摘要
以钢纤维体积掺量和截面含钢率为主要变化参数,对23个方钢管钢纤维再生混凝土短柱和2个未掺加钢纤维的方钢管再生混凝土短柱试件进行了轴心受压试验。通过试验,观察了试件受力全过程和破坏形态,获取了荷载-位移曲线和荷载-应变曲线,并分析了钢纤维体积掺量、截面含钢率对其承载和变形性能的影响。结果表明:方钢管钢纤维再生混凝土短柱轴向受压破坏形态与方钢管普通混凝土构件相似,掺入钢纤维对其破坏形态几乎无影响;钢纤维的掺入对试件承载力的增益作用并不明显,当钢纤维体积掺量不超过1. 5%时,试件轴压承载力较未掺加钢纤维构件有小幅提高,但当钢纤维体积掺量超过2%后,因钢纤维数量增多易出现分布不均匀而结团、混凝土界面薄弱区增多,试件承载力反而降低,且降幅随钢纤维体积掺量增大而增大;掺入钢纤维显著改善了试件延性,试件位移延性系数随钢纤维体积掺量的提高而增大;截面含钢率对试件承载性能影响明显,试件承载力和位移延性系数均随截面含钢率的增大而增大;为使试件既获得较高的承载力又具有良好的延性,建议钢纤维体积掺量取为1. 0%~1. 5%;利用基于统一强度理论提出的方钢管钢纤维再生混凝土短柱的轴压承载力计算公式所得结果与试验实测数据符合较好。
Considering the steel fiber volume content and steel ratio as main variable factors,axial compression test was carried out on 23steel fiber reinforced recycled aggregate concrete-filled square steel tubular short columns and 2 recycled aggregate concrete-filled square steel tubular short columns.Through the experiment,the full loading process and failure modes of specimens were observed,the load-displacement curves and load-strain curves of specimens were obtained,the influence of the volume content and steel ratio on the bearing capacity and deformation performance was analyzed.The results showed that the failure modes of steel fiber reinforced recycled aggregate concrete-filled square steel tubular short columns were similar to that of the normal concrete filled steel tubular columns,the steel fiber had little influence on failure modes;the influence of steel fiber content were less on increasing the bearing capacity of the specimens,when the steel fiber volume content not exceeding 1.5%,the specimen bearing capacity was slightly improved,while the steel fiber volume content exceeding 2%,the specimens bearing capacity decreased as the steel fiber volume content increased,because of the steel fiber uneven distribution and could easily get together,led concrete deteriorated area worse;the ductility of the specimens significantly improved when steel fiber was added,the displacement ductility coefficient increased as the steel fiber volumetric content increasd;steel ratio had a significant influence on mechanical properties of specimens,the specimens bearing capacity and displacement ductility coefficient increased as the steel ratio increased;the steel fiber volume content were recommended between 1.0%-1.5%to get higher bearing capacity and ductility;the calculation results by using the formula of axial compression bearing capacity of steel fiber reinforced recycled aggregate concrete-filled square steel tubular short columns based on the Unified Strength Theory were in good agreement with the experimental data.The research results could provide a reference for engineering applications.
作者
张兆强
赵均海
邓勇军
ZHANG Zhaoqiang;ZHAO Junhai;DENG Yongjun(School of Civil Engineering,Chang'an University,Xi'an 710061,China;School of Civil Engineering and Arehitecture,Southwest University of Science and Technology,Mianyang 621010,China)
出处
《工业建筑》
CSCD
北大核心
2018年第11期168-174,共7页
Industrial Construction
基金
国家自然基金资助项目(51308479)
四川省科技厅资助项目(18JY0443)
四川省教育厅资助项目(18CZ0012)
绵阳市科技局项目(15S-02-3)
关键词
方钢管钢纤维再生混凝土
轴压性能
试验研究
steel fiber reinforced recycled aggregate concrete-filled square steel tubes
axial compression behavior
experimental research
