A new energy-absorbing bolt for rock support in high stress rock masses
A new energy-absorbing bolt for rock support in high stress rock masses
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DOI：
10.1016/j.ijrmms.2010.01.005
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发表时间：
2010-04
影响因子：
7.2
通讯作者：
C. Li
中科院分区：
文献类型：
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作者：
C. Li
最近开发了一种称为D型锚杆的能量吸收岩石支护装置，以抵消地下开挖过程中发生的易爆和挤压岩石条件。螺栓是一根光滑的钢筋，沿其长度方向有沿着多个锚固件。使用水泥浆或树脂将锚固件牢固地固定在钻孔内，而锚固件之间的锚杆的光滑部分可以响应于岩石膨胀而自由变形。一个截面的失效不会影响其他截面的钢筋性能。螺栓设计为沿着整个长度充分利用螺栓材料的强度和变形能力。锚杆具有较大的承载能力和变形能力。静态拉力试验和动态跌落试验表明，在等于螺栓材料强度的载荷水平下，螺栓长度伸长14-20%，从而吸收大量能量。20 mm D螺栓的冲击平均载荷为200- 230 kN，只有一小部分载荷传递到螺栓板上。锚杆的累积吸能为47 kJ/m。D锚杆在三个深井进行了试验。现场测量表明，D型螺栓的载荷小于钢筋螺栓。本文介绍了D型锚杆的布置和工作原理，以及相应的静态、动态和现场试验结果。
An energy-absorbing rock support device, called a D bolt, has been recently developed to counteract both burst-prone and squeezing rock conditions that occur during underground excavation. The bolt is a smooth steel bar with a number of anchors along its length. The anchors are firmly fixed within a borehole using either cement grout or resin, while the smooth sections of the bolt between the anchors may freely deform in response to rock dilation. Failure of one section does not affect the reinforcement performance of the other sections. The bolt is designed to fully use both the strength and the deformation capacity of the bolt material along the entire length. The bolt has large load-bearing and deformation capacities. Static pull tests and dynamic drop tests show that the bolt length elongates by 14–20% at a load level equal to the strength of the bolt material, thereby absorbing a large amount of energy. The impact average load of a 20mm D bolt is 200–230kN, with only a small portion of the load transferred to the bolt plate. The cumulative dynamic energy absorption of the bolt is measured to be 47kJ/m. D bolts were tested in three deep mines. Filed measurements show that D bolts are loaded less than rebar bolts. This paper presents the layout and principle of the D bolt, and corresponding results from static, dynamic, and field tests.