A MODEL TEST METHOD ON ROADWAY EXCAVATION UNDER JOINTED ROCK MASS AND ITS APPLICATION

Physical model test is an important method to study the roadway stability, however, it is difficult to build similar models for jointed rock mass because of long period and complicated process. To solve the technical problem, a set of physical model test methods for roadway excavation under jointed surrounding rock are proposed and the experimental procedure is introduced in detail based on typical roadway in Jinchuan mining zone. The main conclusions can be drawn as follows: (1)A mixed pouring-bricking method was proposed. Pouring was adopted in the inner ring of the model, and bricking was used in the outer ring, which can reflect the structural characteristics of jointed surrounding rocks, and improve the test efficiency; (2)A roadway excavation device based on embedded mold and spiral traction was developed independently, which can form the roadway well and slightly disturb the model; (3)The physical model built by roadway in Jinchuan mining area can truly reproduce the structural characteristics of the prototype and fully restore the excavation conditions of the roadway, which proves the higher practicability and efficiency of the method. The paper provides a technical reference for the design and production of similar model experiments.