【摘要】 为研究自钻式锚杆在砂卵石地层中的锚固性能，开展了18根自钻式锚杆的现场拉拔试验，从极限抗拔承载力、荷载-位移曲线及界面平均粘结强度等方面进行了分析。结果表明：砂卵石地层中自钻式锚杆的极限抗拔力随锚固长度的增加而增大，当锚固长度超过一定数值后，对提高锚杆极限抗拔力的能力有所下降；在破坏荷载前，自钻式锚杆的抗拔荷载–位移曲线基本呈线性，且位移量较小，达到破坏荷载时，位移量急剧增大，荷载–位移曲线出现明显拐点；锚固体–卵石界面平均粘结强度均值为0.14 MPa，高于该地区卵石层推荐的qsk值0.11 MPa，且锚固长度约在2～4 m时，界面平均粘结强度整体处于较高值。更多还原

【Abstract】 In order to study the anchoring performance of self-drilling anchor bolts in the sandy cobble stratum, field pull-out tests were carried out to 18 self-drilling anchor bolts, and the ultimate uplift bearing capacity, load-displacement curve and interfacial average bond strength were analyzed.Results showed: The ultimate uplift bearing capacity of self-drilling anchor bolts in the sandy cobble stratum increases with the anchoring length rising. If the anchoring length exceeds a certain value, the ultimate uplift bearing capacity of self-drilling anchor bolts will decline. Before the self-drilling anchor bolts reach the failure load, the load-displacement curve is essentially linear. The small displacement will increase sharply before the self-drilling anchor bolts reach the failure load, with an obvious inflection point in the load-displacement curve. The average bond strength at the interface between anchor bolts and pebbles is 0.14 MPa, which is higher than the recommended qsk value(0.11 MPa) of the pebble stratum in this area. Moreover, when the anchorage length is about 2～4m, the interfacial average bond strength is relatively high.更多还原