非全长粘结型锚索锚固段长度的一种确定方法

CALCULATION METHOD OF LENGTH OF ANCHORING SEGMENT FOR PARTIAL-COHESIVE CABLE

根据对锚杆拉拔试验结果的分析及对锚杆与锚索锚固段受力差异的比较,提出了非全长粘结型锚索锚固段剪应力沿长度的分布模式,并讨论了剪应力分布曲线的特征点,得到了锚固段剪应力沿长度分布为在靠近锚固段顶端有最大值而其两侧则逐渐减小的单峰曲线,提出了确定锚固段长度的合理方法,即以锚固段最大剪应力不超过经过安全储备后的地层与注浆体间的粘结强度作为控制条件。最后,以工程实例说明了锚固段长度的计算方法。

According to analysis on pulling test results of bolt and comparison of the mechanical status of anchoring segment between bolt and cable, the distribution model of shear stress along the anchoring segment of partial-cohesive cable is put forward. The shear stress reaches the maximum not right at the midpoint of anchoring segment but at side near ground surface and reduces to 0 at the ends of anchoring segment. A reasonable calculation method of the length of anchoring segment is given. The main control condition is that the maximum shear stress of anchoring segment can't exceed the value of cohesive strength divided by safety factor. The calculation method of length of anchoring segment is shown in detail by a practical example in the paper.