Study On One-dimensional Eauivalent Continuum Model Of Parallel Jointed Rock Mass

With the continuous construction of underground rock mass engineering,the topic of rock mechanics has become the frontier research direction of the engineering community.There are a large number of joints in the natural rock mass,and there are many parallel jointed rock masses,which affect the stability of the rock mass.However,the energy change in the rock mass is mainly reflected by the stress wave in the form of disturbance,so it is of great engineering significance to study the attenuation and other propagation characteristics of the stress wave in the jointed rock mass.The actual research shows that the stress wave has multiple reflection and transmission phenomena when it propagates between the joints,which is difficult to accurately superimpose.The equivalent viscoelastic model can better study the one-dimensional P-wave vertical incidence problem based on the introduction of the virtual wave source concept to reflect the multiple reflection between joints.Therefore,this paper conducts research and analysis by improving the viscoelastic model.The main research conclusions are as follows:1.By deducing the constitutive relations of several main viscoelastic models and analyzing their characteristics,based on previous studies,an equivalent viscoelastic model paralleled by Maxwell model and KelvinVoiget model is proposed to study stress.The propagation law of waves between jointed rock masses,in which the virtual wave source is introduced to reflect the multiple reflection phenomenon of waves between joints.2.Based on the physical properties of the jointed rock mass,the physical meaning represented by the unknown parameters of the model is studied.By comparing with the existing equivalent viscoelastic model,the rationality of the model is verified,and the influence of each parameter on the propagation of waves in jointed rock mass is analyzed.3.The existing equivalent viscoelastic model can only analyze the equally spaced parallel jointed rock mass.On this basis,the equivalent viscoelastic model proposed in this paper is used to briefly study the nonequal spacing parallel jointed rock mass problem.The results of this paper show that the equivalent viscoelastic model with Maxwell model and Kelvin-Voiget model can analyze the propagation law of stress wave in joints well,and the unknown parameters contain specific physical meaning.In the large-scale joint research problem,considering the viscoelastic properties of the jointed rock mass,many specific analysis processes are omitted,simplifying the problem.The rationality of the model is verified by MTALAB numerical simulation,which provides a reference for studying the propagation law of stress wave in jointed rock mass.