Получена зависимость смещения контура выработки от расстояния до забоя, позволяющая рассчитывать ... more Получена зависимость смещения контура выработки от расстояния до забоя, позволяющая рассчитывать нагрузки на крепь с учетом отставания работ по креплению от проходческих работ. Приведены некоторые результаты расчета осевых усилий в элементах крепи. Расчеты выполнены методом конечных элементов в трехмерной постановке. Ключевые слова: крепление, метод конечных элементов, смещения. ROCK DISPLACEMENTS IN THE VICINITY OF THE FACE OF THE UNSUPPORTED EXCAVATION The relationship between displacements of the excavation contour and distance to the excavation face is obtained in the paper. The relationship allows to calculate support pressure with the account for delay of the support installation. Some calculation results of axial forces in the support are given. Calculations are made on the basis of finite-element method with three dimensional models.
The Mining-Geological-Petroleum Engineering Bulletin, 2022
The main question of this paper is the stress-strain state prediction of the vertical shaft's com... more The main question of this paper is the stress-strain state prediction of the vertical shaft's combined lining located at the interface of two layers of dolomite and salt. The study predicts geomechanical processes at the contact of the dolomite layer and the salt layer in the vicinity of the vertical shaft's expanded section, taking into account the operating life of a vertical shaft is equal to 50 years. The results combined lining's stress-strain state, represented as a four-layer medium, where the external layer is concrete, and the three inner layers are used to account for the heterogeneity of cast-iron tubing and are compared with the results received when taking into account the pipe structure. The solution of the problem was carried out in a three-dimensional statement. The calculation of the tubing lining, considering its actual geometry, will increase the accuracy of the forecast of the stress state of the lining, which in turn will favourably affect the justification of its parameters.
Joints often have a significant influence on material characteristics. The discontinuities’ coale... more Joints often have a significant influence on material characteristics. The discontinuities’ coalescence mechanism and complex jointed rock mass structure as a composite need to be further explored. In this study, compression and shear tests were carried out on a jointed rock mass. The purpose of the jointed rock mass behaviour study was to determine the deformation-strength dependencies and to determine the parameters for a quantitative assessment of the joints’ influence on mechanical characteristics. The results show that compression strength depends on the materials’ structure, and there is a detailed description of the joints’ orientation influence on stress-strain dependencies during compression experiments. The numerical method used in this study could be used for the modelling of composite materials and their properties.
The main question of this paper is the stress-strain state prediction of the vertical shaft’s com... more The main question of this paper is the stress-strain state prediction of the vertical shaft’s combined lining located at the interface of two layers of dolomite and salt. The study predicts geomechanical processes at the contact of the dolomite layer and the salt layer in the vicinity of the vertical shaft’s expanded section, taking into account the operating life of a vertical shaft is equal to 50 years. The results combined lining’s stress-strain state, represented as a four – layer medium, where the external layer is concrete, and the three inner layers are used to account for the heterogeneity of cast-iron tubing and are compared with the results received when taking into account the pipe structure. The solution of the problem was carried out in a three-dimensional statement. The calculation of the tubing lining, considering its actual geometry, will increase the accuracy of the forecast of the stress state of the lining, which in turn will favourably affect the justification of...
In this work the strength and deformation characteristics of clay formations in the underground s... more In this work the strength and deformation characteristics of clay formations in the underground space of megacities are investigated. It is found that they have anisotropy of the mechanical characteristics, which are directly connected with the processes of soil formation. The clay layered mass is seen as a transversely isotropic medium, the strength and deformation characteristics of which depend on the direction of load application relative to the plane of bedding. From the experimental results we have obtained indicators of the strength and deformation characteristics which are used as model parameters of a transversely isotropic medium in mathematical and numerical modeling. We have developed geomechanical model of a plastically anisotropic soil mass and estimated the influence of anisotropy on the limiting condition of the soil mass around the tunnel. In order to solve the problem the method of small parameter and finite element method have been used.
The article presents methodical approaches to the computation of the land-surface deformations du... more The article presents methodical approaches to the computation of the land-surface deformations during the construction of underground facilities of complex spatial configuration. Considered methodical approaches are based on numerical methods of analysis. The article presents the computation concept of stress-strain state of rock mass and land-surface deformations during the construction of underground facilities of complex spatial configuration, which is based on the representation of the computational domain in the form of global and local models. The presented concept has been tested in the context of underground facility consisting of three single-bore connected tunnels.
The article is focused on the issues of predicting the earth surface deformation in building unde... more The article is focused on the issues of predicting the earth surface deformation in building underground structures with complex spatial configuration in restrained urban conditions. Attention is mainly paid to the development of a method for predicting deformations of the earth surface caused by building subway stations, based on numerical modeling. The issues of developing numerical models of complex spatial underground structures have been considered, with regard to the construction sequence. A geomechanical model of predicting deformations in construction of underground structures in claystonelike clays, described as a non-linear transversely isotropic medium, has been proposed. Detailed analysis of the results of the monitoring of the earth surface settlement has been made in the construction of the "Obvodny Kanal" subway station in St. Petersburg (Russia). For the construction of the "Obvodny Kanal" subway station, calculation was made in order to determine the deformation of the earth surface. Substantiation of the reliability of the proposed method of predicting deformations of the earth surface is made based on comparing the monitoring results to a numerical simulation.
Proceedings of the Institution of Civil Engineers - Geotechnical Engineering, 2020
Circular tunnels are the most popular shapes used in urban underground transportation system when... more Circular tunnels are the most popular shapes used in urban underground transportation system when mechanized tunneling is used for the tunnel excavation. However, circular tunnels have a small spac...
