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Sustainability in Geology and Civil Engineering

A special issue of Sustainability (ISSN 2071-1050). This special issue belongs to the section "Green Building".

Deadline for manuscript submissions: closed (1 October 2023) | Viewed by 37240

Special Issue Editors

Dr. Danqing Song

E-Mail Website
Guest Editor
1. School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China
2. State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China
Interests: disaster-causing mechanism, prevention and control technology of underground engineering under hydro-dynamic coupling
Special Issues, Collections and Topics in MDPI journals
Dr. Zhuo Chen

E-Mail Website
Guest Editor
College of Civil Engineering, Sichuan Agricultural University, Chengdu, China
Interests: landslides; rock avalanches; debris flows; debris floods
Special Issues, Collections and Topics in MDPI journals
Dr. Mengxin Liu

E-Mail Website
Guest Editor
Institute of Cold Regions Science and Engineering, School of Civil Engineering, Northeast China Observatory and Research Station of Permafrost Geo-Environment of the Ministry of Education, Northeast Forestry University, Harbin, China
Interests: engineered cementitious composites; aging mechanism of materials; micromechanics; green high performance concrete
Dr. Yutian Ke

E-Mail Website
Guest Editor
GEOPS, Université Paris-Saclay-CNRS, Orsay, France
Interests: landscape evolution and carbon cycle

Special Issue Information

Dear Colleagues,

In 2014, a plan entitled “Transforming Our World: The 2030 Agenda for Sustainable Development (Agenda 2030)” was proposed by the United Nations (UN) at the UN Sustainable Development Summit to fix global problems. It states 17 Sustainable Development Goals (SDGs or Global Goals) to overcome the world’s challenges, including industry, innovation, infrastructure, and the effects of climate change. Civil engineering makes a great contribution to the development of human civilization, but also consumes a large number of resources and energy. Sustainable civil engineering is one of the important ways to realize the sustainable development of human society. Under the influence of global environmental change and human activities, civil engineering construction and operation are faced with more and more disasters, and sustainable development has become the primary concern of civil engineering. Disaster prevention and mitigation of infrastructure engineering has become one of the important research fields in civil engineering. In recent years, resilience civil engineering design has gradually become the international research frontier in this field. The main goal of "resilience design" is to improve the capability of civil engineering to deal with risks, and to comprehensively improve the robustness, adaptability and post-disaster recovery of the functional system of engineering structure and geological body. In addition, the goal of "green development, energy saving and emission reduction, low-carbon economy" has gradually become one of the inevitable requirements for the sustainable development of civil engineering construction industry.

Many efforts have been made on the sustainability of civil engineering and various analytical methods and theories have been developed. However, the sustainable development of civil engineering is a systematic theory and technology system in many aspects of design, and the related construction technology, evaluation technology, prevention and control technology, repair technology, design theory and other aspects are not completely clear. Methods of investigation, experiment and numerical analysis also need to be developed.

This Special Issue aims to provide an outlet for original research and review articles focusing on the most recent advances and challenges related to sustainable development in geotechnical and structural engineering. We welcome submissions related to field investigations and monitoring, theoretical derivations, laboratory tests, numerical and physical modeling.

In this Special Issue, original research articles and reviews are welcome.

Research areas may include (but are not limited to) the following:

  • Sustainable design method and theory in geotechnical engineering and structural engineering
  • Design, construction, operation and maintenance technology for green civil engineering
  • New environmentally friendly, economical and recyclable building materials
  • Advanced methods for monitoring disaster process in geotechnical engineering and structural engineering
  • Application or case study of the numerical method and physical simulation method in geotechnical and structural engineering disasters
  • Progress of analysis and simulation techniques for geotechnical and structural disasters
  • Engineering structure and geophysical characteristics under multi-load coupling
  • Disaster risk assessment and mitigation measures of engineering structure and geotechnical engineering at different scales
  • Other hazards (e.g., deterioration of engineering structure or rock-soil body subject to frequent earthquake, heavy rainfall, freeze–thaw, etc.) assessment, prevention and control technology.

We look forward to receiving your contributions.

Dr. Danqing Song
Dr. Zhuo Chen
Dr. Mengxin Liu
Dr. Yutian Ke
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sustainability is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • sustainability
  • geotechnical engineering
  • structural engineering
  • disaster evaluation
  • disaster prevention and control
  • green building materials
  • numerical analysis
  • model test

Published Papers (23 papers)

