初始加载龄期对陶粒混凝土梁徐变性能的影响  

Influence of initial loading age on creep performance of ceramsite concrete beam

作　　者：朱红兵[1,2] 金伟良 李家鹏 肖宇 ZHU Hongbing;JIN Weiliang;LI Jiapeng;XIAO Yu(College of Urban Construction,Wuhan University of Science and Technology,Wuhan 430065,China;Institute of High Performance Engineering Structure,Wuhan University of Science and Technology,Wuhan 430065,China)

机构地区：[1]武汉科技大学城市建设学院,湖北武汉430065 [2]武汉科技大学高性能工程结构研究院,湖北武汉430065

出　　处：《混凝土》2024年第5期104-107,116,共5页Concrete

基　　金：国家自然科学基金(51678234)。

摘　　要：徐变性能对混凝土结构的承载性能有较大影响,初始加载龄期(养护龄期)对徐变有较大影响,基于4种不同初始加载龄期的陶粒混凝土梁,进行了为期200 d的徐变试验,研究初始加载龄期对陶粒混凝土梁徐变性能的影响规律试验研究,并建立基于ACI-209徐变计算模型和ACI-435长期挠度计算方法建立陶粒混凝土结构的徐变值计算式。结果显示:随着初始加载龄期的增加,陶粒混凝土梁的初始挠度、徐变挠度速度和最终挠度值均呈现减小的趋势,减小的幅度也随着加载龄期的延长而逐渐减弱;徐变值计算式的计算值与试验观测值较接近,所建立的计算式具有较好的准确性和适用性;综合考虑工期和经济指标,建议将90 d作为预制陶粒混凝土梁的加载龄期。研究结论可为陶粒混凝土结构徐变计算提供参考。The creep performance has a great influence on the bearing capacity of concrete structures,and the initial loading age(curing age)has a great influence on the creep.Based on the ceramsite concrete beams with four different initial loading ages,a 200 d creep test was conducted to study the effect of initial loading ages on the creep performance of ceramsite concrete beams.The creep calculation formula of ceramsite concrete structure was established based on ACI-209 creep calculation model and ACI-435 long-term deflection calculation method.The results show that with the increase of the initial loading age,the initial deflection,creep deflection velocity and final deflection of ceramsite concrete beams show a decreasing trend,and the decreasing range also decreases with the extension of the loading age.The calculated value of the creep value calculation formula is close to the experimental observation value,and the established calculation formula has good accuracy and applicability.Considering the construction period and economic indicators,it is suggested that 9od should be taken as the loading age of precast ceramsite concrete beams.The conclusions can provide reference for the creep calculation of ceramsite concrete structure.

关 键 词：陶粒混凝土梁 徐变 初始加载龄期 试验 计算模型 

分 类 号：TU528.041[建筑科学—建筑技术科学]