Получена зависимость смещения контура выработки от расстояния до забоя, позволяющая рассчитывать ... more Получена зависимость смещения контура выработки от расстояния до забоя, позволяющая рассчитывать нагрузки на крепь с учетом отставания работ по креплению от проходческих работ. Приведены некоторые результаты расчета осевых усилий в элементах крепи. Расчеты выполнены методом конечных элементов в трехмерной постановке. Ключевые слова: крепление, метод конечных элементов, смещения. ROCK DISPLACEMENTS IN THE VICINITY OF THE FACE OF THE UNSUPPORTED EXCAVATION The relationship between displacements of the excavation contour and distance to the excavation face is obtained in the paper. The relationship allows to calculate support pressure with the account for delay of the support installation. Some calculation results of axial forces in the support are given. Calculations are made on the basis of finite-element method with three dimensional models.
The Mining-Geological-Petroleum Engineering Bulletin, 2022
The main question of this paper is the stress-strain state prediction of the vertical shaft's com... more The main question of this paper is the stress-strain state prediction of the vertical shaft's combined lining located at the interface of two layers of dolomite and salt. The study predicts geomechanical processes at the contact of the dolomite layer and the salt layer in the vicinity of the vertical shaft's expanded section, taking into account the operating life of a vertical shaft is equal to 50 years. The results combined lining's stress-strain state, represented as a four-layer medium, where the external layer is concrete, and the three inner layers are used to account for the heterogeneity of cast-iron tubing and are compared with the results received when taking into account the pipe structure. The solution of the problem was carried out in a three-dimensional statement. The calculation of the tubing lining, considering its actual geometry, will increase the accuracy of the forecast of the stress state of the lining, which in turn will favourably affect the justification of its parameters.
Joints often have a significant influence on material characteristics. The discontinuities’ coale... more Joints often have a significant influence on material characteristics. The discontinuities’ coalescence mechanism and complex jointed rock mass structure as a composite need to be further explored. In this study, compression and shear tests were carried out on a jointed rock mass. The purpose of the jointed rock mass behaviour study was to determine the deformation-strength dependencies and to determine the parameters for a quantitative assessment of the joints’ influence on mechanical characteristics. The results show that compression strength depends on the materials’ structure, and there is a detailed description of the joints’ orientation influence on stress-strain dependencies during compression experiments. The numerical method used in this study could be used for the modelling of composite materials and their properties.
The main question of this paper is the stress-strain state prediction of the vertical shaft’s com... more The main question of this paper is the stress-strain state prediction of the vertical shaft’s combined lining located at the interface of two layers of dolomite and salt. The study predicts geomechanical processes at the contact of the dolomite layer and the salt layer in the vicinity of the vertical shaft’s expanded section, taking into account the operating life of a vertical shaft is equal to 50 years. The results combined lining’s stress-strain state, represented as a four – layer medium, where the external layer is concrete, and the three inner layers are used to account for the heterogeneity of cast-iron tubing and are compared with the results received when taking into account the pipe structure. The solution of the problem was carried out in a three-dimensional statement. The calculation of the tubing lining, considering its actual geometry, will increase the accuracy of the forecast of the stress state of the lining, which in turn will favourably affect the justification of...
In this work the strength and deformation characteristics of clay formations in the underground s... more In this work the strength and deformation characteristics of clay formations in the underground space of megacities are investigated. It is found that they have anisotropy of the mechanical characteristics, which are directly connected with the processes of soil formation. The clay layered mass is seen as a transversely isotropic medium, the strength and deformation characteristics of which depend on the direction of load application relative to the plane of bedding. From the experimental results we have obtained indicators of the strength and deformation characteristics which are used as model parameters of a transversely isotropic medium in mathematical and numerical modeling. We have developed geomechanical model of a plastically anisotropic soil mass and estimated the influence of anisotropy on the limiting condition of the soil mass around the tunnel. In order to solve the problem the method of small parameter and finite element method have been used.
The article presents methodical approaches to the computation of the land-surface deformations du... more The article presents methodical approaches to the computation of the land-surface deformations during the construction of underground facilities of complex spatial configuration. Considered methodical approaches are based on numerical methods of analysis. The article presents the computation concept of stress-strain state of rock mass and land-surface deformations during the construction of underground facilities of complex spatial configuration, which is based on the representation of the computational domain in the form of global and local models. The presented concept has been tested in the context of underground facility consisting of three single-bore connected tunnels.
The article is focused on the issues of predicting the earth surface deformation in building unde... more The article is focused on the issues of predicting the earth surface deformation in building underground structures with complex spatial configuration in restrained urban conditions. Attention is mainly paid to the development of a method for predicting deformations of the earth surface caused by building subway stations, based on numerical modeling. The issues of developing numerical models of complex spatial underground structures have been considered, with regard to the construction sequence. A geomechanical model of predicting deformations in construction of underground structures in claystonelike clays, described as a non-linear transversely isotropic medium, has been proposed. Detailed analysis of the results of the monitoring of the earth surface settlement has been made in the construction of the "Obvodny Kanal" subway station in St. Petersburg (Russia). For the construction of the "Obvodny Kanal" subway station, calculation was made in order to determine the deformation of the earth surface. Substantiation of the reliability of the proposed method of predicting deformations of the earth surface is made based on comparing the monitoring results to a numerical simulation.
Proceedings of the Institution of Civil Engineers - Geotechnical Engineering, 2020
Circular tunnels are the most popular shapes used in urban underground transportation system when... more Circular tunnels are the most popular shapes used in urban underground transportation system when mechanized tunneling is used for the tunnel excavation. However, circular tunnels have a small spac...
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