荷载-硫酸盐侵蚀作用后高强混凝土的力学特性  

MECHANICAL PROPERTIES OF HIGH-STRENGTH CONCRETE SUBJECTED TO LOADING AND SULFATE ATTACK

作　　者：逯静洲[1] 朱孔峰 田立宗[1] 国力[1] LU Jingzhou;ZHU Kongfeng;TIAN Lizong;GUO Li(School of Civil Engineering, Yantai University, Yantai 264005, Chin)

机构地区：[1]烟台大学土木工程学院

出　　处：《工业建筑》2018年第3期11-16,共6页Industrial Construction

基　　金：国家自然科学基金项目(51479174)

摘　　要：通过对经历不同荷载水平和硫酸盐浓度后的高强混凝土试件进行单轴压缩试验,研究了荷载历史及硫酸盐干湿循环侵蚀对高强混凝土抗压强度、弹性模量、峰值应变和应力-应变曲线的影响,并考虑了不同标距对应变测量结果的影响。结果表明：随单调荷载水平的增大,未侵蚀和浓度为1%侵蚀的混凝土抗压强度、弹性模量以及峰值应变减小,浓度为5%和10%侵蚀的混凝土抗压强度和弹性模量减小,而峰值应变增大;随着溶液浓度的增大,未经历荷载历史和经历单调荷载50%的混凝土抗压强度和弹性模量先增后减,峰值应变先减后增,而经历单调荷载70%和循环荷载50%的混凝土抗压强度和弹性模量减小,峰值应变增大;试件的力学性能对高浓度侵蚀较敏感,经历浓度为10%侵蚀的混凝土强度降低达25%;浓度对应力-应变曲线的影响较为显著,经历浓度为10%侵蚀的混凝土曲线上升段斜率变小,且形状变得扁平。在此基础上,利用基于Weibull分布的损伤本构模型对试验曲线进行研究,并对模型参数进行统计分析,结果表明建立的损伤本构模型理论曲线与试验曲线吻合较好。The uniaxial compressive tests were conducted on high-strength concrete specimens different load history and dry-wet cycle action of concentrations of sulfate solutions corrosion. The effects of loading history sulfate corrosion in dry-wet cycle environment on the compressive strength,elastic modulus,peak strain and stress-strain curve of concrete were investigated,and the influence of different gauge lengths on strain measured results was considered.Experimental results showed that with the increase of monotonic loading level,the compressive strength,elastic modulus and peak strain of specimens decreased without corrosion or with 1% sulfate solution,while the compressive strength and elastic modulus of specimens decreased with 5% and 10% sulfate solutions,the peak strain increasd; as the solution concentration increased,the compressive strength and elastic modulus of specimens decreased after the first increasing subjected to zero-load history and monotonic load of 50% ,the peak strain increased after the first drop,whereas the compressive strength and elastic modulus of specimens decreased subjected to monotonic loads of 50% and 70% ,the peak strain increased. The high solution concentration had a great influence on the mechanical properties,and the compressive strength of specimens was decreased by 25% subjected to 10% sulfate solution; the stress-strain curves subjected to sulfate attack changed obviously,the slope of curve at ascent stage decreased when the concrete was subjected to 10% sulfate solution,and the shape of curve became flatter. Moreover,a damage constitutive model based on Weibull distribution was selected to study the experimental curves and the model parameters were analyzed. The results showed that the theoretical curves of damage model were in good agreement with the test curves.

关 键 词：高强混凝土 荷载历史 硫酸盐侵蚀 干湿循环 本构模型 

分 类 号：TU528.31[建筑科学—建筑技术科学]