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Research

16 pages, 4688 KiB  
Article
Study on Surrounding Rock Failure Law of Gob-Side Entry Based on the Second Invariant of Deviatoric Stress
by Xiaozhou Liu, Hu Xu, Ben Li, Wenrui He, Xian Liang and Hongchun Xia
Sustainability 2023, 15(13), 10569; https://doi.org/10.3390/su151310569 - 05 Jul 2023
Cited by 1 | Viewed by 586
Abstract
The second invariant of deviatoric stress of the coal and rock mass is closely related to the distortion energy driving the deformation and failure of the surrounding rock. Based on the second invariant of deviatoric stress, this study built a global model of [...] Read more.
The second invariant of deviatoric stress of the coal and rock mass is closely related to the distortion energy driving the deformation and failure of the surrounding rock. Based on the second invariant of deviatoric stress, this study built a global model of gob-side entry with different widths of the coal pillar through numerical analysis, and compared and analyzed the evolution law of the surrounding rock distortion energy, plastic location state, and roadway deformation with the width of the coal pillar. This study concluded that the peak distortion energy in the virgin coal rib and the roof and floor of the gob-side entry gradually increases with the reduction in the coal pillar width. When the coal pillar width is 5 m, the second invariant peak value of deviatoric stress in the virgin coal rib reaches the maximum of 294.8 MPa2. When the width of the coal pillar is reduced from 30 m to 5 m, the second invariant of the deviatoric stress in the side of the coal pillar and the roof and floor of the side presents the law of first increasing and then decreasing. The greater the damage degree of the coal pillar, the smaller the distortion energy it contains. The distortion energy is the key factor in driving the deformation and failure of the surrounding rock. The greater the distortion energy, the greater the deformation degree of the surrounding rock, the more vulnerable it is to external mining stress disturbance, and the greater the difficulty in controlling the stability of the roadway-surrounding rock. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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21 pages, 2882 KiB  
Article
A General Framework for the Impact of Shield Tunnel Construction on Existing Tunnel in Soil
by Pingrang Wang, Junhao Wu, Danqing Song and Mingfei Zhang
Sustainability 2023, 15(12), 9226; https://doi.org/10.3390/su15129226 - 07 Jun 2023
Viewed by 1006
Abstract
During the excavation process of shield tunneling, it is inevitable that the surrounding soil mass is disturbed, which will affect the adjacent structures. This paper proposes a general framework for the impact of shield tunneling construction on existing tunnels. First, the impact partition [...] Read more.
During the excavation process of shield tunneling, it is inevitable that the surrounding soil mass is disturbed, which will affect the adjacent structures. This paper proposes a general framework for the impact of shield tunneling construction on existing tunnels. First, the impact partition of shield tunneling construction regarding adjacent tunnels and buildings is established by a three-dimensional numerical analysis method. Then, the displacement of adjacent tunnels and buildings is predicted using fuzzy gray theory. Finally, based on the results of a numerical simulation and experiment, the risk classification standard of adjacent buildings is established. This framework has certain reference significance and value for the deformation prediction and safety evaluation of adjacent buildings. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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24 pages, 11971 KiB  
Article
Cyclic Bond-Slip Behavior of Partially Debonded Tendons for Sustainable Design of Non-Emulative Precast Segmental Bridge Columns
by Leilei Xia, Hongcheng Hu, Shiyu Guan, Yasir Ibrahim Shah and Yingqi Liu
Sustainability 2023, 15(10), 8128; https://doi.org/10.3390/su15108128 - 17 May 2023
Viewed by 1053
Abstract
The precast segmental bridge columns incorporating resettable sliding joints have been proposed to extend the accelerated bridge construction techniques to regions of moderate to high seismicity while fulfilling the sustainability-based resilient seismic design concept. Following a rethink of the design strategy in the [...] Read more.
The precast segmental bridge columns incorporating resettable sliding joints have been proposed to extend the accelerated bridge construction techniques to regions of moderate to high seismicity while fulfilling the sustainability-based resilient seismic design concept. Following a rethink of the design strategy in the light of inspirations from hybrid sliding-rocking joints, the design of resettable sliding joints can accommodate a certain amount of horizontal sliding displacement and adopt partially debonded tendons in a vertical manner, probably resulting in complicated tensile-flexural loading scenarios in these tendons during earthquakes, which is rarely considered in practice. In this paper, the sustainable design of resettable sliding joints is introduced. A tailor-made setup was established and simplified cyclic bond-slip tests were conducted to validate the practicality of the proposed partially debonded tendon system. Twelve specimens were fabricated using different strands and grouting techniques, and a two-stage numerical model was proposed to interpret the experimental results of seven typical specimens. The results suggest that the deterioration of reloading stiffnesses can be captured by an additional effective length caused by bond failure, and the strands perform mostly elastically under relatively large transverse displacements. The loading stiffness of the anchorage is 26.3 kN/mm, and it has significant effects and the proposed two-stage model can satisfactorily capture the envelope of the response of the partially debonded tendons, providing practical design for the proposed partially debonded tendons used in sustainable non-emulative precast segmental bridge columns. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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17 pages, 7884 KiB  
Article
Support Control Design of Mining Roadway under Goaf of Close-Distance Coal Seam
by Guozhi Lu and Ping Ni
Sustainability 2023, 15(6), 5420; https://doi.org/10.3390/su15065420 - 18 Mar 2023
Cited by 1 | Viewed by 1186
Abstract
Coal resources have always been the focus of attention in the field of sustainable development. Based on the problem of surrounding rock control in close-distance coal seams, first, a mechanical model of floor failure was established based on the 29204 working face in [...] Read more.
