Study On Anchorage Technique Of The Cutting Slope In Disintegrate Rock Mass

The layered disintegrate rock mass is the most popular disintegrated rock massand this kind of rock mass slope's reinforced technology is the most difficult ingeotechnical engineering. As an in-site rock mass reinforced method, anchor has beenused comprehensively after creation and it is taken for the most promising methodthat can reinforce the rock mass directly by the national and overseas engineers. Pointed to the layered disintegrate rock mass cutting-slope's reinforcedtechnology, the corresponding investigation is proceeded in the dissertation. Theinvestigation contents involve slope deformation and failure mechanism, stabilityevaluation method, anchor mechanism, design and compute method, anchor gridbeam slope surface structure etc. The research means include model test, analyticalcomputation, manifold element method, FEM numerical analysis, field engineeringdesign example and field monitoring etc. According above comprehensive andsystemic research, the main results and conclusions of the dissertation are as follows: (1) Model test shows that the failures of the disintegrate rock mass slope includeshallow part failure and deep part failure. whether the slope is anchored or not, awayfrom the slope surface for a certain distance its deformation is continuous and thepresented mechanic characteristic are similar to uniform rock mass slope. So theresemble uniform rock mass slope stability compute method can be used in thedisintegrate rock mass slope's whole stability analysis. (2) The investigation puts forward that it will form three deformation zoneswhich include direct compressed zone , shear deformation zone , continuousdeformation zone when the disintegrate rock mass slope is anchored. The analyticalformula of the direct compressed zone depth induced by the anchor force is putforward for the first time. (3) The view of disintegrate rock mass cutting-slope reinforced by the activeanchor and passive anchor is put forward. And in active anchored slope's deep partfailure circumstances, the active anchor's length is decided by the slope failuresurface obtained by resemble uniform rock mass stability computation; In passiveanchored slope's shallow part failure circumstances, the passive anchor's length isdecided by the direct compressed zone depth. (4) The investigation shows that after being reinforced by the anchors, IIIdisintegrate rock mass cutting-slope's failure surface will shift to deeper zone of theslope and it influences the non-anchored section's length that surpass the slide surfaceof the anchor. The investigation shows that the non-anchored section's length thatsurpasses the slide surface of the anchor can be estimated by Hobst empirical formula. (5) Fracture mechanics investigation of anchored slope shows that applyinganchor force at fracture clip can obtain the best anchor effect and by the decrease ofthe space between anchors, the anchor effect will increase non-linearly. The analyticalformula of the space between anchors is put forward by the fracture mechanicsprinciplely. (6) Slope anchor mechanics is investigated by the numerical manifold elementmethod and ANSYS software. The results show that after anchored, slope rock andsoil's displacement will decrease, stress-distributing grads of the slope-anchored zonewill be evener and the slope will be more stable. (7) The three kinds of strip and block method that used in simplifying anchorforce in the slope stability limited analysis is investigated and put forward for the firsttime. The investigation shows that the value of slope safety coefficient should concernthe compute method, and when a compute method to be used the corresponding safetycoefficient value should be concerned. (8)The investigation shows that the slope anchor beam grid can be analyzed by the theory of cross beam on the elastic foundation.