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为深入认识施工期顺层边坡变形与应力调整规律,开展了不同开挖与锚固过程顺层边坡地质力学模型试验,分析了边坡不同部位对不同开挖坡率、锚固次序等施工过程的力学响应规律。试验结果表明:(1)顺层边坡开挖响应主要受卸荷回弹与层面滑移影响,卸荷回弹效应由开挖方量控制,层面滑移对开挖振动响应显著;开挖后边坡上部主要表现为结构面滑动变形,中部及下部主要表现出卸荷回弹特征。(2)测点与坡面的距离直接影响测点对开挖的响应,靠近开挖面测点位移大,远离开挖面测点位移小,且边坡变形随开挖坡面变陡呈增加趋势。(3)预应力锚筋不同张拉次序会引起边坡不同的响应规律。单侧顺序张拉时,距离锚筋较远的岩体呈现受拉特征,易导致岩体中原有裂隙张开或出现新裂隙;中间到两侧对称张拉时,基本所有岩体均呈现受压特征。建议采用对称张拉次序,避免单侧张拉。
In order to understand deeply the law of slope deformation and stress adjustment during construction, the geomechanical model tests of bedding slope in different excavation and anchoring processes were carried out. The construction process of different slope slopes, anchorage order and so on The mechanical response law. The test results show that: (1) The response of ground-floor slope excavation is mainly affected by unloading rebound and plane slip, the unloading rebound effect is controlled by excavation volume, and the level slip has significant response to excavation vibration; The upper part of the slope mainly shows the sliding deformation of the structural plane, while the middle part and the lower part mainly show the unloading rebound characteristics. (2) The distance between the measuring point and the slope directly affects the response of the measuring point to the excavation. The displacement near the measuring point of the excavation face is large and the displacement away from the measuring point of the excavation face is small. The deformation of the slope changes steeply with the excavation slope Increase the trend. (3) The different tensioning sequence of prestressed anchorage tendons will cause different responses of slope. When unilaterally tensioned, the rock mass farther away from the anchorage bar exhibits tension characteristics, which easily leads to the original cracks in the rock mass or new fractures. When all the rock mass is symmetrically stretched from the middle to the both sides, Pressure characteristics. Proposed symmetrical tension order, to avoid unilateral tension.