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Mechanical responses of underground carriageway structures due to construction of metro tunnels beneath the existing structure:A case study
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作者 Xin Han Fei Ye +3 位作者 Xingbo Han Chao Ren Jing Song Ruliang Zhao 《Deep Underground Science and Engineering》 2024年第2期231-246,共16页
To understand the mechanical response pattern of the existing structure and ground due to the construction of metro tunnels underneath,the finite difference method is adopted to study the torsional deformation and str... To understand the mechanical response pattern of the existing structure and ground due to the construction of metro tunnels underneath,the finite difference method is adopted to study the torsional deformation and stress variation of the existing structure and the effect of underground carriageway structures on the surface subsidence.The curves of the maximum differential subsidence,torsion angle,and distortion of the cross-section of the existing structure show two peaks in succession during traversing of two metro tunnels beneath it.The torsion angle of the existing structure changes when the two tunnels traverse beneath it in opposite directions.The first traversing of the shield tunnel mainly induces the magnitude variation in torsional deformation of the existing structure,but the second traversing of the subsurface tunnel may cause a dynamic change in the magnitude and form of torsional deformation in the existing structure.The shielding effect can reduce the surface subsidence caused by metro tunnel excavation to a certain extent,and the development trend of subsidence becomes slower as the excavation continues. 展开更多
关键词 metro tunnel numerical simulation structural deformation surface subsidence underground carriageway structure
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Numerical analysis on seismic performance of underground structures in liquefiable interlayer sites from centrifuge shaking table test
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作者 Yan Guanyu Xu Chengshun +2 位作者 Zhang Zihong Du Xiuli Wang Xuelai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期781-798,共18页
When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response... When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response of underground structures in liquefiable interlayer sites,and a valid numerical model was obtained through simulation model test.Finally,the calibrated numerical model was used to perform further research on the influence of various distribution characteristics of liquefiable interlayers on the seismic reaction of underground structures.The key findings are as follows.The structure faces the most unfavorable condition once a liquefiable layer is located in the middle of the underground structure.When a liquefiable layer exists in the middle of the structure,the seismic reactions of both the underground structure and model site will increase with the rise of the thickness of the liquefiable interlayer.The inter-story drift of the structure in the non-liquefiable site is much smaller than that in the liquefiable interlayer site.The inter-story drift of the structure is not only associated with the site displacement and the soil-structure stiffness ratio but also closely associated with the slippage of the soil-structure contact interface under the condition of large deformation of the site. 展开更多
关键词 centrifuge shaking table test underground structure liquefiable interlayer sites seismic response validation of numerical model
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Generalized response displacement methods for seismic analysis of underground structures with complex cross section
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作者 Xu Zigang Ding Linling +2 位作者 Du Xiuli Xu Chengshun Zhuang Haiyang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期979-993,共15页
The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing ... The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing geotechnical works(ISO 23469)and code for seismic design of urban rail transit structures(GB 50909-2014).However,there are some obvious limitations in the application of RDM.Springs and the shear stress of the soil could be approximately evaluated for the structures having a simple cross section,such as rectangular and circular structures.It is necessary to propose simplified seismic analysis methods for structures with complex cross sections.This paper refers to the idea of RDM and proposes three generalized response displacement methods(GRDM).In GRDM1,a part of the soil surrounding a structure is selected to generate a generalized underground structure with a rectangular cross section,and the same analysis model as RDM is applied to analyze the responses of the structure.In GRDM2,a hollow soil model without a generalized structure is used to compute the equivalent load caused by the relative displacement of the soil,and the soil-structure interaction model is applied to calculate the responses of the structure.In GRDM3,a continuous soil model is applied to compute the equivalent load caused by the relative displacement and shear stress of the soil,and the soil-structure interaction model is applied to analyze the responses of the structure,which is the same as the model used in GRDM2.The time-history analysis method(THAM)is used to evaluate the accuracy of the proposed simplified methods.Results show that the error of GRDM1 is about 20%,while the error is only 5%for GRDM2 and GRDM3.Among the three proposed methods,GRDM3 has obvious advantages regarding calculation efficiency and accuracy.Therefore,it is recommended to use GRDM3 for the seismic response analysis of underground structures that have conventional simple or complex cross sections. 展开更多
