基于特征曲线法,建立考虑围岩刚度劣化本构模型开展不同开挖方式下隧道开挖空间变形特性研究,并与工程实际监测数据进行对比分析.结果表明:考虑刚度弱化后,三种开挖方式拱顶位移数值均增大;隧道开挖只对工作面前方20 m范围内围岩结构产生影响,对20 m范围以外影响甚微;在开挖工程中,距开挖工作面±10 m范围内拱顶围岩位移变化最大;为了有效控制围岩变形,开挖方式的优先顺序依次是中隔壁方式、预留核心土和台阶法;与未考虑刚度弱化的经典本构模型相比,采用刚度弱化本构模型计算得到的围岩压力释放过程更符合实际情况,拱顶位移计算结果与工程现场实际监测数据更为接近.%based on the characteristic curve method,considering the stiffness degradation of surrounding rock constitutive model is established to carry out the tunnel excavation space deformation characteristics under different excavation method,and monitoring data were analyzed with the engineering practice.The results show that the displacement values of three kinds of excavation are increased after considering the weakening of rigidity.The tunnel excavation only affects the surrounding rock structure of 20m range in front of the working face,and has little impact on the 20m range.In the excavation engineering,the displacement of the arch surrounding rock was the largest in the area of the excavation working face.In order to effectively control the deformation of the surrounding rock,the priority sequence of excavation method is the middle and next door method,the core soil and step method are reserved.And not considering rigidity weakening,compared to classical constitutive model to calculate the stiffness softening constitutive model is adopted to process of surrounding rock pressure release more accord with the actual situation,vault displacement calculation results and engineering more close to the actual monitoring data.
展开▼
