Experimental Analysis of Bearing Capacity of Basalt Fiber Reinforced Concrete Short Columns under Axial Compression
作者：
Wang, Xinzhong;Yang, Yiming;Yang, Rihua;Liu, Peng
期刊：
Coatings ,2022年12(5):654- ISSN：2079-6412
通讯作者：
Yang, Y.;Liu, P.
作者机构：
[Yang, Rihua; Wang, Xinzhong; Yang, Yiming] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Wang, Xinzhong] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;[Liu, Peng] Cent South Univ, Sch Civil Engn, Changsha 410013, Peoples R China.
通讯机构：
[Yiming Yang] S;[Peng Liu] A;Authors to whom correspondence should be addressed.<&wdkj&>School of Civil Engineering, Central South University, Changsha 410013, China<&wdkj&>School of Civil Engineering, Hunan City University, Yiyang 413000, China<&wdkj&>Authors to whom correspondence should be addressed.
关键词：
basalt-fiber-reinforced concrete;concrete compressive strength;construction performance;ultimate bearing capacity;finite element analysis
摘要：
Adding basalt fiber to concrete can improve the mechanical properties of concrete, and it is also one of the best ways to enhance the ultimate bearing capacity of concrete structure. In this paper, the construction performance and the compressive strength of basalt-fiber-reinforced concrete (BFRC) with five kinds of fiber lengths and eight kinds of fiber volume content subjected to an axial load are systematically investigated. The optimum fiber length and fiber volume content are obtained by comprehensively considering the construction performance and compressive strength. Moreover, the prediction model and finite element analysis method of the ultimate bearing capacity of basalt-fiber-reinforced concrete are developed. The results show that the optimum fiber length is about 12–24 mm and the fiber volume content is 0.15%. Adding an appropriate amount of basalt fiber can effectively improve the ultimate bearing capacity of concrete short columns, with maximum and average increases of 28% and 24%, respectively. In addition, the comparison with the experimental results shows that both the proposed prediction method and the finite element modeling method have good applicability, and they can be used to predict the ultimate bearing capacity of the BRFC short columns in practical engineering. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
语种：
英文
展开
Seismic design of rectangular/square columns in SDOF systems based on their damage performance
作者：
Wang, Yukui;Liu, Zhefeng;Zhang, Dan;Hu, Zhangqi;Yu, Dong
期刊：
Science Progress ,2022年105(4) ISSN：0036-8504
通讯作者：
Zhefeng Liu
作者机构：
[Wang, Yukui; Zhang, Dan; Hu, Zhangqi; Yu, Dong] Hunan City Univ, Coll Civil Engn, Yiyang 413099, Peoples R China.;[Liu, Zhefeng; Wang, Yukui] Changsha Univ Sci & Technol, Coll Civil Engn, Changsha 410004, Peoples R China.
通讯机构：
[Zhefeng Liu] C;College of Civil Engineering, Changsha University of Science & Technology, Changsha, 410004, China
关键词：
Performance design;reinforced concrete column;energy dissipation capacity;damage index;performance index limits
摘要：
The quantitative relationship between the energy dissipation capacity of RC members and displacement deformation, cumulative energy dissipation and structural design parameters were established by the research group in the early stage, and then the damage index based on energy dissipation capacity and performance index limits were proposed. Based on the existing research, the seismic design method of RC square/rectangular column members for SDOF systems based on damage performance is proposed, and the method is introduced by an example. It is found that the seismic design method establishes a quantitative relationship between the structural design parameters and seismic parameters, which is convenient to guide the structural design. The increase in the ratio of transverse reinforcement can reduce the damage to RC column members, but when the ratio of transverse reinforcement exceeds a certain threshold value, the damage reduction effect is not obvious. The increase of the earthquake duration can aggravate the development of the damage to the RC column members, and the increasing effect is first fast and then slow. This seismic design method can make up for the deficiency that the duration effect is not considered in the current seismic code.
语种：
英文
展开
Fine grid model for the dielectric characteristics of ground-penetrating radar in mixed media
作者：
Ling, Tonghua;He, Wenchao;Liu, Xianjun;Zhang, Sheng;Huang, Fu;...
期刊：
Geophysical Prospecting ,2022年70(6):1052-1065 ISSN：0016-8025
通讯作者：
He, Wenchao(hewenchao1224@stu.csust.edu.cn)
作者机构：
[Ling, Tonghua; Liu, Xianjun; He, Wenchao; Huang, Fu; Hua, Fei] Changsha Univ Sci & Technol, Coll Civil Engn, Changsha 410114, Peoples R China.;[Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Wenchao He] C;College of Civil Engineering, Changsha University of Science and Technology, Changsha, 410114 China
关键词：
Ground-penetrating radar;Finite difference methods;Numerical modelling;Signal processing;Wavelet
摘要：
The Fisher–Yates random shuffling algorithm combined with the finite-difference time-domain method is proposed to construct a fine grid model for the forward simulation of ground-penetrating radar in mixed media. First, the finite-difference time-domain method was used to divide the coarse grid model into several fine grid models by conforming to the boundary conditions of different media, and the corresponding dielectric parameters were assigned to Yee cells in each fine grid model. Then, the Fisher–Yates random shuffling algorithm was used to randomly scramble all Yee cells with equal probability, and the array of scrambled Yee cells was recombined into a coarse grid model. Finally, the geoelectric model of mixed media was generated with the finite-difference time-domain method, and a ground-penetrating radar image excited by electromagnetic wave pulses was obtained. To explore the characteristic signals and dielectric properties of the ground-penetrating radar electromagnetic response in mixed media, image entropy theory was used to describe the ground-penetrating radar image, and waveform analysis and wavelet transform mode maximum methods were used to analyse the single-channel ground-penetrating radar signal of the mixed media. The results showed that the Fisher–Yates random shuffling–finite-difference time-domain method can be used to construct a valid and stable fine grid model for simulating ground-penetrating radar in mixed media. The model effectively inhibits electromagnetic attenuation and energy dissipation, and the wavelet transform mode maximum method explains the relative dielectric permittivity distribution of the mixed media. The findings of this study can be used as a theoretical basis for correcting radar parameters and interpreting images when ground-penetrating radar is applied to mixed media. © 2022 European Association of Geoscientists & Engineers.
