摘要
针对海洋及岛礁工程建设中普通混凝土原材料供需矛盾及钢筋锈蚀问题,提出以玄武岩纤维增强复合材料(basalt fiber reinforced polymer,BFRP)筋增强海水海砂混凝土(seawater sea-sand concrete,SWSSC)短柱的方案。为研究该短柱在较大偏心荷载作用下的承压性能,以纵筋配筋率、混凝土强度等级为变化参数,偏心率取值为0.48~1.10,对8根配置BFRP纵筋的SWSSC短柱进行单调静力偏心加载试验,观测试件的失效过程和破坏形态,采集开裂荷载、峰值荷载、侧向挠度、BFRP筋应变和混凝土应变等数据。试验数据分析表明:试件均以近轴力侧混凝土压碎为破坏标志,BFRP纵筋均无破坏,BFRP筋与SWSSC间未发现滑移,截面应变基本符合平截面假定;试件具有较高承载力和较好变形能力;当偏心率为0.48~1.10时,两侧纵筋最多可分别发挥相应强度的44.1%(拉)和29.8%(压),受压纵筋对试件承载力的贡献率最高可达16.3%。基于平截面假定,推导出部分截面受压BFRP纵筋增强SWSSC短柱承载力估算式,理论计算值与试验值误差小于10%,吻合较好,可为该类偏心受压构件应用于实际工程提供参考。
In view of the contradiction between the supply and demand of raw materials of ordinary concrete and the corrosion of steel bars in marine and island engineering construction,a scheme of using basalt fiber reinforced polymer(BFRP)bars to reinforce seawater sea-sand concrete(SWSSC)eccentrically compressed stub columns was proposed.In order to study the eccentric compression behavior of stub columns under large eccentric loads,considering longitudinal reinforcement ratio and concrete strength grade as the designed parameters,the eccentricity ratio was taken as 0.48-1.10,and monotonic static loading tests were carried out on eight SWSSC stub columns with longitudinal BFRP bars.Failure process and modes of the specimens were observed.Cracking loads,peak loads,lateral deflection,strain of BFRP bars and concrete were collected.The analysis of test data indicates that all the specimens are failed due to concrete crushing of the side near axial load.No BFRP bars are broken after the failure of specimens,and slip between BFRP bars and SWSSC can not be observed.The strain distributions of column section are almost in accord with the plane section assumption.The specimens can provide sufficient bearing capacity and have good deformability.When the eccentricity ratio varies from 0.48 to 1.10,the strength utilization of BFRP bars can be up to 44.1%(tension)and 29.8%(compression)respectively.The maximum contribution of compressive bars to bearing capacity of column is to 16.3%.Based on the plane section assumption,formulas were derived to evaluate the bearing capacity of SWSSC stub column reinforced with BFRP longitudinal bars partial section compressed.The error between the calculated values and the experimental value is less than 10%,which is in good agreement and can provide reference for the application of this kind of eccentric compression members in practical engineering.
作者
郑宏宇
黄志勇
袁世杰
郁宇琪
江怀雁
ZHENG Hongyu;HUANG Zhiyong;YUAN Shijie;YU Yuqi;JIANG Huaiyan(School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of the Ministry of Education(Guangxi University),Nanning 530004,China;Hualan Design&Consulting Group Co.,Ltd.,Nanning 530029,China;School of Civil Engineering,Guangxi Polytechnic of Construction,Nanning 530007,China)
出处
《中国科技论文》
CAS
北大核心
2022年第12期1332-1339,共8页
China Sciencepaper
基金
国家自然科学基金资助项目(51968004)。
关键词
海洋混凝土结构
柱
BFRP筋
海水
海砂
偏心受压
承载力
marine concrete structure
column
BFRP bars
seawater
sea-sand
eccentric compression
bearing capacity