Coal resources have always been the focus of attention in the field of sustainable development. Based on the problem of surrounding rock control in close-distance coal seams, first, a mechanical model of floor failure was established based on the 29204 working face in Dongqu Mine; the failure mechanism of the floor was revealed by the zero displacement line, and a method to judge the occurrence state of the roof in the lower coal seam was put forward. Furthermore, by FLAC3D numerical simulation software, the mechanical model is verified, and the optimal support parameters are optimized, and the optimal water–cement ratio and grouting pressure are determined to be 0.6 and 3 MPa respectively. The application shows that the roof displacement is reduced by about 73.48% compared with the control group. Compared with the control group, the cable stress decreased by about 50.68%, and the application effect is remarkable. The research results provide an effective solution to ensure the sustainable development of coal resources and disaster prevention. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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17 pages, 6816 KiB  
Article
Seismic Dynamic Response and Lining Damage Analysis of Curved Tunnel under Shallowly Buried Rock Strata
by Shijie Bu, Xiaojiu Feng, Luyan Yao, Fujian Yang, Yongtian Xie and Shaofeng Liu
Sustainability 2023, 15(6), 4905; https://doi.org/10.3390/su15064905 - 09 Mar 2023
Cited by 1 | Viewed by 1073
Abstract
It is still challenging to anticipate with accuracy how tunnels will behave and if they will fail when subjected to an earthquake load. In this study, assuming nonlinear material behavior and a three-dimensional inelastic rock medium, the theory of damage mechanics is applied [...] Read more.
It is still challenging to anticipate with accuracy how tunnels will behave and if they will fail when subjected to an earthquake load. In this study, assuming nonlinear material behavior and a three-dimensional inelastic rock medium, the theory of damage mechanics is applied to numerical simulation to build a curved tunnel-surrounding rock model, whose correctness was verified in laboratory experiments. To better understand the influence of surrounding rock strength on the seismic performance of a curved tunnel, the stratum parameters of the curved tunnel-surrounding rock system are quantified. The findings demonstrate that the damage process in curved tunnels is a circular process of damage change, and the model accurately captures these structural aspects of the damage evolution process. In addition, structural damage can be identified using displacement detection because the displacement of a curved tunnel is directly related to its compression damage. Finally, the seismic response of the curved tunnel-surrounding rock system is studied parametrically to determine the extent to which different parameters affect the seismic response. These parameters, including elastic modulus, friction angle, cohesion, and Poisson’s ratio, are characteristics of rock-medium materials. We then created multi-factor evaluation formulas to direct the surrounding rock to reinforce. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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15 pages, 8452 KiB  
Article
A Comprehensive In Situ Investigation on the Reinforcement of High-Filled Red Soil Using the Dynamic Compaction Method
by Lei Wang, Fenglei Du, Yonghui Liang, Wensheng Gao, Guangzhe Zhang, Zhiqiang Sheng and Xiangsheng Chen
Sustainability 2023, 15(6), 4756; https://doi.org/10.3390/su15064756 - 07 Mar 2023
Cited by 1 | Viewed by 1302
Abstract
High-filled red soil typically lacks sufficient bearing capacity, which can pose significant challenges when constructing building foundations. One economical and effective method for the reinforcement of high-filled red soil is the dynamic compaction (DC) method. However, the design parameters for reinforcing high-filled red [...] Read more.
High-filled red soil typically lacks sufficient bearing capacity, which can pose significant challenges when constructing building foundations. One economical and effective method for the reinforcement of high-filled red soil is the dynamic compaction (DC) method. However, the design parameters for reinforcing high-filled red soil using the DC method are largely based on experience, which indicates the significant value of field results of related engineering practice. In this paper, we report a field study that was carried out to investigate the effect of impact energy on the treatment of super-high-filled ground with red soil in southwestern Yunnan, China, where three pilot DC tests were designed and conducted with three different impact energies (4000 kN·m, 8000 kN·m and 15,000 kN·m). To evaluate the reinforcement effect and optimize the DC operational parameters, a series of in situ tests, including settlement monitoring, standard penetration tests, dynamic penetration tests, surface wave velocity tests and plate-load tests, were carried out. Furthermore, the improvement depth of DC was discussed. The results of the field study show that the characteristic value of the ground bearing capacity of the three test zones could reach 250 kPa, which coincides with the design requirement, although the improvement depth of testing zone III fails to reach the required depth. This study helps to improve the in situ recycling of high-filled soil, thereby promoting the sustainable development of engineering construction. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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24 pages, 8787 KiB  
Article
Numerical Investigation of a Local Precise Reinforcement Method for Dynamic Stability of Rock Slope under Earthquakes Using Continuum–Discontinuum Element Method
by Danqing Song, Wanpeng Shi, Chengwen Wang, Lihu Dong, Xin He, Enge Wu, Jianjun Zhao and Runhu Lu
Sustainability 2023, 15(3), 2490; https://doi.org/10.3390/su15032490 - 30 Jan 2023
Cited by 4 | Viewed by 1201
Abstract
The slope reinforcement scheme has an important influence on the prevention and control of landslides. A reasonable reinforcement scheme can improve the reliability, economy and efficiency of landslide resistance. It is urgent to establish a local precise reinforcement method for landslides on the [...] Read more.
The slope reinforcement scheme has an important influence on the prevention and control of landslides. A reasonable reinforcement scheme can improve the reliability, economy and efficiency of landslide resistance. It is urgent to establish a local precise reinforcement method for landslides on the basis of clear process and the instability modes of landslides. Taking a high-steep anti-dip rock slope as an example, six numerical models are established by using the continuum–discontinuum element method (CDEM) to carry out seismic damage and dynamic analysis of slopes. By comparing the seismic response and damage characteristics of being unstrengthened, local precise reinforcement and overall reinforcement models, the applicability of the proposed local precise reinforcement method for the slopes is discussed. The results show that the determination of the dynamic amplifying effect and seismic damage characteristics of slopes is the primary prerequisite of the local precise reinforcement method. The dynamic amplification effect of the slope toe, crest and shallow slope surface are much larger, that is, they are the potential reinforcement areas. The local precision reinforcement times should be controlled within a certain number of times, and the slope after the first three times of the local reinforcement effect is the best. However, more than three times after the reinforcement effect it becomes worse. Moreover, the dynamic amplification effect, the equivalent crack ratio and the mechanical energy of the slope after three times of local precision reinforcement are similar to the overall reinforcement effect, which indicates that local precision reinforcement has good feasibility. This work can provide references for landslide disasters prevention and control. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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14 pages, 1852 KiB  
