摘要
根据青海盐湖地区服役环境,配置包含SO_(4)^(2-)、Cl^(-)、Mg^(2+)的盐湖卤水腐蚀溶液,将磷酸镁混凝土试件浸泡在溶液中,每隔30 d测定动弹性模量、质量作为评价指标,在磷酸镁混凝土中加入聚丙烯纤维、二氧化硅活性材料和双掺聚丙烯纤维二氧化硅改善其性能并与无添加对比分析,以相对动弹性模量作为磷酸镁混凝土耐久性退化指标,建立一元Wiener退化过程预测模型进行可靠度分析,采用极大似然法进行参数估计,建立服役寿命的可靠性函数和概率密度函数。结果表明:Wiener函数可有效刻画磷酸镁混凝土在盐湖卤水腐蚀下的退化过程,建立的可靠度函数能描述各试件的服役寿命,并且与实验结果相吻合,可靠性寿命时间依次为双掺聚丙烯纤维和二氧化硅>单掺二氧化硅>单掺聚丙烯纤维>无添加,建立的Wiener概率分布模型可反映四种类型磷酸镁混凝土的腐蚀损伤劣化规律,从而为盐湖地区磷酸镁混凝土寿命预测及耐久性评估提供可靠性依据。
According to the service environment in the Salt L.Area of Qinghai Province,The bittern corrosion solution containing SO_(4)^(2-),Cl^(-),Mg^(2+),and the magnesium phosphate concrete specimens were immersed in the solution,and the dynamic modulus of Elasticity and quality were measured every 30 days,the performance of magnesium phosphate concrete was improved by adding polypropylene fiber,silicon dioxide and polypropylene fiber silicon dioxide and compared with the concrete without adding polypropylene fiber,taking relative dynamic Modulus of Elasticity as the index of durability degradation of magnesium phosphate concrete,a one variable Wiener degradation process prediction model is established for reliability analysis,and the parameters are estimated by using maximum likelihood,establish the reliability function and probability density function of service life.The results show that the Wiener function can describe effectively the degradation process of magnesium phosphate concrete under the corrosion of Salt L.Brine,and the established reliability function can describe the service life of each specimen,and is in good agreement with the experimental results,the reliability life time is in the order of double-doped polypropylene fiber and silicon dioxide fiber>single-doped silicon dioxide>single-doped polypropylene fiber>no-additive.The Wiener probability distribution model established can reflect the corrosion damage deterioration law of four types of magnesium phosphate concrete,the results provide reliable basis for life prediction and durability evaluation of magnesium phosphate concrete in Salt L.Area.
作者
邵亚飞
李双营
Shao Yafei;Li Shuangying(School of Civil and Transportation Engineering,Qinghai Minzu University,Xining 810007,China)
出处
《青海科技》
2023年第6期189-196,共8页
Qinghai Science and Technology
