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Flexible pressurized anchor is a kind of new anchor which has new structure and unique anchoring mechanism. It has many advantages, such as, it can active adapt for the motion of adjacent rock and compensate the variable anchoring force, it can achieve the total length anchoring, the weight of anchor is light, and it can be recovered and multiple-used, etc. Through the inner pressure, the anchor extrudes the adjacent rock forming the arch pressure; provide the initiative anchoring for the adjacent rock. It overcomes the disadvantages of conventional anchor which is insufficient adhesive force, unstable anchorage, and adaptability for soft rock and large deforming tunnel. This research has important theoretical significance and use value.Author chooses theoretical analytical method of elasticity, high molecular synthetic material and rock mechanics, associates ground-based simulation with underground tests, analysis and calculate the flexible pressurized anchor’s force, deformation, and the contact analysis of the anchoring system which formed with adjacent rock, and guide the design and processing. Analyzed with the experimental results and gradually improve the structural design of anchor. The main research efforts, as follow:1. Analysis the anchoring force and anchoring mechanism of the flexible pressurized anchor from theory and experiment. Derive the calculation and analysis methods from its load-bearing capacity, and provide the theoretical basis for the design, test and application.2. Through the study of the flexible pressurized anchor’s structure characteristics, establish the physical and mathematical models, take use of the ANSYS software, do the finite element contact analysis of the flexible pressurized anchor. Compared the results from the finite element method and the analytic method, and obtained the correct of the two ways.3. Taking use of the method of change a parameter value, fixed the remaining parameters value, modeling a number of finite element modeling, compare and analysis the impact of the main structural parameters of anchor on anchoring performance.4. Imposed different size of the pressure on the adjacent rock from X direction and Y direction, calculate the impact of the different pressure of the adjacent rock for anchoring performance. And calculate when adjacent rock pressure is different, the impact on the adjacent rock under the situation of anchoring the flexible pressurized anchor and non-anchoring the flexible pressurized anchor.5. Applying strength theory, established the strength conditions of steel wire, rubber, and the shear strength condition of steel wire and rubber, and obtained the maximum allowable pull-out load of anchor. And through theoretical calculation and finite element calculation, obtained the impact factor of anchor’s allowable pull-out load.6. Done the ground of pull-out test, shear test and the underground pull-out test of the flexible pressurized anchor, measured the relationship between inner pressure and anchor pulling force and shear properties. Done the seal and bearing stability test, as well as the failure test, summed up the typical failure forms and causes of flexible pressurized anchor.
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