中文摘要：

节理产状及其力学性能决定了岩体的完整状态，对硐室围岩整体稳定具有重要影响。考虑硐室建设过程中原岩应力释放率、节理间距、节理倾角及硐室埋深4个因素，采用离散元UDEC程序模拟了节理硐室围岩和支护结构受力状态。结果表明：①随着原岩应力释放率的增加，衬砌结构承担的荷载趋于减小，当释放率达到某一极限值时，会引起上覆岩体节理面整体错动、垮落，衬砌结构主要承载部位由仰拱向拱顶转移；②节理间距的增大增强了岩体的完整性，有助于增强岩体自身承载性能，提高围岩整体稳定；③节理倾角决定了衬砌结构主要受力部位；④随着埋深的增加衬砌结构内力及屈服单元数量总体呈增大趋势。

英文摘要：

The occurrence and mechanics of joint generally determines the integrity of rock mass, and also influences the stability of surrounding rock significantly. This paper mainly analyzes the stress of surrounding rock and lining consider- ing four factors of release ratio of initial stress, distance of joint, integrity of joint and buried depth of tunnel in construction of tunnel with UDEC code. The results show that ：（1）the stress of lining decrease with the increasing release ratio of stress, however ,once it reaches certain value, the upper covering rock mass slides and collapses, then the main bearing position turns from invert to vault; （2）the increasing distance of joint enhances the integrity of rock mass, which improves the self- beating capacity and whole stability of surrounding rock ; （3）the inclination angle of joint influences the main beating position of lining structure ; （4）the yield elements, together with the internal force of lining structure, significantly increase with the in- crease of buffed depth.