摘要
通过改变冻融循环次数,研究了陶砂取代率对陶粒混凝土力学性能及抗冻性能的影响规律,测得并分析了相应阶段的抗压损失率、抗折强度损失率、质量损失率和动弹性模量损失率。以相应的损失率作为损伤变量,对表现最优的陶粒混凝土组建立相应的冻融损伤模型,并建立寿命预测模型对各个地区的陶粒混凝土抗冻性进行寿命预测。研究结果表明:随着冻融循环次数增加,表现最好的是陶砂取代率为30%时的陶粒混凝土组,该组陶粒混凝土经过120次冻融循环后,抗压强度损失率和抗折强度损失率分别为21.7%和24.5%,强度分别为37.8MPa和5.1MPa,已经超过大部分普通混凝土。陶粒混凝土的损失率(抗压和抗折强度损失率)变化和动弹性模量损失率变化比较一致,而陶粒混凝土的质量呈现先增后减,故根据动弹性模量损失率建立的冻融损伤模型可以更直观反应陶粒混凝土性能变化,寿命预测模型的建立可以为以后的相关研究提供依据。
By changing the number of freeze-thaw cycles,the influence of ceramic sand replacement rate on the mechanical properties and frost resistance of ceramsite concrete was studied,and the compressive loss rate,flexural strength loss rate,mass loss rate and dynamic elastic modulus loss rate at corresponding stages were measured and analyzed.Taking the corresponding loss rate as the damage variable,the corresponding freeze-thaw damage model is established for the ceramsite concrete group with the best performance,and the life prediction model is established to predict the life of ceramsite concrete frost resistance in various regions.The results show that with the number of freeze-thaw cycles increasing,the best performance is the ceramsite concrete group when the replacement rate of ceramsite is 30%.After 120 freeze-thaw cycles,the loss rate of compressive strength and flexural strength of this group of ceramsite concrete are 21.9%and 24.3%,respectively,and the strength is 37.7 MPa and 5.1 MPa,which has exceeded most of ordinary concrete.The change of loss rate(compressive and flexural strength loss rate)of ceramsite concrete is consistent with that of dynamic elastic modulus loss rate,while the quality of ceramsite concrete increases first and then decreases.Therefore,the freeze-thaw damage model established based on dynamic elastic modulus loss rate can more directly reflect the change of ceramsite concrete performance,and the establishment of life prediction model can provide a basis for future relevant research.
作者
倪允忠
梁汝鸣
葛序尧
刘洋
都成成
NI Yunzhong;LIANG Ruming;GE Xuyao;LIU Yang;DU Chengcheng(Design and Research Institute of The Second Construction Company of China Construction Eighth Engineering Division,Jinan 250014,China)
出处
《建筑结构》
北大核心
2023年第S01期1574-1579,共6页
Building Structure
关键词
陶粒混凝土
陶砂取代率
基本性能
损伤模型
寿命预测模型
ceramsite concrete
replacement rate of ceramic sand
basic performance
damage model
life prediction model
