Modeling the stability of horizontal generations worked in parallel to the front of a uniform slope

Abstract

Improvement of modern urban infrastructure, expansion of transport networks, creation of innovative engineering communications – as well as other circumstances stimulate the development of underground construction, both in our country and abroad. Like any underground structure, it should have the ability not to collapse when exposed to external loads. For the successful operation of such structures throughout their entire service life, it is necessary to constantly assess the influence degree of all factors’ totality, one way or another, affect its strength. The task, the purpose of which is to conduct the experimental studies on models made of equivalent materials to assess the geometric parameters’ influence of the “slope – underground working space” system on the stability of the latter, has been set. Geometric parameters mean the shape of the underground working space cross-section and its position in the soil massif: the shape of the underground working space cross-section is round and semi-elliptical; the underground working spaces’ bottom is at the level of the slope bottom, the underground working space position is determined by the shortest distance from the transition point of the bottom to the slope to the vertical axis of the cross-section symmetry. The criterion for long-term stability is a criterion, the qualitative feature of which is the absence of inelastic (plastic) deformation zones on the development contours, and the quantitative indicator is the value of the reduced pressure of connectivity σcon. As a result of model experiments, safe distances d were determined, on which underground working spaces should be located in the near-slope area so that the stability of the “slope - underground working space” system is ensured. It turned out that these distances for underground working spaces of both circular and semi-elliptical cross-section are practically the same, that is, the underground working spaces of such a cross-section, all other sections being equal, were equally stable. Practical coincidence of the model experiments’ results and numerical finite element analysis, calculations, allows us to speak about the experimental data reliability.