语种：
英文
展开
A Generalized Load-Transfer Modeling Framework for Tensioned Anchors Integrating Adhesion-Friction-Based Interface Model
作者：
Chen, Changfu;Zhu, Shimin;Zhang, Genbao;Morsy, Amr M.;Zornberg, Jorge G.;...
期刊：
International Journal of Geomechanics ,2022年22(5) ISSN：1532-3641
通讯作者：
Zhang, GB
作者机构：
[Zhu, Shimin; Mao, Fengshan; Chen, Changfu] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China.;[Zhang, Genbao; Zhang, GB] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Hunan, Peoples R China.;[Morsy, Amr M.] Loughborough Univ, Sch Architecture Bldg & Civil Engn, Loughborough LE11 3TU, Leics, England.;[Zornberg, Jorge G.] Univ Texas Austin, Dept Civil Architectural & Environm Engn, Austin, TX 78712 USA.
通讯机构：
[Zhang, GB ] H;Hunan City Univ, Coll Civil Engn, Yiyang 413000, Hunan, Peoples R China.
关键词：
Element anchoring interface;Interface bond-slip model;Load-transfer modeling framework;Pullout response;Tensioned anchors
摘要：
The load-transfer mechanism of tensioned anchors is primarily concerned with in-service performance, which depends on the bond-slip behavior of anchoring interface. Because the interface bond-slip behavior is conventionally modeled using epistemic experience of specific researchers and/or back analysis of specific in situ testing results, it is challenging to develop a straightforward load-transfer analysis with extensive applicability. A generalized load-transfer modeling framework was implemented in this work by incorporating a versatile interface bond-slip model that can be derived from experimental characterization of respective types of element-anchoring interface. The adhesion and friction were modeled with interface slip to constitute the interface bond using rational and exponential functions, respectively. The pullout tests on element-scale and large-scale specimens of a typical anchor type (i.e., tensioned steel tube embedded in cemented soils) were carried out to calibrate the parameters of the interface model and to validate the predicting capability of the modeling framework, respectively. In addition, the versatility of this load-transfer modeling framework was examined for two other anchor types reported in the literature (i.e., tensioned rock anchor and tensioned GFRP anchor embedded in sands). The consistent good agreements between predictions and measurements of these anchor types verified the effectiveness and applicability of the generalized load-transfer modeling framework. Based on the load-transfer analysis for the tensioned steel tube in model testing, a parametric study was performed to investigate the impact of axial stiffness and bond length on load-transfer responses of the tensioned anchor. © 2022 American Society of Civil Engineers.
语种：
英文
展开
Analytical Reliability Evaluation Framework of Three-Dimensional Engineering Slopes
作者：
Zhang, Genbao;Zhu, Jianfeng;Chen, Changfu;Tang, Renhua;Zhu, Shimin;...
期刊：
Buildings ,2022年12(3) ISSN：2075-5309
通讯作者：
Zhu, JF
作者机构：
[Zhang, Genbao; Luo, Xiao] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Zhang, Genbao] Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;[Zhu, Jianfeng; Zhu, JF] Zhejiang Univ Sci & Technol, Coll Civil Engn & Architecture, Hangzhou 310023, Peoples R China.;[Zhu, Shimin; Chen, Changfu] Hunan Univ, Minist Educ, Key Lab Bldg Safety & Energy Efficiency, Changsha 410082, Peoples R China.;[Zhu, Shimin; Chen, Changfu] Hunan Univ, Coll Civil Engn, Changsha 410082, Peoples R China.
通讯机构：
[Zhu, JF ] Z;Zhejiang Univ Sci & Technol, Coll Civil Engn & Architecture, Hangzhou 310023, Peoples R China.
关键词：
three-dimensional reliability evaluation;response surface;Morgenstern-Price method;probability distribution
摘要：
An analytical three‐dimensional slope reliability evaluation framework was developed in this work independent of use of numerical simulations. The slope stability analysis was necessarily carried out by utilizing an extended three‐dimensional Morgenstern–Price method, which was characterized by analytical formulations and competitive computational efficiency. Incorporation of the presented stability analysis method into response surface methodology led to an effective slope reliability evaluation framework. The applicability and superiority of this framework was examined and validated using a real complicated landslide case reported in practice, and a hypothetical slope example widely adopted in the literature. The impact of correlation coefficients and probability distribution patterns on the slope reliability assessment results was further addressed to derive additional benefits of this framework. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
语种：
英文
展开
Effects of Stiffener Type on Fatigue Resistance of Steel-UHPC Composite Bridge Decks
作者：
Sun, Xiugui;Hu, Jianhua;Li, Yu;Huang, Guoping
期刊：
Advances in Civil Engineering ,2022年2022 ISSN：1687-8086
通讯作者：
Hu, JH;Huang, GP
作者机构：
[Sun, Xiugui] Hunan Univ, Changsha 410082, Peoples R China.;[Hu, JH; Hu, Jianhua] Hunan Commun & Water Conservancy Grp LTD, Changsha 410000, Peoples R China.;[Li, Yu] Survey & Design Inst Co Ltd, Hunan Prov Commun Planning, Changsha 410000, Peoples R China.;[Huang, Guoping] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Hu, JH ; Huang, GP ] H;Hunan Commun & Water Conservancy Grp LTD, Changsha 410000, Peoples R China.;Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
摘要：
Recent research showed that ultrahigh-performance concrete (UHPC) and orthotropic steel bridge decks could be integrated to form steel-UHPC composite sections offering superior load-carrying capacity and fatigue resistance. This study investigates the effects of longitudinal stiffener types on the fatigue resistance of steel-UHPC composite sections. Three types of longitudinal stiffeners were compared, including U-ribs, bulb flat ribs, and plate ribs. Finite element analysis and full-scale fatigue tests were performed to investigate the load-carrying capacity and fatigue resistance of the composite bridge decks with different stiffeners. Besides, the proposed steel-UHPC composite bridge decks were compared with conventional orthotropic steel decks. The results show that steel box girders with bulb flat rib composite deck have reasonable fatigue resistance, construction efficiency, and economic benefits. This study is expected to promote the design and evaluation of economic steel-UHPC composite bridge decks to achieve higher mechanical performance and long-term durability. © 2022 Xiugui Sun et al.