Article
Response Analysis of Curved Tunnel under Near-Field Long-Period Ground Motion Considering Seismic Wave Propagation Effect
by Shaofeng Liu, Luyan Yao, Xiaojiu Feng and Peng Wang
Sustainability 2023, 15(1), 60; https://doi.org/10.3390/su15010060 - 21 Dec 2022
Cited by 2 | Viewed by 1202
Abstract
In this paper, long-period ground motion is used as the dynamic input to study the performance evolution of curved tunnel lining structure under seismic wave propagation excitation. This paper presents numerical studies on seismic waves, considering propagation effect, and aims to illustrate the [...] Read more.
In this paper, long-period ground motion is used as the dynamic input to study the performance evolution of curved tunnel lining structure under seismic wave propagation excitation. This paper presents numerical studies on seismic waves, considering propagation effect, and aims to illustrate the response principle and structural failure mechanism of tunnel structures under long-period ground motion. Firstly, based on the dynamic analysis method, the dynamic balance equation of a tunnel under the seismic wave effect was analyzed. Secondly, this equation was applied to the 3D finite element software, the corresponding numerical model and boundary conditions were established, and the parameterized numerical analysis of the tunnel was carried out. Finally, according to the numerical simulation results, the seismic response principle and structural failure mechanism of a tunnel structure under long-period ground motion were discussed. The research results show that the depth and segment thickness of the tunnel significantly affect the seismic performance of the tunnel. The seismic response mechanism of a curved tunnel is complex, which shows that the relative displacements on the left and right symmetrical positions are different. The displacement inside the curve is less than the displacement outside the curve. Compared with other types of ground motion, the near-site motion considering the seismic wave propagation effect can lead to large deformation of the tunnel, which damages the lining structure greatly, and the enhancement effect is prominent for the long shield tunnel. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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22 pages, 16372 KiB  
Article
Investigation on the Seismic Wave Propagation Characteristics Excited by Explosion Source in High-Steep Rock Slope Site Using Discrete Element Method
by Danqing Song, Xuerui Quan, Mengxin Liu, Chun Liu, Weihua Liu, Xiaoyu Wang and Dechao Han
Sustainability 2022, 14(24), 17028; https://doi.org/10.3390/su142417028 - 19 Dec 2022
Cited by 5 | Viewed by 2116
Abstract
The influence of seismic waves induced by explosion sources on the dynamic response characteristics of rock slope sites is one of the most important problems affecting engineering construction. To investigate the wave propagation characteristics and attenuation law of seismic waves induced by explosive [...] Read more.
The influence of seismic waves induced by explosion sources on the dynamic response characteristics of rock slope sites is one of the most important problems affecting engineering construction. To investigate the wave propagation characteristics and attenuation law of seismic waves induced by explosive sources in rock sites from the perspective of time and frequency domains, the high-performance matrix discrete element method (MatDEM) is used to carry out numerical simulation tests on a granite rock medium site. The discrete element model of the high-steep rock slope is established by MatDEM, and the dynamic analysis of the rock medium site is conducted by loading blasting vibration load to generate seismic waves. The results show that the seismic waves in the rock site present characteristics of arc propagation attenuation. The maximum attenuation rate of the dynamic response is the fastest within 0.3 s and 25 m from the explosion source. The slope region can weaken the dynamic response of seismic waves generated by the explosion source. In particular, the high-frequency band (>20 Hz) has an obvious filtering effect. The dynamic response of the P-wave induced by the explosive source is greater than that of the S-wave in the bedrock and surface region. The dynamic amplification effect of the P-wave is greater than that of the S-wave in the slope region. The seismic waves in the slope region show an attenuation effect along the slope surface and have a typical elevation amplification effect inside the slope. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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21 pages, 9269 KiB  
Article
Application of Long-Range Cross-Hole Acoustic Wave Detection Technology in Geotechnical Engineering Detection: Case Studies of Tunnel-Surrounding Rock, Foundation and Subgrade
by Lihu Dong, Jundong Chen, Danqing Song, Chengwen Wang, Xiaoli Liu, Mengxin Liu and Enzhi Wang
Sustainability 2022, 14(24), 16947; https://doi.org/10.3390/su142416947 - 17 Dec 2022
Cited by 4 | Viewed by 1420
Abstract
The adverse geological conditions of soil cave, karst cave and goaf in deep foundation directly affect the safety and economy of geotechnical engineering construction. It is a difficult problem in geotechnical engineering detection to detect the distribution of bad geological conditions efficiently and [...] Read more.
The adverse geological conditions of soil cave, karst cave and goaf in deep foundation directly affect the safety and economy of geotechnical engineering construction. It is a difficult problem in geotechnical engineering detection to detect the distribution of bad geological conditions efficiently and accurately. Aiming at the problems of short penetrating distance and low resolution of cross-hole acoustic wave detection in rock-soil mass, based on the characteristics of acoustic wave propagation in rock and soil layers and comprehensively utilizing the spark source and data acquisition device, a long-distance cross-hole acoustic wave detection technology is proposed. According to the indoor concrete model test and field tests of geotechnical engineering, the applicability of the long-distance cross-hole acoustic wave detection technology in the detection of geotechnical structure and adverse geological phenomena under complex geological conditions is verified. The results show that acoustic wave CT imaging can accurately detect the cavities in the indoor concrete model test. In addition, the field tests of the grouting effect of tunnel-surrounding rock, high-rise building foundation and subgrade further verify the rapidity, accuracy and intuitiveness of the long-distance cross-hole acoustic wave detection technology. This work provides a reference for eliminating the potential safety problems caused by adverse geological conditions and similar geotechnical engineering investigation. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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17 pages, 2923 KiB  
Article
Experimental Investigation and Micromechanical Modeling of Hard Rock in Protective Seam Considering Damage–Friction Coupling Effect