关键词 underground structures seismic analysis response displacement method equivalent seismic load complex cross section
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Rock mass structural recognition from drill monitoring technology in underground mining using discontinuity index and machine learning techniques 被引量:1
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作者 Alberto Fernández JoséA.Sanchidrián +3 位作者 Pablo Segarra Santiago Gómez Enming Li Rafael Navarro 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期555-571,共17页
A procedure to recognize individual discontinuities in rock mass from measurement while drilling(MWD)technology is developed,using the binary pattern of structural rock characteristics obtained from in-hole images for... A procedure to recognize individual discontinuities in rock mass from measurement while drilling(MWD)technology is developed,using the binary pattern of structural rock characteristics obtained from in-hole images for calibration.Data from two underground operations with different drilling technology and different rock mass characteristics are considered,which generalizes the application of the methodology to different sites and ensures the full operational integration of MWD data analysis.Two approaches are followed for site-specific structural model building:a discontinuity index(DI)built from variations in MWD parameters,and a machine learning(ML)classifier as function of the drilling parameters and their variability.The prediction ability of the models is quantitatively assessed as the rate of recognition of discontinuities observed in borehole logs.Differences between the parameters involved in the models for each site,and differences in their weights,highlight the site-dependence of the resulting models.The ML approach offers better performance than the classical DI,with recognition rates in the range 89%to 96%.However,the simpler DI still yields fairly accurate results,with recognition rates 70%to 90%.These results validate the adaptive MWD-based methodology as an engineering solution to predict rock structural condition in underground mining operations. 展开更多
关键词 Drill monitoring technology Rock mass characterization underground mining Similarity metrics of binary vectors structural rock factor Machine learning
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An improved pseudo-static method for seismic resistant design of underground structures 被引量:4
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作者 刘如山 石宏彬 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2006年第2期189-193,共5页
This paper describes a commonly used pseudo-static method in seismic resistant design of the cross section of underground structures. Based on dynamic theory and the vibration characteristics of underground structures... This paper describes a commonly used pseudo-static method in seismic resistant design of the cross section of underground structures. Based on dynamic theory and the vibration characteristics of underground structures, the sources of errors when using this method are analyzed. The traditional seismic motion loading approach is replaced by a method in which a one-dimensional soil layer response stress is differentiated and then converted into seismic live loads. To validate the improved method, a comparison of analytical results is conducted for internal forces under earthquake shaking of a typical shallow embedded box-shaped subway station structure using four methods: the response displacement method, finite element response acceleration method, the finite element dynamic analysis method and the improved pseudo-static calculation method. It is shown that the improved finite element pseudo-static method proposed in this paper provides an effective tool for the seismic design of underground structures. The evaluation yields results close to those obtained by the finite element dynamic analysis method, and shows that the improved finite element pseudo-static method provides a higher degree of precision. 展开更多
关键词 underground structures seismic design finite element method pseudo-static method dynamic analysis method
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Fully fluid-solid coupling dynamic model for seismic response of underground structures in saturated soils 被引量:4
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作者 Li Liang Jiao Hongyun +1 位作者 Du Xiuli Shi Peixin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第2期257-268,共12页
The seismic response characteristics of underground structures in saturated soils are investigated.A fully fluid-solid coupling dynamic model is developed and implemented into ABAQUS with a user-defined element to sim... The seismic response characteristics of underground structures in saturated soils are investigated.A fully fluid-solid coupling dynamic model is developed and implemented into ABAQUS with a user-defined element to simulate the dynamic behavior of saturated soils.The accuracy of the model is validated using a classic example in literature.The performance of the model is verified by its application on simulating the seismic response characteristics of a subway station built in saturated soils.The merits of the model are demonstrated by comparing the difference of the seismic response of an underground structure in saturated soils between using the fully coupling model and a single-phase medium model.The study finds that the fully coupling model developed herein can simulate the dynamic response characteristics of the underground structures in saturated soils with high accuracy.The seismic response of the underground structure tends to be underestimated by using the single-phase medium model compared with using the fully coupling model,which provides a weaker confining action to the underground structure. 展开更多