语种：
英文
展开
Interface creep behavior of tensioned GFRP tendons embedded in cemented soils
作者：
Chen, C.;Zhu, S.;Zhang, G.;Morsy, A. M.;Zornberg, J. G.;...
期刊：
Geosynthetics International ,2022年29(3):241-253 ISSN：1072-6349
通讯作者：
Zhang, G
作者机构：
[Zhu, S.; Chen, C.; Huang, J.] Hunan Univ, Minist Educ, Key Lab Bldg Safety & Energy Efficiency, Changsha, Peoples R China.;[Zhu, S.; Chen, C.; Huang, J.] Hunan Univ, Coll Civil Engn, Changsha, Hunan, Peoples R China.;[Zhang, G.] Hunan City Univ, Coll Civil Engn, Yiyang, Hunan, Peoples R China.;[Morsy, A. M.] Loughborough Univ, Sch Architecture Bldg & Civil Engn, Loughborough, Leics, England.;[Morsy, A. M.] Cairo Univ, Dept Civil Engn, Giza 12613, Egypt.
通讯机构：
[Zhang, G ] H;Hunan City Univ, Coll Civil Engn, Yiyang, Hunan, Peoples R China.
关键词：
Geosynthetics;Glass fiber-reinforced polymer;Cemented soils;Interface creep behavior;Burgers model
摘要：
This paper presents an experimental investigation and modeling of interface creep behavior of glass fiber-reinforced polymer (GRFP) tendons embedded in cemented soils. Rapid and creep pullout tests were carried out on GRFP tendons embedded in cemented soils using a specially developed pullout setup. Interface creep displacement responses for specimens with two different water-cement ratios were derived under various interface shear stress conditions. A modified Burgers model was developed to characterize the interface creep behavior by incorporating a time-dependent viscosity coefficient. This viscosity coefficient was calibrated using creep rate variation obtained experimentally. Regression fittings on a part of interface creep measurements were conducted to determine the value of the parameters of the interface creep model. Additional interface creep measurements were used to validate the applicability of the presented creep testing protocol and the effectiveness of the rheological modeling was validated. © 2021 Thomas Telford Ltd.
语种：
英文
展开
Theoretical and experimental investigations of anchoring force loss behavior for prestressed ground anchors
作者：
Zhu, Shimin;Chen, Changfu;Zhang, Genbao;Du, Cheng
期刊：
Canadian Geotechnical Journal ,2022年59(9):1587-1601 ISSN：0008-3674
通讯作者：
Chen, Changfu(cfchen@hnu.edu.cn)
作者机构：
[Du, Cheng; Zhu, Shimin; Chen, Changfu] Hunan Univ, Key Lab Bldg Safety & Energy Efficiency, Minist Educ, Changsha 410082, Hunan, Peoples R China.;[Du, Cheng; Zhu, Shimin; Chen, Changfu] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China.;[Zhang, Genbao] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Hunan, Peoples R China.
通讯机构：
[Chen, C.] K;Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education, Hunan, China
关键词：
anchoring force loss;load transfer;prestressed ground anchor;relaxation
摘要：
Anchoring force loss is critically concerned for the in-service performance of prestressed ground anchors. This time-dependent loss of pretension exerted at the anchor head is caused primarily by stress relaxation, which integrally manifests the rheological properties of the anchor and the geomaterial in which the anchor is embedded. A load-transfer modeling framework was established to derive the time-dependent anchoring force response. The modeling parameters were directly calibrated via element-scale pullout stress relaxation test using a specially developed setup. The applicability and effectiveness of this analytical modeling framework were verified via large-scale laboratory model tests and in situ tests of prestressed an-chors. The predictions derived using the presented modeling framework were in good agreement with measurements in both laboratory model tests and in situ tests, particularly for evolutions of anchoring force over time. Sensitivity evaluation of the model parameters was performed to study their respective impact on the anchoring force loss response. This work can provide insights into the understanding of the anchoring force loss behavior of prestressed ground anchors and facilitate their design practice for in-service performance. © 2022 The Author(s).
语种：
英文
展开
An Improved Model to Calculate Pullback Force of Trenchless Horizontal Directional Drilling Pipeline
作者：
Liang, Xiao-qiang;Hu, Da;Li, Yong-suo;Yang, Xian;Jiang, Lei;...
期刊：
Advances in Civil Engineering ,2022年2022 ISSN：1687-8086
通讯作者：
Hu, D
作者机构：
[Zhang, Yun-yi; Liang, Xiao-qiang; Li, Yong-suo; Hu, Da; Hu, D] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;[Zhang, Yun-yi; Liang, Xiao-qiang; Hu, Da; Hu, D] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Zhang, Yun-yi; Liang, Xiao-qiang; Hu, Da; Hu, D] Cent South Univ, Minist Educ, Key Lab Metallogen Predict Nonferrous Met & Geol, Changsha 410083, Peoples R China.;[Yang, Xian] Hunan Univ Sci & Technol, Sch Resource Environm & Safety Engn, Xiangtan 411201, Hunan, Peoples R China.;[Jiang, Lei] Changsha Metro Grp Co Ltd, Changsha 410007, Peoples R China.
通讯机构：
[Hu, D ] H;Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;Cent South Univ, Minist Educ, Key Lab Metallogen Predict Nonferrous Met & Geol, Changsha 410083, Peoples R China.
