FRP锚杆在石膏岩隧道中的支护效果研究

Study on Supporting Effect of FRP Bolt in Gypsum Rock Tunnel

当前穿越石膏层的隧道工程越来越多,因石膏岩具有遇水膨胀、腐蚀性等危害,传统钢锚杆支护效果不理想。FRP锚杆具有轻质高强、耐腐蚀、工艺性优良等特点,将其应用于石膏岩隧道中能够克服钢锚杆劣势。以某穿越石膏层公路隧道为依托,重点研究了FRP锚杆与传统锚杆在石膏岩隧道中的支护效果,从围岩变形、锚杆受力情况、塑性区分布、初期支护应力分布、岩体安全度等方面,对其支护效果进行对比。研究结果表明:在遇水膨胀的石膏岩中,FRP锚杆在控制围岩变形、改善塑性区分布、减少应力集中等方面优于传统锚杆,尤其是在长期运营条件下,耐腐蚀的FRP锚杆可代替传统钢锚杆作为新型支护材料应用于石膏层隧洞支护中。

At present,there are more and more tunnel projects through gypsum layer,but the traditional steel bolt support effect is not ideal because gypsum rock has the harm of water swelling and corrosiveness.FRP bolt has the characteristics of light weight,high strength,corrosion resistance and excellent technology,and can overcome the disadvantages of steel bolt when it is used in gypsum rock tunnel.In this paper,based on a through the plaster layer of highway tunnel,the research is mainly focused on the traditional FRP bolt and anchor in the gypsum rock tunnel supporting effect,from the surrounding rock deformation,bolt stress distribution,plastic zone distribution,stress distribution,degree of safety of rock mass,the primary support,etc.Comparing the supporting effect,the research results show that in the expansion of the gypsum rock under the influence of water,FRP bolt is better than traditional bolt in controlling surrounding rock deformation,improving plastic zone distribution and reducing stress concentration.Especially in long-term operation conditions,corrosion-resistant FRP bolt can replace traditional steel bolt as a new supporting material for gypsum tunnel support.