关键词 underground structure saturated SOIL SEISMIC RESPONSE fluid-solid COUPLING dynamic model user-defined ELEMENT
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DYNAMIC LOAD ANALYSIS OF UNDERGROUND STRUCTURE UNDER EFFECT OF BLAST WAVE 被引量:1
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作者 任云燕 张莉 韩峰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第9期1281-1288,共8页
A semi-analytical method of solving the problem of dynamic stress concentration of arbitrary underground structure under the effect of blast waves was introduced. Using the Fourier transform theory, the shock waves (... A semi-analytical method of solving the problem of dynamic stress concentration of arbitrary underground structure under the effect of blast waves was introduced. Using the Fourier transform theory, the shock waves (in the forms of SH-waves) can be converted into frequency bands. After employing complex functions and conformal mapping, the admittance functions of various underground structures were obtained. Then, the problem of the time domain dynamic stress response of underground structure can be easily solved through the Fourier inverse transform. At last, the results and curves of the dynamic stress for the square, triangle and horseshoe cavity were presented. 展开更多
关键词 dynamic stress blast wave FFT transform underground structure
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Problems of durability and reinforcement measures for underground structures in China 被引量:1
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作者 Xianming Zeng Zhenyu Wang +3 位作者 Junqi Fan Lin Zhao Dalu Lin Jian Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第3期250-259,共10页
In this paper, the bolt- and cable-supported structures mainly refer to anchored cables, anchored bolts, soil nails and other commonly used reinforcing and supporting structures in geotechnical engineering, as well as... In this paper, the bolt- and cable-supported structures mainly refer to anchored cables, anchored bolts, soil nails and other commonly used reinforcing and supporting structures in geotechnical engineering, as well as reinforced soil structures in permanent works. They are often used in combination, or formed into composite bolt-and cable-supported structures, with other traditional construction methods and relevant measures. Distinct characteristics of such structures are that they are most often invisible, exposed to more severe underground corrosive environments and with strict durability requirements. A number of serious durability problems of underground structures are discussed and major achievements and advances in China and abroad in terms of durability and reinforcement measures for underground structures are reviewed, followed by comprehensive analyses. Some suggestions for those problems are put forward. 展开更多
关键词 underground structures DURABILITY service life reinforcement measures
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FUNDAMENTAL OF DYNAMICAL ANALYSIS OF THE BLAST-RESISTANT UNDERGROUND STRUCTURES 被引量:1
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作者 赵玉祥 宋熙太 钱尔旋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第5期407-415,共9页
In this paper, the generalized variational principle of dynamic analysis for the blast-resistant underground structures is established, and the corresponding generalized functional of elastoplastic analysis for underg... In this paper, the generalized variational principle of dynamic analysis for the blast-resistant underground structures is established, and the corresponding generalized functional of elastoplastic analysis for underground structures is derived, and the generalized variational principle of nonconservative system is given, thus the fundamental of dynamical analysis for underground structures to resist blast is proposed. Finally, for the underground cylindrical structure to resist blast, dynamical calculations are made, and compared with the test results. 展开更多
关键词 generalized variational principle dynamical analysis of structure elastoplastic analysis blast-resistant underground structure
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CONSTRUCTION OF UNDERGROUND HYDRAULIC STRUCTURES AND TBM TECHNOLOGY IN CHINA 被引量:3
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作者 FuBingjun GrassoP XuShulin 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2003年第9期1521-1526,共6页
This paper deals with the construction of underground hydraulic structures and TBM technology in China——past,present and future. China ranks number one in the world in water power. But,the ratio of developed to pote... This paper deals with the construction of underground hydraulic structures and TBM technology in China——past,present and future. China ranks number one in the world in water power. But,the ratio of developed to potential hydropower is only about 20%. The exploitable water power in West China,where is featured by high mountain and complex geology,accounts for 83% of the total for China. Most of the project structures have to be located underground. The projected length of hydraulic underground openings per year is about 180 km. Several underground projects completed,under execution and planned are highlighted in this paper. Finally,general information about the development of TBM technology in hydraulic construction in China is outlined. 展开更多
