粉煤灰陶粒轻骨料混凝土循环受压力学性能试验研究  

Cyclic Compressive Mechanical Performance of Fly Ash Ceramsite Lightweight Aggregate Concrete

作　　者：晏方 陈宇良[1,2] 陈宗平 刘杰[1] 黄芳玮 YAN Fang;CHEN Yuliang;CHEN Zongping;LIU Jie;HUANG Fangwei(College of Civil Engineering and Architecture,Guangxi University of Science and Technology,Liuzhou 545006,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China)

机构地区：[1]广西科技大学土木建筑工程学院,柳州545006 [2]广西大学工程防灾与结构安全教育部重点实验室,南宁530004

出　　处：《硅酸盐通报》2020年第8期2615-2621,共7页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51908141);广西科技基地和人才专项(AD19110068);广西自然科学基金(2019GXNSFBA245030);广西高校中青年教师科研基础能力提升项目(2019KY0361);广西重点实验室开放课题项目资助(2019ZDK038);广西科技大学研究生教育创新计划项目(GKYC202008)。

摘　　要：以强度等级、陶粒预湿时间为变量,设计制作6组陶粒轻骨料混凝土试件进行循环轴压试验,研究粉煤灰陶粒混凝土的力学性能。试验观察了试件破坏形态,获取了试件全过程应力-应变曲线及力学特征参数,深入分析了混凝土强度等级、陶粒预湿时间对陶粒轻骨料混凝土峰值应力、塑性应变、刚度退化及能量耗散的影响规律。研究结果表明:陶粒轻骨料混凝土在循环荷载作用下主要发生竖向劈裂的脆性破坏;随着陶粒预湿时间的增长,试件峰值强度有所提高,但增幅不大;试件塑性应变随循环加载次数增加而增长,混凝土强度等级、骨料预湿时间对其影响不大,采用了幂函数对标准化塑性应变与标准化循环峰值应变的关系进行了拟合,效果良好;轻骨料强度等级越高,刚度退化过程越为缓慢,能量耗散降低;循环加载末期,所有试件能量耗散随着加载次数增加而呈幂函数形式降低。To study the mechanical performance of fly ash ceramsite concrete,six groups of ceramsite lightweight aggregate concrete specimens were designed and tested under cyclic axial compression,concrete strength grade and ceramsite pre-wetting time as parameters.Failure patterns of specimens were observed,stress-strain curves and mechanical characteristic parameters of specimens were obtained,the influences of concrete strength grade and ceramsite pre-wetting time on peak stress,plastic strain,stiffness degradation and energy dissipation of ceramsite lightweight aggregate concrete were analyzed.The results show that the failure pattern of fly ash ceramsite lightweight aggregate concrete under cyclic loading occurs vertical splitting and belongs to brittle failure.With the increase of ceramsite pre-wetting time,the peak strength of the specimen slightly increases.Plastic strain of specimen increases with the increase of the cyclic loading times,and the concrete strength grade and aggregate pre-wetting time have little effect on it.The relationship between the normalized plastic strain and normalized cyclic peak strain is fitted appropriately by using power function.The higher the lightweight aggregate strength grade,the slower the stiffness degradation and the lower energy dissipation.At the end of cyclic loading,the energy dissipation decreases as a power function with the increase of loading time.

关 键 词：粉煤灰陶粒 轻骨料混凝土 循环荷载 力学性能 

分 类 号：TU528[建筑科学—建筑技术科学]