爆炸荷载作用下洞室变形与锚杆受力分析

应用模型试验与数值计算相结合的方法,对爆炸荷载作用下锚杆根部加强加固洞室围岩的变形特征及锚杆受力性能进行了研究。结果表明,在顶爆条件下,拱顶部位岩体产生的变形要大于其它部位岩体,是加固的重点地方;在锚杆端部附近,锚杆受力以受拉为主,在根部附近,以受压为主。在拱顶爆炸荷载作用下,围岩变形特性决定了拱部锚杆的受力要大于侧墙部位锚杆的受力,这两个部位的锚杆压应变峰值和拉应变峰值均不是产生在锚杆两端的截面上,而是产生在杆体中间部位。

Tunnel Deformation and Bolt Bearing State under Explosion Load

The country rock deformation character and the bolt bearing performance under explosion condition are researched based on the model test and numerical calculation.The results show that under top explosion the arch deformation is larger than the side wall deformation,so the arch is the main point for reinforcement.The bolt head is in tension state and the bolt root in compression state.The stress in arch bolt is higher than that in side wall bolt under the arch explosion load.The peak value of tension or compression present in the middle of the bolt but not in the bolt ends.