关键词 中国 地下工程 水利水电工程 TBM
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Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions
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作者 Jiaqi Wu Li Zhuo +4 位作者 Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期621-645,共25页
The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling ... The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python codes.The basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web platform.The modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling parameters.The main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric models.In particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling program.Themodularized and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower Station.This complicatedmodel is rapidly generated for the simulation,and the simulation results are reasonable.Thus,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses. 展开更多
关键词 underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling
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Analysis of Interf acial Zone Properties and Permeability of Concrete in Underground Structure
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作者 马保国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第z1期31-34,共4页
Chloride diffusion coefficient and water penetration depth of 3 types concrete were studied. The experimental results show that the concrete permeability decreases itself in the order as follow: pure portland cement c... Chloride diffusion coefficient and water penetration depth of 3 types concrete were studied. The experimental results show that the concrete permeability decreases itself in the order as follow: pure portland cement concrete(CO), concrete added with fly ash(C1), concrete added with both fly ash and silica fume(C2). SEM and microhardness analyses show that the properties of interfacial zone are significantly influenced by silica fume. With the improvement of interfacial zone properties, the permeability especially the Chloride ion diffusivity of concrete significantly decreases. 展开更多
关键词 underground structure water permeability ionic diffusivity Interfacial zone Properties
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Detection of Military Underground Structures through the Remote Sensing Investigation of Phenological Cycle of Crops
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作者 George Melillos Kyriacos Themistocleous +1 位作者 George Papadavid Diofantos G. Hadjimitsis 《Advances in Remote Sensing》 2018年第3期235-244,共10页
This paper aims to explore how field spectroscopy is essential for remote sensing studies for the detection and monitoring of various features such military underground structures in Cyprus. A SVC-HR1024 field spectro... This paper aims to explore how field spectroscopy is essential for remote sensing studies for the detection and monitoring of various features such military underground structures in Cyprus. A SVC-HR1024 field spectroradiometer was used and in-band reflectances were determined for medium resolution Landsat-7 ETM satellite sensor, in order to study possible differences of the spectral signature of vegetation throughout the phenological cycle of plant growth. In this study, two test areas were identified, analyzed and modelled: 1) Military Structure Area (MSA) where underground structure exists, and 2) Reference Area (RA) where underground military structure does not exist. The Normalized Difference Vegetation Index (NDVI) was applied to Landsat-7 ETM and Sentinel-2 satellite images in order to identify the presence or absence of underground structures in the study area. 展开更多
关键词 UAV Field Spectroscopy MILITARY underground structures LANDSAT
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Influence of soil to structure stiffness on the accuracy of the pushover method for underground structures
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作者 Qi Wu Yifeng Zhou Jiawei Jiang 《Earthquake Research Advances》 CSCD 2022年第4期22-27,共6页
The pushover method for underground structures is a seismic analysis method featured by high calculation accuracy and a simple implementation process.The method has been widely used in seismic design and other related... The pushover method for underground structures is a seismic analysis method featured by high calculation accuracy and a simple implementation process.The method has been widely used in seismic design and other related scientific research;however,the influence of different soil-structure flexibility ratios on the accuracy of this method is still not well understood.In this study,we select the cross-section structures beneath the Daikai subway station as the research object and establish 12 finite element analysis models with different soil-structure flexibility ratios using ABAQUS.All models are computed by the dynamic time-history method or the pushover method.Furthermore,the dynamic time-history solution result is taken as the standard solution,and the precision and application of the pushover analysis method are discussed based on the parameters of peak interlayer displacement and peak internal force of the middle column section.The results show that the soil-structure flexibility ratio has a significant influence on the calculation accuracy of the pushover method,and the calculation accuracy of this method is the most ideal when the soil-structure flexibility is equal to 1.The research results can provide significant references for the seismic design of underground structures or the improvement of simplified seismic analysis methods. 展开更多
关键词 underground structure PUSHOVER Soil to structure flexibility ACCURACY
