盐湖环境下混凝土表面氯离子浓度的多因素耦合模型

Experimental study on multi-factor coupling model of concrete surface chloride concentration in salt lake

采用盐湖溶液浸泡实验,通过定期检测盐湖环境中混凝土表面处的氯离子侵蚀含量,并对数据进行拟合分析,研究了混凝土表面氯离子侵蚀含量随时间的变化规律,分析了盐湖溶液氯离子浓度、水灰比和暴露时间对混凝土表面氯离子侵蚀含量及其累积速率的影响。结果表明,盐湖环境中混凝土表面氯离子侵蚀含量随时间的增大逐渐增长并最终达到稳定状态。随着盐湖溶液氯离子浓度和水灰比的增加,盐湖环境中混凝土表面氯离子侵蚀含量将达到稳定状态,进而综合考虑水胶比、盐湖溶液氯离子浓度和时变特性等因素的影响,建立了盐湖环境下混凝土表面氯离子浓度的多因素计算模型。结合国内外各种盐湖环境中混凝土表面氯离子侵蚀含量经验模型的预测结果和本文实测数据,对比验证了所建立混凝土表面氯离子浓度计算模型的有效性和适用性,为盐湖环境下混凝土结构的耐久性设计和服役寿命分析提供了重要边界条件。

Immersion in sodium chloride solution was adopted to periodically test chloride ion concentration at the surface of concrete and regression analysis was completed.And time-dependent law of surface chloride ion concentration of concrete with time was investigated.Influences of chloride ion concentration in solution,water to cement ratio and corrosion time on bigness and accumulation rate of surface chloride ion concentration were also analyzed.Taking into account the influence of factors such as water-binder ratio,chloride ion concentration and time-varying characteristics,a multi-factor calculation model for chloride ion concentration on the concrete surface was established.Combining the prediction results of empirical models of various surface chloride ion concentrations at home and abroad and the measured data of this paper,the effectiveness and applicability of the established surface chloride ion concentration calculation model were compared and verified,and the durability design and service life of the concrete structure under cool chlorine were compared.The analysis provides important boundary conditions.