摘要：
In the pullback operation of horizontal directional drilling pipeline crossing, the existing calculation and prediction models of pullback force are relatively simple. Each pullback force maze greatly simplifies the wellbore trajectory and fails to make a detailed analysis of the pipeline stress and external resistance when the pipeline is pulled back in each characteristic trajectory area. The factors considered are relatively simple. Therefore, it is necessary to improve the calculation method of pullback force. This paper aims to establish an improved model, enhancing the earth pressure calculation method of unloading arch and winch calculation method, and carries out an example calculation of the improved formula. Therefore, it is necessary to study the pullback process of horizontal directional drilling pipeline. Firstly, this paper analyzes the calculation method of pullback force in horizontal directional drilling; studies the calculation formula and principle of common pullback force through examples; obtains the advantages, disadvantages, and applicable scope of different formulas; and improves the calculation model of pullback force and step resistance. The numerical simulation of the step crossing process is carried out, and the variation law of local stress and strain of the pipeline and relevant conclusions are obtained. The results show that the estimates of the winch calculation method are close to the actual pullback load of the project. The earth pressure calculation method of the unloading arch and the winch calculation method are improved, and a more stable and reliable calculation formula is obtained, which provides more valuable calculation data for the actual project. In the process of pullback, the pipeline will encounter step resistance after passing through the soft and hard staggered stratum, which will suddenly increase the increment of pipeline pullback force and lead to engineering accidents. If the pullback load suddenly increases and then decreases, it may encounter similar pipeline collision accidents. At the same time, emergency measures can be taken to prevent the crossing accident and ensure the safe pullback of the pipeline. © 2022 Xiao-qiang Liang et al.
语种：
英文
展开
Research on Metallogenic System and Deposit Genesis: With Zhacun Goldmine in Weishan County of Yunnan as an Example
作者：
Ding, Xing-yu;Hu, Wen-jun;Chang, Yi
期刊：
Geofluids ,2022年2022 ISSN：1468-8115
通讯作者：
Chang, Y.;Hu, W.-J.
作者机构：
[Ding, Xing-yu] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Hunan, Peoples R China.;[Hu, Wen-jun] Geol Environm Monitoring Inst Yunnan Prov, Kunming 650216, Yunnan, Peoples R China.;[Chang, Yi] East China Univ Technol, Sch Civil & Architecture Engn, Nanchang 330013, Jiangxi, Peoples R China.
通讯机构：
[Wen-jun Hu] G;[Yi Chang; Xing-yu Ding] S;School of Civil & Architecture Engineering,East China University of Technology,Nanchang,China<&wdkj&>Geology Environmental Monitoring Institute in Yunnan Province,Kunming,650216 Yunnan,China<&wdkj&>School of Civil Engineering,Hunan City University,Yiyang,China
关键词：
Introduction;Materials and Methods;Results;Discussion;Conclusion;Abstract;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interests;Authors’ Contributions;Funding Statement;Acknowledgements;Acknowledgments;Supplementary Materials;Reference;Dataset Description;Dataset Files;Abstract;Introduction;Introduction and Materials;Introduction and Methods;Materials;Materials and Methods;Methods;Results;Discussion;Results and Discussion;Discussion and Conclusion;Results and Conclusion;Conclusion;Conclusions;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interest;Authors’ Contributions;Funding Statement;Acknowledgements;Supplementary Materials;References;Appendix;Abbreviations;Preliminaries;Introduction and Preliminaries;Notation;Proof of Theorem;Proofs;Analysis of Results;Examples;Numerical Example;Applications;Numerical Simulation;Model;Model Formulation;Systematic Palaeontology;Nomenclatural Acts;Taxonomic Implications;Experimental;Synthesis;Overview;Characterization;Background;Experimental;Theories;Calculations;Model Verification;Model Implementation;Geographic location;Study Area;Geological setting;Data Collection;Field Testing;Data and Sampling;Dataset;Literature Review;Related Works;Related Work;System Model;Methods and Data;Experimental Results;Results and Analysis;Evaluation;Implementation;Case Presentation;Case Report;Search Terms;Case Description;Case Series;Background;Limitations;Additional Points;Case;Case 1;Case 2 etc.;Concern Details;Retraction Details;Copyright;Related Articles
摘要：
This paper mainly takes Zhacun goldmine as the research object and carries out research on the metallogenic system and genesis of the deposit in the area. The research methods are as follows: according to the geological characteristics of the metallogenic mining area in the Zhacun goldmine, combined with the comparative analysis of the metallogenic age, alteration characteristics and lithology between the Zhacun goldmine and the Lianhuashan alkali rich rock mass, and the analysis of the isotopic data in the Zhacun goldmine, this paper demonstrates that the magmatic activity of the Lianhuashan quartz monzonite porphyry plays an important role in the mineralization of this area, which is both an important ore source and fluid source. It is also the main heat source driving the circulation of ore-forming fluid. On this basis, through the analysis of the metallogenic elements in the area, the metallogenic system model of Zhacun goldmine is constructed. It is considered that under the action of long-term horizontal compressive stress, the atmospheric precipitation infiltrated into the formation continued to penetrate along the fractures and fissures to deep crust and finally mixed with the magmatic water sealed in the thick formation. During this period, a series of shallow and ultrashallow porphyry mass intruded, providing heat source and part of the ore-forming materials and resulting in incomplete homogenization under high temperature and high pressure, which formed highly mineralized mixed water. Under the combined action of long-term compressive stress and various deep thermal dynamics, these mineral fluids migrated along the buried deep faults near the core of the duplex anticline to the upper part of the crust. When the metal elements in these ore fluids migrated over long distances to the nappe fault zone of the gold-bearing fracture zone, the gold began to precipitate, and the native gold and the coarse-grained pyrite and quartz formed at the same time or earlier started to fill the fracture zone along the fissures and accumulate into minerals. Then, through the analysis of metallogenic conditions, gold mineralization process, and genetic mechanism of the deposit, it is proposed that the genetic type of the ore deposit in this area is magmatic mesothermal-epithermal gold deposit. The establishment of metallogenic system model in Zhacun goldmine will provide theoretical and practical guidance for deep and peripheral prospecting prediction in the area, carry out targeted and reasonable prediction, and improve prospecting effectiveness. © 2022 Xing-yu Ding et al.