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Preface to the special issue on seismic performance of underground structures: From experiments to analysis
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作者 Su Chen 《Earthquake Research Advances》 CSCD 2022年第4期1-2,共2页
Urban underground structures, especially tunnels, subways, and pipeline systems, are all crucial parts of the infrastructure of modern society. By the end of 2021, China had opened rail transit operations in51 cities ... Urban underground structures, especially tunnels, subways, and pipeline systems, are all crucial parts of the infrastructure of modern society. By the end of 2021, China had opened rail transit operations in51 cities with a total mileage of 8708 km. Considering their importance for life safety and the economy, appropriate seismic design is of prior necessity. 展开更多
关键词 underground SEISMIC structureS
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A comparative analysis of seismic response of shallow buried underground structure under incident P,SV and Rayleigh waves
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作者 Xin Bao Jingbo Liu +2 位作者 Hui Tan Shutao Li Fei Wang 《Earthquake Research Advances》 CSCD 2022年第4期72-78,共7页
In this study,A time-domain seismic response analysis method and a calculation model of the underground structure that can realize the input of seismic P,SV and Rayleigh waves are established,based on the viscoelastic... In this study,A time-domain seismic response analysis method and a calculation model of the underground structure that can realize the input of seismic P,SV and Rayleigh waves are established,based on the viscoelastic artificial boundary elements and the boundary substructure method for seismic wave input.After verifying the calculation accuracy,a comparative study on seismic response of a shallow-buried,double-deck,double-span subway station structure under incident P,SV and Rayleigh waves is conducted.The research results show that there are certain differences in the cross-sectional internal force distribution characteristics of underground structures under different types of seismic waves.The research results show that there are certain differences in the internal force distribution characteristics of underground structures under different types of seismic waves.At the bottom of the side wall,the top and bottom of the center pillar of the underground structure,the section bending moments of the underground structure under the incidences of SV wave and Rayleigh wave are relatively close,and are significantly larger than the calculation result under the incidence of P wave.At the center of the side wall and the top floor of the structure,the peak value of the cross-sectional internal force under the incident Rayleigh wave is larger than the calculation result under SV wave.In addition,the floor of the underground structure under Rayleigh waves vibrates in both the horizontal and vertical directions,and the magnification effect in the vertical direction is more significant.Considering that the current seismic research of underground structures mainly considers the effect of body waves such as the shear waves,sufficient attention should be paid to the incidence of Rayleigh waves in the future seismic design of shallow underground structures. 展开更多
关键词 underground structure Rayleigh wave Artificial boundary Seismic wave input Seismic response
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Seismic performance analysis of underground structures based on random field model of soil mechanical parameters
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作者 Chao Ma Shenghui Zhou Jingwei Chi 《Earthquake Research Advances》 CSCD 2022年第4期3-10,共8页
Soils with spatial variability are the product of natural history.The mechanical properties tested by soil samples from boreholes in the same soil layer may be different.Underground structure service in surrounding so... Soils with spatial variability are the product of natural history.The mechanical properties tested by soil samples from boreholes in the same soil layer may be different.Underground structure service in surrounding soils,their seismic response is controlled by the deformation of the surrounding soils.The variability of soil mechanical parameters was not considered in the current research on the seismic response of underground structures.Therefore,a random field model was established to describe the spatial variability of surrounding soils based on the random field theory.Then the seismic response of underground structures in the random field was simulated based on the time-domain explicit global FEM analysis,and the soil mechanical parameters and earthquake intensity influencing the seismic response of surrounding soils and underground structures were studied.Numerical results presented that,the randomness of soil parameters does not change the plastic deformation mode of surrounding soils significantly.The variation coefficients of inter-story deformation of structures and lateral deformation of columns are much smaller than that of mechanical parameters,and the randomness of soil parameters has no obvious effect on the structural deformation response. 展开更多
关键词 underground structures Random field Seismic performance FEM analysis Variable coefficient
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Numerical investigation on seismic performance of a shallow buried underground structure with isolation devices
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作者 Jianning Wang Guangyu Zhang +2 位作者 Haiyang Zhuang Jing Yang Chen Li 《Earthquake Research Advances》 CSCD 2022年第4期11-21,共11页
