A method for predicting the stress-strain state of the lining of underground structures, the shape of the cross-section of which is different from the circular outline, is considered. The main task of the study is to develop a methodology for assessing the influence of the parameters of the cross-section shape of underground structures on the stress state of the lining. To solve this problem, a method for calculating the stress state of the lining for arched tunnels with a reverse arch and quasi-rectangular forms is substantiated and developed. The methodology was tested, which showed that the accuracy of the prediction of the stress state of the lining is sufficient to perform practical calculations. An algorithm for multivariate analysis of the influence of the cross-sectional shape of underground structures of arched and quasi-rectangular shapes on the stress state of the lining is proposed. Parametric calculations were performed using the developed algorithm and regularities of the formation of the stress state of the lining of underground structures for various engineering and geological conditions, as well as the initial stress state field, were obtained. A quantitative assessment of the influence of geometric parameters of tunnels on their stress-strain state was performed.
Analysis of anisotropy behavior of clays based on the laboratory testing and publication is presented. Microstructural physical model of interaction between clay aggregates is proposed. Mathematical description of geomaterial based on the microstructural consideration which account for induce and inherent anisotropy is suggested.
In work the option of the multipurpose underground complex being part of the multystoried high-rise building is considered. The complex settles down in underground part of the building and carries out a base role, replacing with itself the usual plates-but-pile base. Predesigns by a method of final elements taking into account staging of construction of an underground complex and the land high-rise building are executed. Sizes and a picture of distribution of vertical displacements are received as a result of calculations.
The main reasons of soil deformation during deep excavation construction are presented. Numerical modeling of deep excavation construction with an account of support system is conducted. Conclusions on the application area of typical soils models is made.
Finite element analysis of tunnel construction in urban area is given. Soil material model parameters determination is considered. 3d finite element analysis of tunnel development is carried out. Variation of settlements and settlement troughs according to face and radial shield pressure and initial stress state are shown. Comparison of numerical modeling results and results of in-situ settlements measurement is done.
Numerical model of lining yield element is created. Induced deformation Force – Displacement behavior of lining yiled elements with different geometrical sections is founded. Deformation state of lining element under induced displacement is presented.
Contact stiffness between two particles is considered. Analysis of interaction between two particles based on the smooth and rough contact is done. Dependence of contact stiffness on normal forces and particles surface roughness is presented.
The intelligent technology of designing of the constructions of pillar underground station is adduced. Station is building with applying of low-settle technology, which takes into consideration main stages of the building process. The scheme of interaction of the system «support lining-soil massif» was accepted as basic scheme of calculations. The calculations of the stress-strain condition of constructions was performed with applying of finite-elements method.
Comparison of results of calculations of the tangential stresses on the inner contour of tunnel lining and radial stresses on the outer contour is done. Stresses are found by solving the problem of interaction in geomechanical system «lining-ground massif» in 2D and 3D model (single layer tunnel lining and double layer tunnel lining). Area of correct application of 2D models are revealed.
Analysis of tunnel induced settlement due to tunnel development with a help of TBM is given in current article. Surface settlement trough and settlement profile in longitudinal and transverse directions is shown below. A brief analysis of semi-empirical method of tunnel induced settlement calculation and determination of strains around excavation is given. Volume loss is given based on the in-situ observation.
This article give a general overview of methods to solve large scale geotechnical problems, nonlinear high deformation and plastic problems, self contact of strata and application of high performance computing.
The article proposes a method for predicting the stress-strain state of the vertical shaft lining in saliferous rocks at the drift landing section. The paper considers the development of geomechanical processes in the saliferous rock in the landing area, the support is viewed as a two-layer medium: the inner layer is concrete, the outer layer is compensation material. With this in view, the paper solves the problem of continuum mechanics in a spatial setting, taking into account the long-term deformation of salts and the compressibility of the compensation layer. Long-term deformation of saliferous rocks is described using the viscoplastic model of salt deformation into the numerical model, and the crushable foam model to simulate the deformation of the compensation layer. This approach considers all stages of the deformation of the compensation layer material and the development of long-term deformations of saliferous rocks, which makes it possible to increase the reliability of the forecast of the stress-strain state of the vertical shaft lining.