缺陷对灌浆套筒接头连接性能影响的试验研究

Experimental Research on Influence of Defects on the Connection Performance of Grouting Sleeve Joints

选用4种不同尺寸、材质的全灌浆套筒,人为设置缺陷,通过对接头进行单向拉伸试验,研究了缺陷对不同尺寸、材质灌浆套筒接头强度和变形性能的影响。结果表明:内端部缺陷长度3d为接头钢筋拉断和钢筋拔出的临界值,当缺陷长度≤3d时,接头钢筋被拉断,且强度符合规范要求;无缺陷时,相同材质套筒,内径越大,接头对钢筋延性的影响越小;相同尺寸套筒,钢制灌浆套筒接头的抗拉强度和最大拉力下的总伸长率高于球墨铸铁接头;当缺陷长度为4d时,3种钢制套筒接头的抗拉强度和最大拉力下的总伸长率均小于球墨铸铁套筒接头。

Four kinds of full grouting sleeves from different manufacturers were selected,and the defects were artificially set,and the effects of defects on the strength and deformation performance of grouting sleeve joints of different sizes and materials were studied through uniaxial tensile tests on the joints.The results show that the length of the inner end defect 3d is the critical value of the joint reinforcement and the rebar pullout.When the defect length is less than or equal to 3d,the joint reinforcement is broken,and the strength meets the specification requirements.When there is no defect and the sleeve material is the same,the larger the inner diameter,the smaller the influence of the joint on the ductility of the steel bar.When the sleeve size is the same,the tensile strength and the total elongation under the maximum force of steel grouting sleeve joint are higher than those of the ductile iron joint.When the defect length is 4d,the tensile strength and the total elongation under maximum force of the three types of steel sleeve joints are less than those of ductile iron sleeve joints.