语种：
英文
展开
Effect of Rheological Mesoparameters on Shear Mechanical Behavior of Joints
作者：
Zhou, Kefeng;Liu, Sheng;Cheng, Yanhui
期刊：
Geofluids ,2022年2022 ISSN：1468-8115
通讯作者：
Zhou, K.
作者机构：
[Liu, Sheng; Zhou, Kefeng] Changsha Univ Sci & Technol, Sch Traff & Transportat Engn, Changsha 410114, Hunan, Peoples R China.;[Cheng, Yanhui] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Hunan, Peoples R China.;[Cheng, Yanhui] Cent South Univ, Sch Resource Safety Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Zhou, K.] S;School of Traffic and Transportation Engineering, Changsha University of Science and Technology, Hunan, Changsha, China
摘要：
Under natural conditions, joint failure usually occurs after long-term loading rather than short-term loading. In order to prevent rock mass failure caused by creep behavior, bolt is widely used as a mature and effective reinforcement method. Therefore, it is necessary to consider the rheological effect of bolted joint. In this paper, the particle flow code (PFC) was used to study the effect of mesoparameters on the rheological shear mechanical behavior of joints without bolts and with bolts. The effects of mesoparameters such as Maxwell elastic coefficient Em, Maxwell viscosity coefficient Cm, Kelvin elastic coefficient Em, Kelvin viscosity coefficient Cm, and friction coefficient Fs were analyzed. The results show that Em and Fs mainly affect the instantaneous shear displacement, but have little effect on the rheological shear displacement. However, Cm, Ek, and Ck have little effect on the instantaneous shear displacement, and the sensitivity is mainly reflected in the rheological shear displacement. Em and Fs mainly affect the instantaneous shear displacement, but have little effect on the rheological shear displacement. However, Cm, Ek, and Ck have little effect on the instantaneous shear displacement, and the sensitivity is mainly reflected in the rheological shear displacement. Compared with the parameter sensitivity characteristics without bolt, the instantaneous shear displacement, shear stiffness, and steady rheological displacement under anchor condition are less affected by parameters, indicating that anchor can reduce the influence of joint parameters. © 2022 Kefeng Zhou et al.
语种：
英文
展开
Optimised neural network prediction of interface bond strength for GFRP tendon reinforced cemented soil
作者：
Zhang, Genbao;Chen, Changfu;Zhang, Yuhao;Zhao, Hongchao;Wang, Yufei;...
期刊：
Geomechanics and Engineering ,2022年28(6):599-611 ISSN：2005-307X
通讯作者：
Wang, YF
作者机构：
[Zhang, Genbao] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Hunan, Peoples R China.;[Wang, Yufei; Wang, YF] Chongqing Univ, Inst Smart City, Chongqing Univ Liyang, Zhenjiang 213300, Jiangsu, Peoples R China.;[Zhang, Genbao] Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Hunan, Peoples R China.;[Chen, Changfu] Hunan Univ, Minist Educ, Key Lab Bldg Safety & Energy Efficiency, Changsha 410082, Hunan, Peoples R China.;[Chen, Changfu] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Wang, YF ] C;Chongqing Univ, Inst Smart City, Chongqing Univ Liyang, Zhenjiang 213300, Jiangsu, Peoples R China.
关键词：
back propagation neural network;cemented soil;element pullout test;glass fibre reinforced polymer reinforcement;interface bond strength;machine learning;particle swarm optimisation
摘要：
Tendon reinforced cemented soil is applied extensively in foundation stabilisation and improvement, especially in areas with soft clay. To solve the deterioration problem led by steel corrosion, the glass fiber-reinforced polymer (GFRP) tendon is introduced to substitute the traditional steel tendon. The interface bond strength between the cemented soil matrix and GFRP tendon demonstrates the outstanding mechanical property of this composite. However, the lack of research between the influence factors and bond strength hinders the application. To evaluate these factors, back propagation neural network (BPNN) is applied to predict the relationship between them and bond strength. Since adjusting BPNN parameters is time-consuming and laborious, the particle swarm optimisation (PSO) algorithm is proposed. This study evaluated the influence of water content, cement content, curing time, and slip distance on the bond performance of GFRP tendon-reinforced cemented soils (GTRCS). The results showed that the ultimate and residual bond strengths were both in positive proportion to cement content and negative to water content. The sample cured for 28 days with 30% water content and 50% cement content had the largest ultimate strength (3879.40 kPa). The PSO-BPNN model was tuned with 3 neurons in the input layer, 10 in the hidden layer, and 1 in the output layer. It showed outstanding performance on a large database comprising 405 testing results. Its higher correlation coefficient (0.908) and lower root-mean-square error (239.11 kPa) were obtained compared to multiple linear regression (MLR) and logistic regression (LR). In addition, a sensitivity analysis was applied to acquire the ranking of the input variables. The results illustrated that the cement content performed the strongest influence on bond strength, followed by the water content and slip displacement. © 2022 Techno-Press, Ltd.
语种：
英文
展开
Girder Longitudinal Movement and Its Factors of Suspension Bridge under Vehicle Load
作者：
Huang, Guoping* ;Hu, Jianhua;Liu, Haibo;Sun, Xiugui
期刊：
Advances in Civil Engineering ,2021年2021 ISSN：1687-8086
通讯作者：
Huang, Guoping
作者机构：
[Sun, Xiugui; Hu, Jianhua; Huang, Guoping] Hunan Univ, Key Lab Wind & Bridge Engn Hunan Prov, Coll Civil Engn, Changsha 410082, Peoples R China.;[Huang, Guoping] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Hu, Jianhua; Liu, Haibo] Hunan Commun & Water Conservancy Grp Ltd, Changsha 410008, Peoples R China.;[Sun, Xiugui] Hunan Prov Commun Planning Survey & Design Istute, Changsha 410200, Peoples R China.