A design procedure for improving the seismic performance of unequal-span underground structures by installing isolation devices at the top end of columns is proposed based on the seismic failure mode of frame-type und... A design procedure for improving the seismic performance of unequal-span underground structures by installing isolation devices at the top end of columns is proposed based on the seismic failure mode of frame-type underground structures and the design concept of critical support columns.A two-dimensional finite element model(FEM)for a soil-underground structure with an unequal-span interaction system was established to shed light on the effects of a complex subway station with elastic sliding bearings(ESB)and lead rubber bearings(LRB)on seismic mitigation.It was found that the stiffness and internal force distribution of the underground structure changed remarkably with the installation of isolation devices at the top end of the columns.The constraints of the beam-column joints were significantly weakened,resulting in a decrease in the overall lateral stiffness and an increase in the structural lateral displacement.The introduction of the isolation device effectively reduces the internal force and seismic damage of the frame column;however,the tensile damage to the isolation structure,such as the roof,bottom plate,and sidewall,significantly increased compared to those of the non-isolation structure.Although the relative slip of the ESB remains within a controllable range under strong earthquake excitation as well as frame columns with stable vertical support and self-restoration functions,the LRB shows a better performance during seismic failure and better lateral displacement response of the unequal-span underground structure.The analysis results provide new ideas and references for promoting the application of seismic isolation technology in underground structures. 展开更多
关键词 underground structure Seismic performance Isolation device Elastic sliding bearing Lead rubber bearing Soil-structure interaction
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The Use of Underground Metro Stations and Tunnels as Protective Structures in Case of Nuclear Emergencies
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作者 Mohamed Farahat 《Journal of Environmental Science and Engineering(B)》 2016年第1期35-56,共22页
This paper discusses the use of Underground Metro stations and tunnels as protective structures in case of nuclear emergencies. Six lines are taken as a case study to investigate the use of their underground stations ... This paper discusses the use of Underground Metro stations and tunnels as protective structures in case of nuclear emergencies. Six lines are taken as a case study to investigate the use of their underground stations and tunnels. The research explains the structural design of Underground Metro and the necessary needs for hidden people inside Underground Metro used as shelters. The research investigates the calculations of the number of hidden persons inside Underground Metro used as shelters. A field study has been conducted to an Underground Metro station to detemaine the peaceful use and the emergency use of all basements of the station. Also, the field study aims to determine the existing spaces and the needed spaces of the Underground Metro station to dual--used as a nuclear shelter. Three Underground Metro stations have been selected and a field study has been conducted to determine the usages of these basements, the planning, general and design features for each one of them, and whether they can be used as protective structures for citizens in emergencies. These basements were compared for their protective factors. Also, their capacities for sheltering were calculated. 展开更多
关键词 underground Metro stations and tunnels protective structures nuclear shelters nuclear emergencies.
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Shaking table tests and numerical simulation of dynamic properties of underground structures
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作者 ZHOU Lincong ZHENG Yifeng PAN Shunchun 《Global Geology》 2009年第3期168-173,共6页
It is considered thai the damage of the underground structures caused by earthquakes is minor for a long time. However, the catastrophic damages induced by several recent earthquakes (e. g. Kobe earthquake in 1995 )... It is considered thai the damage of the underground structures caused by earthquakes is minor for a long time. However, the catastrophic damages induced by several recent earthquakes (e. g. Kobe earthquake in 1995 ) revealed that the study on the dynamic properties of the underground structures is indispensable. The dynamic behavior and damage mechanism of underground structure are analyzed by using shaking table tests ( both shallow-and deep-buried) and numerical simulation (3D FEM) including horizontal and vertical input motions, individually and simultaneously. From the results, the underground structure collapsed due to strong horizontal forces although vertical deformation is not negligible. The vertical excitation increases the response of structure, especially the stress and shear stress at the upper section; the soil influenced the property of soilstructure system. In the same excitation, the response in shallow-buried test is larger than deep case. Both overburden and vertical earthquake play important roles in the response of structure and those are two critical aspects in the design of the large-span underground structures, such as subway stations. 展开更多
关键词 underground structures EARTHQUAKE shaking table test SIMULATION
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