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In recent years, pile-anchor structure has been widely used in slope, landslide, pit, dams and other projects, but it lags behind its design theory in engineering applications. This is because the rock mass, pile, prestressed cable between the three forces is a common organism, they are bound to each other with restraint, prestress will change the supporting structure of the soil pressure distribution, thus affecting the support structural forces. Therefore, the supporting structure to solve the problem of pressure on the soil is essential for engineering design, it is safe to play supporting economic structure and function is an important prerequisite. In the pile-anchor structure, since the structure and interaction of rock and soil, soil pressure occurs in the spatial redistribution. Earth pressure redistribution that soil arching effect, this article will call this space three-dimensional soil arching arching slump. Soil arching is inhomogeneous deformation process of evolving forms of load transfer on geotechnical engineering stress and displacement field change and have an important impact on the development process. Soil arching effect and the associated earth pressure calculation problem a long time for the engineering concern, especially in the 20th century, on soil arching of the measured data, the model tests and theoretical research results gradually increased, and began to be applied to practical engineering in, and achieved good results. But it can be seen, so far, on soil arching theory, especially the spatial aspects of soil arching theory is still immature, people's understanding of soil arching effect is not enough depth in the calculation method, there are still some worth exploring, so to carry out research work in this area has become very necessary. Aiming at the soil arching theory research status, the previous studies based on the work of the pile-anchor retaining structure of soil arching effect for a more in-depth study, the main research results achieved include: ⑴ theoretical aspects discussed The pile-anchor structure arching arching mechanism and formation conditions. A comprehensive summary of the basic concepts of soil arching, formation mechanism, classification, there is a condition exists in the form of soil arch arch and soil arching factors; given the destruction of soil arch type; detailed analysis of the horizontal and vertical soil arching soil arching formation mechanism and process; and on the basis of their predecessors, raised questions about the presence of soil arch arch arch form and structure of the foot holding force new insights; further improve the conditions for the existence of soil arching theory, the presence of soil arching generalization the strength condition. ⑵ arching Conditions. Summary analysis of existing domestic and arching calculation method, the proposed new failure mode, a new calculation method of soil arching deduced critical pile spacing, slumping arch arch arch height and three-dimensional collapse within the earth pressure formula. And analysis of rock and soil parameters c,? Value, pile spacing L, B pile width and depth z such right arch height and arch collapse within the earth pressure. ⑶ combining theoretical analysis of soil arching research results, using the finite element analysis software, a detailed study of two-dimensional and three-dimensional Slump Slump arch arch generation mechanism, analyze rock and soil parameters c,? Values, and other factors pile spacing L on soil arching effect. The results from the analysis shows that, with the increase of pile spacing, soil arching regional constantly after the shift, and pile spacing, soil internal friction angle, the greater cohesion, soil arching effect is more obvious.
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