通讯机构：
[Huang, Guoping] H;Hunan Univ, Key Lab Wind & Bridge Engn Hunan Prov, Coll Civil Engn, Changsha 410082, Peoples R China.;Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
摘要：
Vehicle load may not only cause vertical deformation and vibration of suspension bridge but also lead to longitudinal deformation and vibration. And the longitudinal behavior is closely related to the durability of the girder end devices and the bending fatigue failure of suspenders. In this study, the longitudinal deformation behavior and longitudinal vibration of suspension bridge under vehicles, as well as the related influencing factors, are investigated. The underlying mechanism of girder longitudinal movement under the moving vehicles is revealed. Based on the simplified vehicle model of vertical concentrated force, the characteristics of main cable deformation and girder longitudinal displacement under vertical loads are analyzed first. Then, the longitudinal motion equation of the girder under vertical moving loads is derived. Finally, a single long-span suspension bridge is employed in the case study, and the girder longitudinal response and influencing factors are investigated based on both numerical simulation and field monitoring. Results indicate that the asymmetric vertical load leads to cable longitudinal deflection owing to the geometrically nonlinear characteristic of the main cable, leading to longitudinal movement of the girder. The results of field monitoring and numerical simulation indicate that the girder moves quasi-statically and reciprocates longitudinally with centimeter amplitude under normal operational loads. © 2021 Guoping Huang et al.
语种：
英文
展开
湘中白马山复式岩体成因及其成矿效应
作者：
Wang Chuan;Peng JianTang;Xu JieBiao;Yang JieHua;Hu A Xiang;...
期刊：
岩石学报 ,2021年37(3):805-829 ISSN：1000-0569
作者机构：
[Wang Chuan; Yang JieHua; Chen XianJia; Peng JianTang; Xu JieBiao] Cent South Univ, Sch Geosci & Infophys, MOE Key Lab Metallogen Predict Nonferrous Met & G, Changsha 410083, Peoples R China.;[Peng JianTang] Chinese Acad Sci, Inst Geochem, State Key Lab Ore Deposit Geochem, Guiyang 550002, Peoples R China.;[Hu A Xiang] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
关键词：
白马山复式岩体;印支期花岗岩;岩石成因;成矿效应;湘中地区;华南
摘要：
白马山复式岩体位于湘西雪峰山弧形构造隆起带与湘中白马山-龙山-紫云山EW向构造带的交汇处,由水车、龙潭、小沙江和龙藏湾超单元花岗岩组成。锆石LA-ICP-MS U-Pb同位素定年显示,水车、龙潭、小沙江、龙藏湾超单元花岗岩的侵位年龄分别为424.9±2.2Ma、228.2±1.3Ma、225.3±1.1Ma和215.0±1.2Ma。水车超单元形成于加里东期,其余3个超单元花岗岩均形成于印支晚期,首次系统搭建了白马山复式岩体的年代学格架。印支期龙潭和小沙江超单元花岗岩具有低硅、低碱、准铝质-弱过铝质的特点,显示较强的Rb、Th、U、Pb正异常和Nb、Sr、P、Ti负异常,具有较弱的负Eu异常（δEu为0.55～1.07）;富集Sr同位素[(87Sr/86Sr)i=0.719027～0.721297]、亏损Nd同位素[εNd（t）=-10.5～-9.4]和锆石Hf同位素[εHf（t）=-7.7～-4.1],具有古老的Nd同位素（1.76～1.85Ga）和Hf同位素（1.42～1.83Ga）二阶段模式年龄。相反,龙藏湾超单元花岗岩具有高硅、高碱、强过铝质的特点,显示较强的Rb、Th、U、Ta、Pb正异常和Ba、Nb、Sr、Ti负异常,显示强的负Eu异常（δEu=0.28～0.51）和高(87Sr/86Sr)i值（0.741441～0.748761）,具有负的εNd（t）值（-11.3～-10.7）和εHf（t）值（-11.5～-3.5）,Nd同位素（1.87～1.91Ga）和Hf同位素（1.47～1.97Ga）二阶段模式年龄更老。结合元素和同位素地球化学特征,可推断出龙潭和小沙江超单元花岗岩是华南古老地壳基底中基性变质火成岩混有变质沉积岩发生部分熔融形成的I型或者I-S过渡性质的花岗质岩石,而龙藏湾超单元花岗岩则由华南成熟度更高的古老地壳基底富粘土变沉积岩发生部分熔融形成的S型花岗岩。白马山复式岩体中印支期超单元花岗岩很可能是华南板块受印支板块碰撞挤压后地壳发生伸展减薄,由加厚的地壳发生部分熔融形成的。这些印支期花岗岩与其周缘的金、钨矿床在时、空上具有密切联系,可能具有良好的成矿潜力;湘中地区印支期花岗岩的成岩、成矿作用在强度和广度上可能远高于过去的传统认识。
语种：
中文
展开
Chloride diffusion and time to corrosion initiation of reinforced concrete structures
作者：
Peng, Jianxin;Tang, Huang;Xiao, Linfa;Cheng, Xiaokang;Zhang, Jianren
期刊：
Magazine of Concrete Research ,2021年73(15):757-770 ISSN：0024-9831
通讯作者：
Huang Tang
作者机构：
[Xiao, Linfa; Cheng, Xiaokang; Peng, Jianxin; Zhang, Jianren] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha, Hunan, Peoples R China.;[Tang, Huang] Hunan City Univ, Sch Civil Engn, Yingyang, Hunan, Peoples R China.;[Tang, Huang] Changsha Univ Sci & Technol, Ind Key Lab Transportat Infrastruct Secur Risk Ma, Changsha, Hunan, Peoples R China.
