安全型压力分散锚索设计及在地铁车站中的应用

Design of Safe Pressure-Dispersion Anchor Cable and Application in Subway Station Construction

摘要: 本文设计了一种新的安全型压力分散锚索，该锚索在重庆市轨道交通四号线头塘地铁车站岩体支护体系中进行了应用，根据现场监测数据表明，该锚索能有效控制了车站围岩的稳定性和岩层蠕滑，并分析了锚索的张拉和锁定、预应力大小、材料松弛、施工因素对预应力损失的影响，锚索预应力的变化分为快速损失、波动变化、平稳变化三个阶段。根据锚索预应力损失和变化规律，针对不同的影响因素提出了合理选择材料、设备，选择适当的张拉方式，适当提高张拉锁定值等措施来补偿锚索预应力的损失。实践表明，所发明的锚索可以在岩土工程领域中推广应用。

Abstract: A new designed technique of safe pressure-dispersion anchor cable is introduced in this paper, and successfully applied in TouTang Subway Station project of Chongqing 4 line rail transportation. According to the field monitoring data, the anchor cable can effectively control the surrounding rock stability and rock creep slip. The influence on pre-stress loss by situation of anchor cable stretching and locking, magnitude of pre-stress, the slack of the material and construction condition was analyzed. The results showed that change of the pre-stress after stretching and locking can be divided into three stages: rapid loss stage, fluctuation change stage and steady change stage. According to the analysis of the loss and variation of pre-stressing of anchor cable, optimized combination of type of material and equipment, stretching and locking method and locking value can be obtained in order to compensate for pre-stress loss. The practices have provided valid evidence for the application of safe pressure-dispersion anchor cable technique in geotechnical engineering field.