<p>The choice of rock-span ratio is one of the key technical problems in the planning and design of underground station with arch cover method. In view of the complex mechanical properties of bedding rock mass, this study regards the bedding rock mass as the composite material of interlayered intact rocks and bedding planes. Based on this assumption, a transverse isotropic elastic–plastic model is established. On this basis, the evaluation zone state index of bedding rock mass during excavation is put forward. The numerical simulation of conventional uniaxial test and existing model test shows that the strength prediction and failure mode of the model are in good agreement with the physical model test results, and the local safety and failure state of bedding rock mass can be identified more effectively based on the transverse isotropic elastic–plastic model and its zone state index. With varying bedding dip angles, in the arch crown failure zone, there is a very apparent deflection accompanied by bedding angle rotation. By combining the model with zone state index, the location of the potential collapse and reasonable rock-span ratio are more accurately predicted, which effectively guides the safe construction.</p>