通讯机构：
[Huang Tang ] L;Lecturer, School of Civil Engineering, Hunan City University, Yingyang, Hunan, China;Industry Key Laboratory of Transportation Infrastructure Security Risk Management of Changsha University of Science and Technology, Changsha, Hunan, China (corresponding author: [email protected])
关键词：
compressive strength;durability-related properties;modelling
摘要：
The diffusion mechanism for chloride ions in concrete with varying water/cement ratio (w/c) is studied by chloride ion spray testing. A new model of chloride diffusion coefficient, which varies with the ingress depth of chloride ion and w/c, is developed. A spatial time-dependent reliability model of time to corrosion initiation (T-CI) for reinforced concrete (RC) structures is developed, considering spatial variability of geometric, material and environmental parameters. The test results show that the chloride diffusion coefficient increases as w/c increases, and chloride diffusion velocity decreases as penetration depth increases. It is found that the probability of corrosion initiation considering spatial variability is 13.1-18.5% greater than that without consideration of spatial variability. This indicates that neglecting spatial variations in evaluating probability of corrosion initiation time overestimates the structural reliability. It is also found that the probability of corrosion initiation for future climate change is 9-11% higher than that obtained from constant temperature. The mean value of T-CI based on a time-dependent chloride diffusion coefficient is 16.7% less than that obtained for a constant chloride diffusion coefficient. This suggests that it is more appropriate if penetration depth and w/c is considered when determining the time-dependent chloride diffusion coefficient.
语种：
英文
展开
Experimental Study on Mechanical Performance of U-Shaped Steel-Encased Concrete Composite Beam-Girder Joints
作者：
Hu, Zhangqi;He, Ran;Wang, Yukui;Lv, Weirong;Li, Jingchao
期刊：
Advances in Civil Engineering ,2021年2021 ISSN：1687-8086
通讯作者：
Hu, Z.
作者机构：
[Li, Jingchao; He, Ran; Wang, Yukui; Hu, Zhangqi] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Li, Jingchao; He, Ran; Wang, Yukui; Hu, Zhangqi] Hunan City Univ, Key Lab Key Technol Digital Urban Rural Spatial P, Yiyang 413000, Peoples R China.;[Lv, Weirong] Hunan Univ Sci & Technol, Coll Civil Engn, Xiangtan 411201, Peoples R China.
通讯机构：
[Hu, Z.] C;College of Civil Engineering, China
摘要：
This paper proposes a novel U-shaped steel-encased concrete composite beam-girder joint (referred to herein as the novel composite beam-girder joint), in which the U-shaped beams at two sides (L and R) are inserted into a shaped sleeve, and the U-shaped girder and two U-shaped beams are connected by the shaped sleeve through welding. Compared with the traditional beam-girder joints, the novel composite beam-girder joints take advantage of easy construction, light weight, and short construction period. The failure patterns, load-strain and load-deflection curves, and strain distributions of the novel composite beam-girder joints were investigated through the static loading tests on two full-scale specimens, denoted as GBJ1 and GBJ2. The two specimens were varied in beam section reinforcements. Specimen GBJ2 was equipped with 3φ16 additional bars in the U-shaped beams based on Specimen GBJ1. Test results show that the two specimens failed as the through arc cracks developed at the concrete slab interfaces. The additional bars can increase the bearing capacity slightly but will also increase the stress concentration on the bottom flange of the shaped sleeve, leading to the decrease of ductility for Specimen GBJ2. The slab effect is considered in the test and can thus reflect the actual stress state of the beam-girder joints well. This study can provide a reference for the design and application of beam-girder joints. © 2021 Zhangqi Hu et al.
语种：
英文
展开
Lightweight topology optimization with consideration of the fail-safe design principle for continuum structures
作者：
Peng, Xirong;Sui, Yunkang*
期刊：
Engineering Optimization ,2021年53(1):32-48 ISSN：0305-215X
通讯作者：
Sui, Yunkang
作者机构：
[Peng, Xirong] Hunan City Univ, Sch Civil Engn, Yiyang, Peoples R China.;[Sui, Yunkang] Beijing Univ Technol, Numer Simulat Ctr Engn, Beijing, Peoples R China.
通讯机构：
[Sui, Yunkang] B;Beijing Univ Technol, Numer Simulat Ctr Engn, Beijing, Peoples R China.
关键词：
Continuum structures;topology optimization;fail-safe
摘要：
The topology optimization of continuum structures is investigated to obtain an optimized topology satisfying the fail-safe design principle with suitable redundancy components. An optimization model with a nonlinear objective and linear constraints is established by defining the reciprocal topology variable as design variables and linearly approximating the structural performance. The model is solved by a dual sequential quadratic programming (DSQP) algorithm. Topology optimization with displacement constraints is used as an example. The presented optimization model and solution approach offers the following advantages. (1) A volume constraint, which makes determining reasonable values difficult, need not be specified. (2) Weighted coefficients, which combine multiple compliances under different load cases into a combined compliance, need not be specified as well. (3) The presented optimization model is a type of single-objective programming and thus avoids the challenges in the min-max model. (4) The proposed method shows a strong capability of finding optimum solutions. © 2019 Informa UK Limited, trading as Taylor & Francis Group.
语种：
英文
展开
A new empirical model for residual flexural capacity of corroded post-tensioned prestressed concrete beams
作者：
Lu, Zhao-Hui;Zhou, Qi-Hao;Li, Hai* ;Zhao, Yan-Gang
期刊：
Structures ,2021年34:4308-4321 ISSN：2352-0124
通讯作者：
Li, Hai
作者机构：
[Lu, Zhao-Hui; Zhou, Qi-Hao; Zhao, Yan-Gang] Beijing Univ Technol, Minist Educ, Key Lab Urban Secur & Disaster Engn, 100 Pingleyuan, Beijing 100124, Peoples R China.;[Lu, Zhao-Hui] Cent South Univ, Natl Engn Lab High Speed Railway Construct, 22 Shaoshannan Rd, Changsha 410075, Peoples R China.;[Li, Hai] Hunan City Univ, Coll Civil Engn, 158 Yinbindong Rd, Yiyang 413049, Peoples R China.
通讯机构：
[Li, Hai] H;Hunan City Univ, Coll Civil Engn, 158 Yinbindong Rd, Yiyang 413049, Peoples R China.
