扩体型锚杆的研制及其抗拔试验研究

Development of underreamed anchor and experimental study of uplift resistance

在研制锚杆机械扩孔器的基础上,进行了扩体型锚杆的工艺试验和抗拔试验研究。试验结果表明,所研制的锚杆机械扩孔器对地层具有良好的适应性;扩体型锚杆较普通锚杆的承载力平均提高20%～30%,最大为66%;扩体型锚杆的轴向应变陡降现象明显,具有显著的端承效应。

The technological and uplift tests of underreamed anchors are carried out based on the development of mechanical underreamed devices of anchorage. The results show that the mechanical underreamed device has good adaptability for geology conditions; the bearing capacity of underreamed anchor increases by 20 %-30 % on an average than that of the normal anchor, and the maximum bearing capacity increases by 66 %; the phenomena of axial strain steep dropping for underreamed anchor show the end-bearing effect of underreamed anchors obviously.