硫酸盐侵蚀与冻融循环双重因素对混凝土耐久性的影响
发布时间：2019-04-19 21:50
【摘要】：目前在全球范围内混凝土耐久性的研究已经取得了丰硕的果实,但是也存在有一些研究的盲区,例如缺少多因素复合作用下混凝土耐久性的试验方法、劣化模型以及防治措施等。我国幅员辽阔盐碱、盐湖地区也相当广阔,特别是北方的盐碱地区气候比较恶劣,这些地区的水工建筑的劣化大部分都是双因素甚至多因素作用的结果,然而我国对于多重因素的混凝土耐久性研究较少。 本文针对以上问题进行了硫酸盐侵蚀与冻融循环双重因素的混凝土的劣化模型的分析。采用了硫酸盐侵蚀后冻融循环、冻融循环后硫酸盐侵蚀与硫酸盐侵蚀-冻融循环交替三种混凝土劣化模型分析了劣化的规律,采用相对动弹性模量和质量损失率作为试验分析的评价指标,并且引用损伤叠加效应系数k得出了三种劣化模型加速劣化效果。 通过本试验分析得出,当硫酸钠溶液的浓度大于4.7%,盐冻除了有冻融破坏之外,还有硫酸盐结晶析出对混凝土造成的物理破坏；通过前期的分析和叠加效应系数的分析认为硫酸盐侵蚀与冻融循环双因素作用不是简单的相互叠加的效应,而是1+12的超叠加效应,这两种破坏是相互促进,相互影响；硫酸盐侵蚀与冻融循环的超叠加效应可能是因为前期产生的细微网状裂纹,加速了溶液的渗入,导致了双因素作用的混凝土劣化的加速；硫酸盐侵蚀-冻融循环交替的劣化速度大于硫酸盐侵蚀后冻融循环和冻融循环后硫酸盐侵蚀。
[Abstract]:At present, the research on durability of concrete in the world has achieved rich fruits, but there are also some blind areas, such as the lack of multi-factor composite test method for durability of concrete. Deterioration model and prevention measures. China has a vast territory of salt and alkali, and the salt lake area is also quite broad, especially in the northern saline-alkali areas. The deterioration of hydraulic structures in these areas is mostly the result of the action of double factors or even multi-factors. However, there is little research on durability of concrete with multiple factors in our country. In this paper, the deterioration model of concrete with sulfate erosion and freeze-thaw cycle is analyzed. Three kinds of deterioration models of concrete such as freezing-thawing cycle after sulfate erosion, sulfate erosion and sulfate erosion-freeze-thaw cycle alternation after freezing-thawing cycle were used to analyze the deterioration rule. The relative dynamic elastic modulus and mass loss rate are used as the evaluation indexes for the experimental analysis, and the accelerated deterioration effects of three degradation models are obtained by using the damage superposition effect coefficient k. According to the analysis of this experiment, when the concentration of sodium sulfate solution is more than 4.7%, there is not only freeze-thaw damage, but also physical damage caused by sulfate crystallization precipitation. Through the previous analysis and the analysis of superposition effect coefficient, it is concluded that sulfate erosion and freezing-thawing cycle double-factor action is not a simple superposition effect, but a super-superposition effect of 112. These two kinds of damage are mutual promotion and mutual influence. The supersuperposition effect of sulfate erosion and freeze-thaw cycle may be due to the micro-reticulated cracks produced in the early stage, which accelerate the infiltration of the solution and lead to the acceleration of deterioration of the concrete under the action of double factors. The degradation rate of sulfate-freeze-thaw cycle is higher than that of freeze-thaw cycle after sulfate erosion and sulfate erosion after freezing-thawing cycle.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU528
本文编号：2461316
[Abstract]:At present, the research on durability of concrete in the world has achieved rich fruits, but there are also some blind areas, such as the lack of multi-factor composite test method for durability of concrete. Deterioration model and prevention measures. China has a vast territory of salt and alkali, and the salt lake area is also quite broad, especially in the northern saline-alkali areas. The deterioration of hydraulic structures in these areas is mostly the result of the action of double factors or even multi-factors. However, there is little research on durability of concrete with multiple factors in our country. In this paper, the deterioration model of concrete with sulfate erosion and freeze-thaw cycle is analyzed. Three kinds of deterioration models of concrete such as freezing-thawing cycle after sulfate erosion, sulfate erosion and sulfate erosion-freeze-thaw cycle alternation after freezing-thawing cycle were used to analyze the deterioration rule. The relative dynamic elastic modulus and mass loss rate are used as the evaluation indexes for the experimental analysis, and the accelerated deterioration effects of three degradation models are obtained by using the damage superposition effect coefficient k. According to the analysis of this experiment, when the concentration of sodium sulfate solution is more than 4.7%, there is not only freeze-thaw damage, but also physical damage caused by sulfate crystallization precipitation. Through the previous analysis and the analysis of superposition effect coefficient, it is concluded that sulfate erosion and freezing-thawing cycle double-factor action is not a simple superposition effect, but a super-superposition effect of 112. These two kinds of damage are mutual promotion and mutual influence. The supersuperposition effect of sulfate erosion and freeze-thaw cycle may be due to the micro-reticulated cracks produced in the early stage, which accelerate the infiltration of the solution and lead to the acceleration of deterioration of the concrete under the action of double factors. The degradation rate of sulfate-freeze-thaw cycle is higher than that of freeze-thaw cycle after sulfate erosion and sulfate erosion after freezing-thawing cycle.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU528
【参考文献】
相关期刊论文 前10条
1 申春妮,杨德斌,方祥位,张涛;混凝土硫酸盐侵蚀试验方法研究[J];四川建筑科学研究;2005年02期
2 侯景鹏,史巍,刘华新;损伤力学在混凝土强度分析中的应用[J];东北电力学院学报;2000年02期
3 王铁成,杨建江;混凝土结构裂缝状态及其扩展的分形几何解析[J];大连理工大学学报;1997年S1期
4 冷发光;马孝轩;田冠飞;;混凝土抗硫酸盐侵蚀试验方法[J];东南大学学报(自然科学版);2006年S2期
5 余红发,孙伟,武卫锋,杨山,鄢良慧;普通混凝土在盐湖环境中的抗卤水冻蚀性与破坏机理研究[J];硅酸盐学报;2003年08期
6 夏宁,任青文,朱正华;基于模糊聚类的构件耐久性评估[J];工业建筑;2005年05期
7 牛荻涛，，王庆霖，王林科;锈蚀开裂前混凝土中钢筋锈蚀量的预测模型[J];工业建筑;1996年04期
8 卢木;混凝土耐久性研究现状和研究方向[J];工业建筑;1997年05期
9 郭院成,霍达;基于频率禁区约束准则的耐久性分析[J];工业建筑;1999年02期
10 陈海斌,牛荻涛,浦聿修;应用人工神经网络技术评估混凝土中的钢筋锈蚀量[J];工业建筑;1999年02期
相关博士学位论文 前1条
1 王振波;混凝土温度损伤模型研究[D];河海大学;2001年
本文编号：2461316
本文链接：https://www.wllwen.com/kejilunwen/sgjslw/2461316.html
