全长锚固锚杆存在连续变形承载、非连续变形承载和拉拔承载3种典型工况。为系统研究全长锚固锚杆在不同典型工况下的力学特性，利用经过验证的数值模拟方法以及开发的脱锚算法开展数值试验，分析不同连续变形量级、不同裂隙参数与不同围压拉拔条件下全长锚固锚杆的轴力与剪应力分布规律，以及脱锚对不同工况条件下锚杆力学特性的影响。研究结果表明：①在连续变形工况下，全长锚固锚杆的轴力沿杆体先增大后减小，中性点以外剪应力指向锚杆头部，逐渐减小;中性点以里剪应力指向锚杆尾部，先增大后减小。锚杆头部脱锚后，中性点向锚杆尾部转移，脱锚范围轴力与剪应力基本为0。② 在非连续变形工况下，全长锚固锚杆轴力峰值与裂隙对应。脱锚前轴力与裂隙张开位移呈正比，剪应力在裂隙位置达到峰值，向两侧呈指数衰减，但方向相反;在裂隙位置脱锚后，轴力在脱锚段保持最大值，剪应力在脱锚范围两侧达到峰值，脱锚范围两侧剪应力方向相反。③在拉拔工况下，全长锚固锚杆的初始拉拔力快速增大，渐进脱锚后拉拔力表现为锯齿形升降，完全脱锚后拉拔力迅速衰减。峰值和残余拉拔力随围压而增大。未脱锚时轴力与剪应力从锚杆头部向尾部呈指数衰减;部分脱锚时轴力在脱锚段达到最大，剪应力峰值转移至脱锚范围以里;全部脱锚后轴力沿锚杆呈线性衰减，并随围压而增大。

Fully-grouted bolts usually work under three typical conditions:continuous deformation,discontinuous deformation and pulling out.To systemically investigate the mechanical behavior of fully grouted bolts under different typical conditions,some numerical experiments are performed using verified simulation method and bolt de-bonding algorithm developed.The axial force and shear stress distribution of fully-grouted bolts under different continuous-deformation magnitudes,different fracture parameters and different pulling-out confining pressures are analyzed.The influences of de-bonding on the mechanical properties of fully-grouted bolts under different typical conditions are investigated.The results show that for fully-grouted bolt,① under continuous-deformation condition,the axial force increases first and then decreases along bolt.The shear stress is directed to the near end of the bolt outside the neutral point and gradually decreases.The shear stress points to the far end of the bolt inside the neutral point,first increases and then decreases.After de-bonding of bolt head,the neutral point is transferred to the far end.The axial force and shear stress are zero in de-bonding range.② under discontinuous-deformation condition,the peaks of axial force correspond to fractures.Before debonding,the axial force is proportional to the fracture aperture.The shear stress reaches the peak at the fracture position and decays exponentially to both sides of the peak in opposite directions.After de-bonding at fracture positions,the axial force maintains the maximum in de-bonding range,the shear stress reaches a peak and the directions of shear stress are opposite on both sides of the de-bonding range.③ under pulling-out conditions,the pulling-out force first increases rapidly,then the force shows a zigzag increase after progressive de-bonding,last the force decays rapidly after complete debonding.The peak and residual pulling-out force increase with confining pressure.The axial force and shear stress decay exponentially from the near end to the far end of bolt when no de-bonding.The axial force reaches the maximum in de-bonding range,and the peak of shear stress shifts inside the de-bonding range when partly de-bonding.The axial force decays linearly along bolt and the axial force increases with confining pressure when completely de-bonding.

1 数值模拟可行性验证及脱锚算法

   1.1 单裂隙条件下全长锚固锚杆受力分析

   1.2 验证示例与过程

   1.3 脱锚算法

2 连续变形承载工况

   2.1 数值模型建立

   2.2 模拟结果分析

3 非连续变形承载工况

   3.1 数值模型建立

   3.2 裂隙张开度的影响

   3.3 裂隙位置的影响

   3.4 裂隙数量的影响

4 拉拔承载工况

   4.1 数值模型建立

   4.2 不同围压锚杆拉拔模拟结果

5 结论