by Chuangye Zhang, Wenyong Liu, Chong Shi, Shaobin Hu and Jin Zhang
Sustainability 2022, 14(23), 16296; https://doi.org/10.3390/su142316296 - 06 Dec 2022
Viewed by 1074
Abstract
The hard rock in the protective coal seam of the Pingdingshan Mine in China is a typical quasi-brittle material exhibiting complex mechanical characteristics. According to available research on the mechanical property, the inelastic deformation and development of damage are considered related with crack [...] Read more.
The hard rock in the protective coal seam of the Pingdingshan Mine in China is a typical quasi-brittle material exhibiting complex mechanical characteristics. According to available research on the mechanical property, the inelastic deformation and development of damage are considered related with crack initiation and propagation, which are main causes of the material degradation. In the present study, an original experimental investigation on the rock sample of the Pingdingshan coal mine is firstly carried out to obtain the basic mechanical responses in a conventional triaxial compression test. Based on the homogenization method and thermodynamic theory, a damage–friction coupled model is proposed to simulate the non-linear mechanical behavior. In the framework of micromechanics, the hard rock in a protective coal seam is viewed as a heterogeneous material composed of a homogeneous solid matrix and a large number of randomly distributed microcracks, leading to a Representative Elementary Volume (REV), i.e., the matrix–cracks system. By the use of the Mori–Tanaka homogenization scheme, the effective elastic properties of cracked material are obtained within the framework of micromechanics. The expression of free energy on the characteristic unitary is derived by homogenization methods and the pairwise thermodynamic forces associated with the inelastic strain and damage variables. The local stress tensor is decomposed to hydrostatic and deviatoric parts, and the effective tangent stiffness tensor is derived by considering both the plastic yield law and a specific damage criterion. The associated generalized Coulomb friction criterion and damage criterion are introduced to describe the evolution of inelastic strain and damage, respectively. Prepeak and postpeak triaxial response analysis is carried out by coupled damage–friction analysis to obtain analytical expressions for rock strength and to clarify the basic characteristics of the damage resistance function. Finally, by the use of the returning mapping procedure, the proposed damage–friction constitutive model is applied to simulate the deformation of Pingdingshan hard rock in triaxial compression with respect to different confining pressures. It is observed that the numerical results are in good agreement with the experimental data, which can verify the accuracy and show the obvious advantages of the micromechanic-based model. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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17 pages, 4234 KiB  
Article
Modified RMR Rock Mass Classification System for Preliminary Selection of Potential Sites of High-Level Radioactive Waste Disposal Engineering
by Yue Tong, Yao Yue, Zhongkai Huang, Liping Zhu, Zhihou Li and Wei Zhang
Sustainability 2022, 14(23), 15596; https://doi.org/10.3390/su142315596 - 23 Nov 2022
Viewed by 1456
Abstract
This paper proposed a modified Rock Mass Rating (RMR) system, the RMRHLW system, for evaluating the rock quality of High-level Radioactive Waste (HLW) geological disposal engineering. Some salient factors, including the weakening of groundwater and temperature on the uniaxial compressive [...] Read more.
This paper proposed a modified Rock Mass Rating (RMR) system, the RMRHLW system, for evaluating the rock quality of High-level Radioactive Waste (HLW) geological disposal engineering. Some salient factors, including the weakening of groundwater and temperature on the uniaxial compressive strength, the continuity of index values, the geostress, the rock permeability, and the groundwater chemical properties, were further incorporated based on the widely used RMR system. The proposed RMRHLW system was then verified by the case study of selection of nine candidate sites for HLW disposal engineering in China. The results indicated that the rock quality of the Xinchang site was the best and ranked as the most appropriate site, while the Jiujing site ranked the worst. Compared with the traditional RMR system, the proposed RMRHLW system can further consider crucial factors related to the long-term safety of HLW disposal and better reflect the differences between the potential sites. It can facilitate engineers to preliminarily evaluate the rock quality of the potential sites for High-level Radioactive Waste geological disposal engineering. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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18 pages, 10905 KiB  
Article
Variations in Permeability and Mechanical Properties of Basaltic Rocks Induced by Carbon Mineralization
by Zhenni Ye, Xiaoli Liu, Huan Sun, Qinxi Dong, Weisheng Du and Qijian Long
Sustainability 2022, 14(22), 15195; https://doi.org/10.3390/su142215195 - 16 Nov 2022
Cited by 4 | Viewed by 2313
Abstract
Carbon capture, utilization, and storage (CCUS/CCS) is a strategic choice for ensuring energy security and reducing carbon dioxide emissions across the globe. The injection of CO2 into the basaltic reservoir is one strategy for the permanent disposal of carbon emissions. Basaltic rocks, [...] Read more.
Carbon capture, utilization, and storage (CCUS/CCS) is a strategic choice for ensuring energy security and reducing carbon dioxide emissions across the globe. The injection of CO2 into the basaltic reservoir is one strategy for the permanent disposal of carbon emissions. Basaltic rocks, which are widely distributed in Hainan Island, are capable of CO2 geological sequestration. In this study, the reaction of CO2-NaOH/Ca(OH)2-basaltic rocks under conditions of 6.0 M Pa and 30 °C was performed using basaltic samples collected from the Fushan area of the Hainan Province to evaluate the sequestration of CO2 in basalt by mineralization. Then, the effect of CO2 mineralization on the permeability and mechanical properties of basaltic rocks was evaluated using X-ray computer tomography and triaxial compression testing at 21.0 MPa. In addition, microwave technology was used to irradiate the basaltic rocks before mineralization. Changes in the permeability of basalt before and after mineralization and microwave irradiation were simulated numerically, and their effects on the mechanical strength deterioration of basalt were analyzed according to the rock mechanics using triaxial testing. Based on these results, a new method for the induction of basalt deterioration, mineralization, CO2 injectivity, and storage capacity using microwave irradiation is proposed for use in CCUS/CCS engineering. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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17 pages, 4946 KiB  
Article
Study on Influence of Confining Pressure on Strength Characteristics of Pressurised Frozen Sand
by Fangnian Song and Weihao Yang
Sustainability 2022, 14(21), 14467; https://doi.org/10.3390/su142114467 - 03 Nov 2022
Viewed by 1281
Abstract
