重庆鹅公岩大桥隧道锚碇围岩稳定性.pdfVIP

第 24 卷 增 2 岩石力学与工程学报 Vol.24 Supp.2 2005 年 11 月 Chinese Journal of Rock Mechanics and Engineering Nov.，2005 重庆鹅公岩大桥隧道锚碇围岩稳定性 肖本职，吴相超，彭朝全 (长江科学院 重庆岩基研究中心，重庆 400014) 摘要：重庆鹅公岩长江大桥设计采用悬索桥方案。东锚碇为隧道锚，布置在粉质砂岩和砂质泥岩互层岩体中，锚 碇及围岩体的变形状态直接影响大桥的稳定和安全。为了了解锚碇及围岩体在张拉荷载下的变形状态及围岩极限 承载能力，对围岩及锚碇进行了较全面的试验研究，包括岩体参数试验、1 ∶12.5 实地结构模型张拉试验、数值分 析及灰色 GM(1，1)模型预测等。研究表明：锚碇及围岩变形较小，变形处于弹性阶段；灰色 GM(1，1)预测出岩 体极限承载力为设计荷载的 6.09～6.15 倍，锚碇处于安全状态，并有足够安全储备。试验研究成果为设计提供了 可靠依据。 关键词：隧道工程；隧道锚；围岩稳定性；模型试验；预测；鹅公岩大桥 中图分类号：TV 698.1 文献标识码：A 文章编号：1000 –6915(2005)增 2 –5591 –07 STABILITY OF THE ANCHORAGE WALL ROCK OF TUNNEL FOR CHONGQING EGONGYAN BRIDGE XIAO Ben-zhi ，WU Xiang-chao ，PENG Chao-quan (Chongqing Rock Foundation Research Center，Yangtze River Scientific Research Institute，Chongqing 400014 ，China) Abstract ：The suspension bridge scheme is adopted for Chongqing Egongyan bridge. East anchorage is considered as one of anchors for tunnel anchorage，which is assigned in silty-sandstone and sand-mudstone layers. The deformation states of anchorage and wall rock have great influences on the stability and safety of the bridge directly. In order to understand the ultimate bearing capacity of wall rock and the deformation state of the anchorage and rock at tensile force，comprehensive studies are performed on the anchorage and wall rock，such as tests for the parameters of rock mass ，tensile test for tunnel anchorage model with scale 1 ∶12.5，numerical analysis，and grey GM(1，1) model forecast，etc.. The studies show that the deformation of anchorage and wall rock is smaller ，which is in the linear s