带锚固板半灌浆套筒拉伸性能数值分析

Numerical Analysis of Tensile Properties of Half Grouted Sleeve With Anchor Plate

为避免半灌浆套筒连接件因黏结滑移产生的连接件失效,提出一种将锚固板应用于半灌浆套筒中的方式,以提高半灌浆套筒连接件的可靠性及力学性能。采用ABAQUS软件,考虑钢筋与灌浆料之间的黏结滑移及灌浆料塑性损伤情况,设置不同直径钢筋、有无锚固板的有限元模拟试件组,采取位移加载方式对试件组进行单调拉伸。结果表明:同一直径下,随着钢筋锚固长度增大,钢筋-灌浆料之间黏结强度增大,半灌浆套筒连接件伸长位移减小;同一锚固长度下,随着钢筋直径增大,钢筋-灌浆料之间相对滑移增大,半灌浆套筒连接件伸长位移增大,同时,增加锚固板后限制效果也更明显;增加锚固板避免了钢筋锚固长度≤8d(d为钢筋直径)时的钢筋拔出破坏形式;无锚固板连接件的钢筋-灌浆料界面的黏结作用范围有限;锚固板发挥承压作用,远离荷载端一侧的钢筋应力显著减小。因此,可以考虑通过带锚固板的方式增加半灌浆套筒连接件的性能。

In order to avoid joint failure of half grouted sleeve connection due to bond-slip,a method of applying the anchor plate in half grouted sleeve is proposed to improve reliability and mechanical properties of half-grouted sleeve connection.Using the ABAQUS software,considering the bond-slip between the steel bar and the grouting material and the plastic damage of the grouting material,a finite element simulation specimen group with different diameters of steel bars and with or without anchor plates is set up,and the specimen group is monotonically carried out by means of displacement loading.The results show that the bond strength between steel bar and grout increases and the elongation displacement of half grouted sleeve connection decreases with the increase of anchorage length of steel bar under the same diameter.Under the same length of anchorage,with the increase of steel bar diameter,the relative slip between steel bar and grouting material increases,and the elongation displacement of half grouted sleeve connection increases.At the same time,the restriction effect is more obvious with additional anchor plate.Adding the anchor plate avoids the pull-out failure mode of steel bar when the anchorage length of steel bar is equal or less than 8d(d is the diameter of steel bar).The bonding action range of steel bar-grout interface without anchor plate connection is limited.The anchor plate plays a bearing role,and the stress of the steel bar on the side away from the load end is significantly reduced.Therefore,the performance of half grouted sleeve connections can be improved by means of anchor plates.