考虑钢筋偏心影响的铸造半灌浆套筒连接性能试验研究

Experimental study on connection performance of cast semi-grouted sleeve considering influence of rebar eccentricity

为研究钢筋偏心(垂直偏心和斜向偏心)对铸造半灌浆套筒连接性能的影响,设计制作了18个铸造半灌浆套筒连接试件,通过拉伸试验研究钢筋偏心对试件破坏形态、强度与变形性能、灌浆料损伤程度的影响。结果表明,钢筋垂直偏心和斜向偏心对接头极限承载力影响较小,主要影响接头的变形性能,且出浆口所在截面为最危险截面;钢筋垂直偏心使贴近钢筋一侧筒壁应变大于另一侧对称位置应变,且钢筋斜向偏心试件具有相同的应变分布规律;钢筋居中试件灌浆料损伤深度最小,斜向偏心试件损伤深度最大,垂直偏心试件次之。最后,建立了铸造半灌浆套筒连接接头极限承载力分析模型,接头极限承载力计算结果与试验结果吻合良好,误差小于10%。

In order to study the influence of rebar eccentricity(vertical eccentricity and oblique eccentricity)on the connection performance of cast semi-grouting sleeve,18 cast semi-grouting sleeve connection specimens were designed and fabricated,and the influence of rebar eccentricity on the failure modes,strength and deformation properties,damage degree of grout were studied by tensile test.The results show that the vertical eccentricity and oblique eccentricity of the rebar have little influence on the ultimate bearing capacity of the splices,which mainly affect the deformation performance of the splices,and the section where the slurry outlet located is the most dangerous section.The vertical eccentricity of the rebar makes the strain of the cylinder wall close to the rebar larger than that of the symmetrical position on the other side,and the rebar oblique eccentric specimens have the same strain distribution law;The damage depth of grout of rebar centered specimen is the smallest,that of oblique eccentric specimen is the largest,and that of vertical eccentric specimen is the second.Finally the analytical model was established to predict the ultimate bearing capacity of cast semi-grouted sleeve connection splices.The calculated results of the splices are in good agreement with the experimental results,and the error is less than 10%.