蚀层的最大厚度达到18.00μm时,混凝土中钢筋之间裂缝贯通,此时裂缝分布图与实测锈胀开裂相似,表明细观模拟计算可靠.
To study the influence of nonuniform characteristics of concrete on the corrosion-induced concrete cover cracking,a random aggregate model was established by using the Monte Carlo method. The codes of the aggregate generation and the delivery were compiled by the Matlab software considering the influence of the interface layer. By changing the thickness of the corrosion layer,the meso-scale finite element simulation of the corrosion-induced cracking behavior caused by corrosion of steel reinforcement was conducted. The results showthat the expansion of steel reinforcement corrosion product is nonuniform. The interface layer between the mortar and the aggregate is the weakest link in the corrosion process of reinforced concrete cover. When the maximum thickness of the corrosion layer is 1. 24 μm,the interface layer begins to crack and then the mortar around the steel reinforcement cracks. When the maximum thickness of the corrosion layer is 9. 00 μm,the cracks appear on the surface of the concrete cover and the effective corrosion ratio of steel reinforcement is only 0. 186%. When the maximum thickness of the corrosion layer reaches to 18. 00 μm,the cracks between the steel reinforcement in the concrete are connected,and the crack distribution pattern is similar to that of the measured corrosion cracking,indicating that the meso-scale simulation is reliable.
作者
徐亦冬
郑颖颖
杜坤
胡雷
Xu Yidong Zheng Yingying Du Kun Hu Lei(Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China Hangzhou Traffic Investment and Construction Management Co. , Ltd. , Hangzhou 310015, China School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China)
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第2期356-361,共6页
Journal of Southeast University：Natural Science Edition
基金
"十二五"国家科技支撑计划资助项目(2015BAL02B03)
浙江省自然科学基金资助项目(LY15E080025)
关键词
钢筋锈蚀
锈胀开裂
细观模拟
随机骨料模型
steel corrosion
corrosion-induced cracking
meso-scale simulation
random aggregate model
