预紧力锚杆作用下锚固体内应力及锥形体特征分析
Analysis of Stress and Conical Body Characteristics of Anchorage Body Under the Action of Pretensioned Bolt
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摘要: 在煤矿巷道预应力锚杆支护中，锚固体内锥形体的形成是预应力锚杆能发挥作用的重要原因。为了研究预应力锚杆作用下锚固体内的应力分布和锥形体的形成规律，采用ANSYS有限元分析软件，建立了含有单根锚杆的锚固体模型，并施加锚杆预紧力和围岩压力，研究了含预应力锚杆的锚固体内应力状态和锥形体的形成规律。结果显示：锚固体内的水平应力呈现出两头大中间小的“凹”形；锚固体内锥形体呈中空的“拳头”状；在靠近锚杆端部位置，锚固体内会产生一定的拉应力；锥形体轮廓与锚杆的夹角随着围压的增大而减小，随锚杆预紧力的增大而增大；锥形体端部高度随围压的增大而增大，随锚杆预紧力的增大而减小。Abstract: In the support of prestressed anchor in coal mine roadway, the formation of cone body in anchorage body is an important reason for prestressed anchor to play a role. In order to investigate the formation laws of the conical body in the anchorage body, ANSYS was used to build anchorage body model containing a single anchor bolt. Then, pre-tightening force and surrounding rock pressure were applied on the anchor bolt and conical body respectively. The stress state inside the anchorage body and the formation of the conical body were studied. The results show that the horizontal stress inside the anchorage body shows a concave shape, i.e., the horizontal stress is higher in both end surfaces of the anchorage while that is smaller in the middle of the anchorage body. The conical body shows a “fist” shape. In some areas near the end of the anchor bolt, the anchorage body is subjected to tensile stress. The angle between the contour line of the conical body and the anchor decreases with the increase of the surrounding stress while that increases with the increase of the pre-stress. However, the height of the surface of the conical body increases and decreases with the increase of the surrounding press and pre-stress separately.
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Keywords:
- anchorage body /
- anchor bolt support /
- pre-stress /
- stress distribution /
- conical body /
- roadway support
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[1] 牛双建，靖洪文，张忠宇，等.深部软岩巷道围岩稳定控制技术研究及应用[J].煤炭学报，2011，36（6）：914-919. [2] 李晨，苏海健，胡磊.深部极软岩巷道稳定性及支护分析[J].煤矿安全，2012，43（1）：156-159. [3] 何满潮，齐干，程骋，等.深部复合顶板煤巷变形破坏机制及耦合支护设计[J].岩石力学与工程学报，2007， 26（5）：987-993. [4] 赵洪亮，姚精明，何富连，等.大断面煤巷预应力桁架锚索的理论与实践[J].煤炭学报，2007，32（10）：1061. [5] 焦建康，郑玉晶.预紧力作用下锚固体的形成特征及影响因素分析[J].煤炭技术，2017，36（6）:52-54. [6] 韦四江，李宝富.预紧力锚杆作用下锚固体的形成与失稳模式[J].煤炭学报，2013，38（12）：2126-2132. [7] 龙景奎，刘玉田.预紧力锚杆作用下锚固体协同锚固效应试验研究[J].岩石力学与工程学报，2016（S1）：2795-2802. [8] 何强，王春丽.影响锚杆支护预紧力的因素分析与确定[J].煤炭技术，2009，28（3）：159-161. [9] 贾存华.不同预紧力锚杆锚索对围岩支护应力场影响研究[J].煤炭技术，2014，33（6）：115-116. [10] 孟波.软岩巷道破裂围岩锚固体承载特性及工程应用研究[D].徐州：中国矿业大学，2013.
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