In order to reveal the influence law of freezing pressure and confining pressure on the strength characteristics of frozen sand, with the self-developed high-pressure frozen soil triaxial instrument, the triaxial compression tests of frozen sand under different freezing pressures and confining pressures were [...] Read more.
In order to reveal the influence law of freezing pressure and confining pressure on the strength characteristics of frozen sand, with the self-developed high-pressure frozen soil triaxial instrument, the triaxial compression tests of frozen sand under different freezing pressures and confining pressures were carried out. The test results show that the freezing pressure will not change the stress–strain curve of the frozen sand. Similar to the confining pressure, the freezing pressure influences the strength of the frozen soil in two ways: strengthening and weakening. The threshold confining pressure resulting from the test was about 45 MPa. Through comparison of the initial elastic modulus with the secant elastic modulus at 0.5 times the strength, it is found that the initial elastic modulus is more appropriate to use in engineering calculations. The internal friction angle is greatly affected by the freezing pressure, and cohesion shows little change with the freezing pressure. Compared with the test results and other constitutive equations, it is found that the constitutive equation established in this paper considering the effect of freezing pressure can better describe the stress–strain relationship of the pressurised frozen sand. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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13 pages, 6506 KiB  
Article
Spacing Optimization of the TBM Disc Cutter Rock Fragmentation, Based on the Energy Entropy Method
by Chen Xu, Yujie Zhu, Danqing Song, Xiaoli Liu, Wanli Guo and Enzhi Wang
Sustainability 2022, 14(20), 13226; https://doi.org/10.3390/su142013226 - 14 Oct 2022
Cited by 2 | Viewed by 1271
Abstract
We used the hyperbolic Drucker–Prager and damage-failure models to simulate a three-dimensional rock fragmentation with a tunnel boring machine (TBM) disc cutter through ABAQUS. The energy entropy method was proposed to identify the optimal disc cutter spacing. In order to verify the results [...] Read more.
We used the hyperbolic Drucker–Prager and damage-failure models to simulate a three-dimensional rock fragmentation with a tunnel boring machine (TBM) disc cutter through ABAQUS. The energy entropy method was proposed to identify the optimal disc cutter spacing. In order to verify the results of the numerical simulation, previous linear cutting machine (LCM) test data were referred to. The results of the numerical simulation were verified by comparing the mean rolling force and the specific energy against the corresponding values from the LCM tests. The proposed energy entropy method showed a good agreement with the LCM test results, thus proving its usefulness in analyzing rock fragmentation for various disc cutter spacings. The comparison between energy entropy and the specific energy showed that both methods provide similar conclusions with regard to optimal spacing. The results of this research showed that energy entropy can predict the performance of TBM disc cutters and could help improve their design. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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16 pages, 4135 KiB  
Article
Computer-Aided Slope Stability Analysis of a Landslide—A Case Study of Jhika Gali Landslide in Pakistan
by Muhammad Nasir Amin, Muhammad Umair Ashfaq, Hassan Mujtaba, Saqib Ehsan, Kaffayatullah Khan and Muhammad Iftikhar Faraz
Sustainability 2022, 14(20), 12954; https://doi.org/10.3390/su142012954 - 11 Oct 2022
Cited by 3 | Viewed by 2405
Abstract
The present research study has been undertaken to carry out slope stability evaluation of the Jhika Gali landslide in Pakistan using GeoStudio. For this purpose, the site geometry of the existing slope adjacent to the slided one was measured and samples were collected [...] Read more.
The present research study has been undertaken to carry out slope stability evaluation of the Jhika Gali landslide in Pakistan using GeoStudio. For this purpose, the site geometry of the existing slope adjacent to the slided one was measured and samples were collected from the site. The in-situ moisture content was 14% and dry unit weight was 18.63 kN/m3. Unconfined compression tests and unconsolidated-undrained (UU) triaxial tests were performed on samples reconstituted at in-situ dry unit weight, standard Proctor and modified Proctor maximum dry unit weights. The test results show that the shear strength and deformation parameters, i.e., undrained shear strength, angle of internal friction and deformation modulus decreased from 200 kPa to 90 kPa, 23° to 12° and 51 MPa to 32 MPa, respectively, with an increase in the percentage of saturation from 35% to 95% at a specific dry unit weight. The slope was also modeled in GeoStudio for limit equilibrium analysis, and slope stability analysis was performed using the values of undrained shear strength and the angle of internal friction as determined in the laboratory at varying degrees of saturation. The limit equilibrium analysis showed that the factor of safety reduces from 1.854 to 0.866 as the saturation of material increases from 35% to 95%. The results also suggest that, as the percentage of saturation increases above 85%, the soil loses its shear strength significantly and gains in bulk unit weight, so at this stage the material starts sliding. Additionally, slope stability analysis was carried out by changing the slope geometry in three different ways, i.e., by reducing the height of the slope, adding a counterweight at the toe of the slope and by making benches on the slope. The results of GeoStudio analysis showed that the slope will be stable even above 85% degree of saturation. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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20 pages, 8090 KiB  
Article
Comparison of DEM Models with Different Elemental Dimensions for TBM Disc Cutter Rock Fragmentation
by Chen Xu, Yujie Zhu, Danqing Song, Xiaogang Guo, Xiaoli Liu, Enzhi Wang and Runhu Lu
Sustainability 2022, 14(19), 12909; https://doi.org/10.3390/su141912909 - 10 Oct 2022
Cited by 2 | Viewed by 1536
Abstract
Disc cutters are the dominant tool used in the excavation of hard rock formations in any underground construction application, such as when tunneling using tunnel-boring machines (TBM), as well as in shaft- and raise boring operations. Optimization of the cutting geometry of a [...] Read more.
