套筒灌浆接头黏结滑移关系的精细有限元分析

为揭示套筒灌浆连接接头中钢筋和灌浆料间的黏结滑移关系，利用DIANA 10.3有限元软件建立接头试件的肋尺度精细有限元模型，并根据有限元分析结果对接头的局部黏结滑移关系进行研究。结果表明：套筒中钢筋黏结应力沿锚固长度大致呈马鞍形分布，加载端峰值随荷载增加逐渐内移；钢筋与灌浆料间相对滑移从钢筋自由端向加载端递增，超过屈服荷载后在加载端发生激增，并逐渐向里发展；局部黏结滑移曲线大致分为5个阶段，不同锚固位置处曲线的发展趋势大致相同，但其具体路径在发展程度和曲线特征值方面有一定差异；黏结锚固位置函数沿锚固长度大致呈“M”形分布且锚固自由端峰值大于加载端，是锚固位置和相对滑移的二元函数，建议用椭圆曲线和二次曲线进行拟合。该肋尺度精细化有限元模型可用于套筒灌浆连接接头的黏结滑移本构关系的进一步研究。

Refined finite element analysis of grouted-sleeve connection on the bond-slip relationship

To reveal the bond-slip relationship between the rebar and the grout material in the grouted-sleeve connection, the rib-scale refined finite element (FE) models of the joint specimens are established using the FE software DIANA 10.3. The local bond-slip relationships of joint specimens are investigated based on the results of FE analyses. The results show that, the distribution of the rebar bond stress is roughly saddle-shaped along the anchorage length, and the peak near the loaded end transfers inwards with the increment of the load. The relative slippage between the bar and the grout increases from the rebar free end to the loaded end. As the yielding load is beyond, the relative slippage shoots up at the loaded end and develops inwards gradually. The local bond-slip curve is divided into five stages. The curves at different anchorage positions develop similarly, but their developing paths are different at the developing extent and characteristic value. The position function of the joint specimen is a binary function of the anchorage position and the relative slippage, whose function image is roughly shaped as “M”. It is suggested to fit it with the elliptic curve and the quadratic curve. The rib-scale refined FE models are capable of investigating the bond-slip constitutive models of the grouted-sleeve connections.