关键词：
Post-tensioned prestressed concrete beams;Corrosion;Flexural capacity;Databank;Empirical models
摘要：
In this paper, a total of 70 experimental flexural tests of corroded post-tensioned prestressed concrete (PC) beams were gathered from the published literatures. Using the experimental data, a comprehensive databank of flexural capacity of the corroded PC beams was established. Meanwhile, four existing empirical models for calculating the residual flexural strength of the corroded PC beams were also gleaned and contrasted with each other based on the databank. It turns out that three of the four existing empirical models underestimate the flexural capacity. To deeply analyze the factors affecting the flexural capacity, numerous factors were discussed, e.g., the corrosion ratio, beam width, effective height of the beam section, concrete compressive strength, and the ratio of strength between the tensile reinforcement (including prestressed and non-prestressed reinforcement) and concrete. It is found that the corroded post-tensioned PC beams’ residual flexural capacity is affected most by the corrosion ratio. In the end, a better empirical model is proposed for computing the residual flexural capacity of corroded PC beams, which provides accurate and effective predictions in a wide range of corrosion ratio for engineering practice.
语种：
英文
展开
Joint Optimization of Running Route and Scheduling for the Mixed Demand Responsive Feeder Transit with Time-Dependent Travel Times
作者：
Wang, Zhengwu;Yu, Jie;Hao, Wei;Xiang, Jian
期刊：
IEEE Transactions on Intelligent Transportation Systems ,2021年22(4):2498-2509 ISSN：1524-9050
通讯作者：
Yu, J.;Hao, W.
作者机构：
[Xiang, Jian; Hao, Wei; Wang, Zhengwu; Yu, Jie] Changsha Univ Sci & Technol, Sch Traff & Transportat Engn, Changsha 410114, Peoples R China.;[Yu, Jie] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.
通讯机构：
[Hao, W.] S;[Yu, J.] C;School of Traffic and Transportation Engineering, China;College of Civil Engineering, China
关键词：
Real-time systems;Optimization;Roads;Vehicle dynamics;Dynamic scheduling;Urban areas;Vehicle routing;Mixed demand;responsive feeder transit;time-dependent road network;two-stage method
摘要：
As an emerging urban public transport mode, responsive feeder transit system is flexible and can offer door-to-door services between new districts at margins with low urban transit coverage and trunk bus station. In this study, a joint optimization of running route and scheduling for responsive feeder transit under mixed demand (i.e., reservation and real-time demands) of the time-dependent road network was investigated. A two-stage optimization method was designed together with considering the mixed demands. At the first stage, the initial running route and scheduling were determined according to all reservation demands. At the second stage, the running route and scheduling were continuously optimized based on the real-time demands. The real-time demand responsive strategy, which is built up by using quantitative batch treatment rather than immediate treatment and dynamic route updating strategy for global optimization, were designed by utilizing the submission order of real-time demands. A joint optimization model of running route and scheduling was constructed based on the quantitative batch decision points in the time-dependent road network together with combination of the actual road network. In this model, the minimum total system cost was used, which is composed of the vehicle running costs and passengers' traveling time costs with constraints including vehicle capacity, passengers' time window, and vehicle running time. A solving algorithm based on the adaptive genetic algorithm was designed by considering the characteristics of the joint optimization model.
语种：
英文
展开
Multi-objective optimisation of a graphite-slag conductive composite applying a BAS-SVR based model
作者：
Sun, Junbo;Wang, Xiangyu;Zhang, Junfei;Xiao, Fan;Sun, Yuantian;...
期刊：
Journal of Building Engineering ,2021年44:103223 ISSN：2352-7102
通讯作者：
Xiangyu Wang<&wdkj&>Yufei Wang
作者机构：
[Sun, Junbo] Chongqing Univ, Lndustrial Technol Res Lnstitute, Chongqing 400045, Peoples R China.;[Sun, Junbo] Chongqing Univ, Chongqing Univ Liyang, Inst Smart City, Liyang 213300, Jiangsu, Peoples R China.;[Wang, Yufei; Wang, Xiangyu] Curtin Univ, Sch Design & Built Environm, Perth, WA 6102, Australia.;[Zhang, Junfei] Hebei Univ Technol, Sch Civil & Transportat Engn, 5340 Xiping Rd, Tianjin 300401, Peoples R China.;[Xiao, Fan] Zhongkai Univ Agr & Engn, Coll Management, Guangzhou 510225, Peoples R China.
通讯机构：
[Xiangyu Wang; Yufei Wang] S;School of Design and Built Environment, Curtin University, Perth, WA, 6102, Australia
关键词：
Multi-objective optimisation;Graphite;Waste slag;Mechanical strength;Electrical resistivity
摘要：
Electrically conductive cementitious composites (ECCC) possesses numerous virtues including low resistivity and high strain sensitivity, which can be applied as a conductive sensor to monitor structural health. This study produced ECCC with three conductive ingredients, consisting of graphite powder (GP), ground granulated blast-furnace slag (GGBS), and steel slag (SS). The uniaxial compressive strength (UCS), flexural strength (FS), and electrical conductivity were investigated, which showed that the GP enhanced the conductivity more remarkably than the other conductive materials. However, it simultaneously reduced the UCS and FS of ECCC. Also, ECCC samples containing SS had higher FS and conductivity than that containing GGBS. To overcome the challenge of excessive variables, this study introduced an artificial-intelligence (AI) based multi-objective optimisation (MOO) model with 252 samples for the FS test and 336 samples for the resistivity experiment. The support vector regression (SVR) was trained with hyperparameters tuned by the beetle antennae search (BAS). The high correlation coefficients (0.981) were achieved on both test sets. The BAS-SVR model acted as the objective function to develop the multi-objective beetle antennae search algorithm (MOBAS-SVR). The Pareto front of a tri-objective mixture optimisation design for ECCC (cost, FS, and resistivity) was successfully obtained as a design reference. Furthermore, sensitivity research was implemented to comprehend the importance of the variables for the FS and electrical resistivity.
语种：
英文
展开