Disc cutters are the dominant tool used in the excavation of hard rock formations in any underground construction application, such as when tunneling using tunnel-boring machines (TBM), as well as in shaft- and raise boring operations. Optimization of the cutting geometry of a given disc cutter for application in a rock formation often involves full-scale cutting tests, which is a difficult and costly proposition. An alternative to full-scale testing is the numerical simulation of TBM disc cutters for optimization under different settings. Recent efforts in the field of numerical simulations of rock cutting have shown the relative success of discrete element models, such as particle flow code (PFC), to simulate two- and three-dimensional rock fragmentation. This study is focused on a sensitivity analysis of PFC simulation of rock-cutting relative to the size of the elements. The calculated cutting forces were compared with the recorded forces under various conditions during full-scale tests using a linear cutting machine (LCM) on Colorado red granite (CRG). The estimated cutting coefficient and specific energy in the LCM tests and simulations showed good correlations, which validates the numerical simulation results. Two- and three-dimensional models showed that two-dimensional numerical models can offer a qualitative assessment of crack development, whereas three-dimensional models could be used to estimate the specific energy when cutting. The results can help in predicting the cutting forces in different rocks and ultimately improving disc-cutter geometry and cutter-head design. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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31 pages, 10174 KiB  
Article
A Systematic Review of the Relationship between Geotechnics and Disasters
by Joselyne Solórzano, Fernando Morante-Carballo, Néstor Montalván-Burbano, Josué Briones-Bitar and Paúl Carrión-Mero
Sustainability 2022, 14(19), 12835; https://doi.org/10.3390/su141912835 - 08 Oct 2022
Cited by 6 | Viewed by 4283
Abstract
Landslides, earthquakes, and other natural events can change the landscape and generate human and economic losses, affecting transportation and public service infrastructure. In every geotechnical project, the investigation phase plays a fundamental role in reducing the risk of occurrence and mitigating catastrophes. As [...] Read more.
Landslides, earthquakes, and other natural events can change the landscape and generate human and economic losses, affecting transportation and public service infrastructure. In every geotechnical project, the investigation phase plays a fundamental role in reducing the risk of occurrence and mitigating catastrophes. As a result, governments have created entities to study disasters and identify triggering factors that generate huge losses worldwide. This research aims to conduct a systematic review of the relationship between geotechnics and disasters through bibliometric techniques, scientific production evaluation, and case studies analysis to recognize key topics, methods, and thematic development of the research worldwide. The research methodology consisted of three steps: (1) Database analysis, selection, and combination, (2) bibliometric analysis, and (3) systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. The systematic review with bibliometric analysis collected data from 1973 to 2021, with 1299 academic publications indexed in the Scopus and WoS database. These results indicated a growing trend of annual publications on disasters and their relationship with geotechnical studies, highlighting current issues and technological innovation. The main research trends in disaster risk assessment were topics mainly linked to landslides, earthquakes, liquefaction, and inappropriate analysis models with applications of geophysical methods, laboratory tests, remote sensing, and numerical models. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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15 pages, 30361 KiB  
Article
Comparison of Effects between Different Weight Calculation Methods for Improving Regional Landslide Susceptibility—A Case Study from Xingshan County of China
by Bo Cao, Qingyi Li and Yuhang Zhu
Sustainability 2022, 14(17), 11092; https://doi.org/10.3390/su141711092 - 05 Sep 2022
Cited by 2 | Viewed by 1270
Abstract
The information value (IV) model is a conventional method for landslide susceptibility prediction (LSP). However, it is inconsistent with the actual situation to regard all conditioning factors as equally weighted in the modeling process. In view of this, this paper studied the optimization [...] Read more.
The information value (IV) model is a conventional method for landslide susceptibility prediction (LSP). However, it is inconsistent with the actual situation to regard all conditioning factors as equally weighted in the modeling process. In view of this, this paper studied the optimization effect of different weight calculation methods for IV model. Xingshan County, a typical landslide-prone area located in Hubei Province, China, was taken as a case study. The procedure was as follows: First, six conditioning factors, including elevation, slope angle, aspect, curvature, distance to river, and distance to road, were selected to form an evaluation factor library for analyzing the landslide susceptibility. Then, the weight of factors was calculated by fuzzy analytical hierarchy process (FAHP) and principal component analysis (PCA). On this basis, combined with the IV model, two weighted IV models (FAHP-IV model and PCA-IV model) were formed for LSP. The results shows that the optimization effect of PCA was the best. Moreover, compared with the IV-only model (AUC = 0.71), the FAHP-IV model (AUC = 0.76) and PCA-IV model (AUC = 0.79) performed better. The outcome also provided a feasible way for the study of regional LSP. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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18 pages, 11841 KiB  
Article
Dynamic Response Mechanism of Silt Ground under Vibration Load
by Zhanfei Gu, Hailong Wei, Zhikui Liu and Mingfei Zhang
Sustainability 2022, 14(16), 10335; https://doi.org/10.3390/su141610335 - 19 Aug 2022
Cited by 2 | Viewed by 1095
Abstract
The frequent vibration loads during the operation of trains can cause vibration deformation of the tunnel structure and surrounding weak strata, thereby endangering the safe operation of trains. The purpose of this paper is to study the dynamic response of surrounding soil layers [...] Read more.
The frequent vibration loads during the operation of trains can cause vibration deformation of the tunnel structure and surrounding weak strata, thereby endangering the safe operation of trains. The purpose of this paper is to study the dynamic response of surrounding soil layers caused by train vibrations through the finite difference method with FLAC3D. Based on existing research, we studied the artificially deterministic exciting force function. Then, we simulated the tunnel working conditions of a train with a 3D model, and applied the artificially deterministic exciting force function to the tunnel model. To study the vibration caused by trains in silty soil, we divided the trains into two cases, one-way and two-way. We compared the displacement–time curves of one-way and two-way trains. When the horizontal distance between the monitoring point and the vibration source increases, the peak value of the displacement–time curve decreases. As the speed of the train increases, the peak value of the displacement–time curve increases. The vertical displacement of the ground under the dynamic load of the two-way train is greater than that of the one-way train. In the acceleration–time curve, there is a lag in the ground acceleration response. The faster the speed of the subway train, the greater the peak value of the acceleration–time curve. This study can provide a guide for the evaluation and prevention of ground vibration subsidence and uneven subsidence of strata in the silt area of the Yellow River Region. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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21 pages, 8722 KiB  
