| Compared with steel bars,glass fiber reinforced plastic bars(GFRP bars)have the advantages of high tensile strength,strong corrosion resistance,good insulation,light weight and easy cutting.As a new material,GFRP Bars are more and more used in civil engineering structures.GFRP Bars have similar connection problems with steel bars in concrete engineering.In this paper,a GFRP bar connector is developed,and the design method of the GFRP bar connector is established.On this basis,the quasi-static test of GFRP reinforced concrete beam column joints with connectors is completed,and the influence of connectors on the seismic performance of beam column joints is analyzed.Finally,the GFRP with connectors is given Design method of reinforced concrete beam column joint.This paper mainly carried out the following work:(1)Considering the mechanical properties of the joint,mechanical properties of GERP bar,and its practical engineering application,a new type of GFRP bar connector is designed.It analyzes the structure,load transfer mechanism,joint strength,deformation and others of the new GFRP bar connector,and the design method of the new GFRP bar connector is obtained based on the analysis of the bonding medium,the jam bolts,the type of force applied to the joint sleeve and others,and the specific specifications of the GFRP bar connector with different diameters are given.(2)According to the existing research,8 beam-column joints of GFRP reinforced concrete were designed,including 1 specimen without connector,4 specimens with connector at the end of beam and 3 specimens with connector at the end of column.The crack development and failure modes of GFRP reinforced concrete beam-column joints under the action of quasi static load are obtained by using 8 specimens in quasi-static test.Combined with the test results,the hysteretic curve and skeleton curve are obtained,and then it analyzes the existing seismic performance index of reinforced concrete such as stiffness degradation,ductility,and energy dissipation of GFRP reinforced concrete beam-column joints.Finally,the influence law of connector configuration on seismic performance of GFRP reinforced concrete beam-column joints is obtained.(3)Combining with the performance evaluation index of the existing FRP reinforced concrete members,the comprehensive performance index is improved,and the comprehensive performance index is gained,which is based on the deformation,bearing capacity and energy.Referring to the definition of relevant safety reserve and combining with the comprehensive performance index,this paper proposes a new safety reserve.Based on the existing safety reserve,the theoretical value of comprehensive performance safety reserve and the design points of GFRP reinforced concrete beam-column joints with connectors are obtained.In line with the quasi-static test of GFRP reinforced concrete beam-column joint,the test value of safety reserve of each specimen is obtained,and it compares with the theoretical value,aiming at obtaining a reasonable connector configuration form. |