Article
Failure Mechanism and Stability Control Technology of Slope during Open-Pit Combing Underground Extraction: A Case Study from Shanxi Province of China
by Shuaihang Shi, Zizheng Guo, Peng Ding, Yabin Tao, Hui Mao and Zhichao Jiao
Sustainability 2022, 14(14), 8939; https://doi.org/10.3390/su14148939 - 21 Jul 2022
Cited by 2 | Viewed by 1576
Abstract
With the development of society, the demand for mineral resources is gradually increasing, and the current situation of decreasing total resources dictates the inevitable interaction between open-pit combing underground extraction (OPUG) in time and space. In this research, we took the Anjialing coal [...] Read more.
With the development of society, the demand for mineral resources is gradually increasing, and the current situation of decreasing total resources dictates the inevitable interaction between open-pit combing underground extraction (OPUG) in time and space. In this research, we took the Anjialing coal mine in Shanxi Province of China as a case study, and tested the physical and mechanical properties of coal rocks in the laboratory. The similarity criterion was used to build a similar experimental model for the deformation evolution of the slope of the open-pit mine section; the digital scattering method was used to test the influence of the underground mining process parameters on the deformation evolution of the open-pit slope. The results showed that there was an obvious distribution of “three zones” above the mining goaf, namely, a collapse zone, fracture zone, and slow subsidence zone. When the mining face was continuously advanced towards the bottom of the open pit, the supporting stress of the mining face transferred to the side of the open-pit slope. Additionally, large displacement and stress concentration were observed on the slope near the stoping line, which caused the slope body to move along the uppermost part of the slope first, and thereafter along the lower part. Various techniques for slope stability control are discussed, including the optimization of spatial and temporal relationships between open-pit and underground mining, the optimization of mining plans, and the use of monitoring and early warning systems. The results can provide a guide for slope stability control of similar open-pit mines in the process of mining coal resources. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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22 pages, 5302 KiB  
Article
Landslide Hazard Assessment Methods along Fault Zones Based on Multiple Working Conditions: A Case Study of the Lixian–Luojiabu Fault Zone in Gansu Province (China)
by Wei Feng, Yaming Tang and Bo Hong
Sustainability 2022, 14(13), 8098; https://doi.org/10.3390/su14138098 - 02 Jul 2022
Cited by 3 | Viewed by 1367
Abstract
Traditional landslide hazard assessment methods generally use the same evaluation model to carry out assessments under different working conditions. Due to the differences in landslide influence factors and model calculation methods considered under different working conditions, the evaluation results obtained using traditional methods [...] Read more.
Traditional landslide hazard assessment methods generally use the same evaluation model to carry out assessments under different working conditions. Due to the differences in landslide influence factors and model calculation methods considered under different working conditions, the evaluation results obtained using traditional methods are different from those of real-world scenarios. Therefore, research on optimal landslide hazard assessment methods for different working conditions is important for disaster prevention and mitigation in areas along fault zones. Taking the section along the Lixian–Luojiabu fault zone in Gansu province in China as the research area, a landslide hazard assessment was carried out under rainfall and earthquake conditions. A method based on the fractal theory–information coupling model is proposed for the rainfall condition, and a method based on an improved Newmark model considering matric suction is proposed for the earthquake condition. Under the rainfall condition, a landslide hazard assessment was carried out using the information model, the logistic regression model, the fractal theory model, the logistic regression–information coupling model and the fractal theory–information coupling model. Meanwhile, under the earthquake condition, an assessment was carried out using the traditional Newmark model and the improved Newmark model considering matric suction. Finally, the ROC curve and Kappa coefficient were used to test the accuracy of these evaluation models and to determine the optimal model under different working conditions. The results showed that the fractal theory–information coupling model had the largest AUC value and Kappa coefficient value under the rainfall condition (0.856 and 0.807, respectively). The test value of the logistic regression–information coupling model was second, and the values of the other three models were all lower than 0.8. This shows that the evaluation of the fractal theory–information coupling model is better than those of the other models under the rainfall condition. The AUC value and Kappa coefficient of the improved Newmark model under the earthquake condition were 0.805 and 0.794, respectively, which were larger than the test values of the traditional Newmark model. This shows that the evaluation of the proposed model is better than that of the traditional Newmark model under the earthquake condition. These research results provide a reference for landslide hazard assessments in areas with similar characteristics. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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37 pages, 10857 KiB  
Article
Comprehensive Fracture Model of Reservoir Ice Layers in the Northeastern Cold Region of China
by Xiaozhou Liu, Ben Li, Yaodan Zhang and Chen Zhang
Sustainability 2022, 14(12), 7326; https://doi.org/10.3390/su14127326 - 15 Jun 2022
Viewed by 1229
Abstract
Meteorological and hydrological changes have an important influence on the ice formation mechanism and the detailed structure of ice materials in cold reservoirs, and directly determine the mechanical properties of ice materials. Based on long-term meteorological and hydrological monitoring data, and detailed structural [...] Read more.
Meteorological and hydrological changes have an important influence on the ice formation mechanism and the detailed structure of ice materials in cold reservoirs, and directly determine the mechanical properties of ice materials. Based on long-term meteorological and hydrological monitoring data, and detailed structural evolution analysis of ice materials, combined with fracture mechanics and energy methods, a comprehensive fracture model of ice materials in cold regions is established. At the same time, the fracture mechanics test results and simulation results of ice materials are compared, and the model is finally optimized accurately to provide theoretical support for the study of the mechanical mechanism of ice materials. Full article
(This article belongs to the Special Issue Sustainability in Geology and Civil Engineering)
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