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Characterization of load-bearing and failure properties of fractured rock masses reinforced by negative pressure grouting

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Journal of Rock Mechanics and Geotechnical Engineering 2025年

作者： Fang, Juejing Yang, Ke Aslani, Farhad Lyu, Xin He, Xiang Li, Guiquan Zhang, Jiqiang Key Laboratory of Provincial and Ministry of Education for Safe and Efficient Mining of Coal Mines Anhui University of Science and Technology Huainan 232001 China Materials and Structures Innovation Group School of Engineering The University of Western Australia Perth 6009 WA Australia School of Engineering Edith Cowan University Perth 6027 WA Australia Hefei Design and Research Institute of Coal Industry Co. Ltd. Hefei 340041 China

Grouting injection is a vital technique for addressing the challenges of high stress and significant deformation in the surrounding rock during deep mining operations, playing a crucial role in promoting green and low-carbon extraction methodologies. In this study, grouting reinforcement processes were examined by conducting grouting experiments on a fractured rock with varying negative pressures (0–100 kPa), followed by uniaxial compression testing of the grout-reinforced bodies. This investigation explored the diffusion patterns of grout under negative pressure and established a constitutive model of damage-bearing capacity for bodies reinforced by negative pressure grouting. It further studied the enhancement effect of negative pressure on the load-bearing capacity of the reinforced bodies and analyzed the instability mechanism of damage and failure in these bodies. The results indicated that the diffusion of grout under negative pressure is influenced by four types of forces, which alter the extent of grout diffusion within the fractured rock mass. Introducing a damage constitutive model that serially connects pore and framework elements characterizes the damage and failure behavior of grout-reinforced bodies under different negative pressures. As the negative pressure increases, changes in porosity, water-to-cement ratio, and admixture quantity occur in the grout-reinforced specimens, with the strength mean curve showing a trend of first increasing and then decreasing, reaching a threshold at a negative pressure of 60 kPa. With increasing negative pressure, the negative pressure damage variable decreases and then increases, and the stronger the interfacial microelement connections caused by the negative pressure, the greater the bearing capacity, ultimately manifesting in different failure modes. © 2025 Institute of Rock and Soil Mechanics, Chinese Academy of sciences

关键词： Constitutive model Grout reinforcement Mechanical properties

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Effect of processing and microstructural properties of chickpea-flours on in vitro digestion and appetite sensations

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Food Research International 2022年第0期157卷 111245页

作者： Pälchen, Katharina Bredie, Wender L.P. Duijsens, Dorine Isaac Alfie Castillo, Alan Hendrickx, Marc Van Loey, Ann Raben, Anne Grauwet, Tara Laboratory of Food Technology Kasteelpark Arenberg 22 PB 2457 Leuven3001 Belgium Department of Food Science Section for Food Design and Consumer Behaviour Faculty of Science University of Copenhagen Rolighedsvej 26 FrederiksbergDK-1958 Denmark Department of Nutrition Exercise and Sports Faculty of Science University of Copenhagen Rolighedsvej 30 FrederiksbergDK-1958 Denmark Clinical Research Copenhagen University Hospital - Steno Diabetes Center Copenhagen HerlevDK-2730 Denmark

Nowadays, pulse flours are ingredients that are more and more used as substitutes in traditional staples (i.e., pasta, bread). In this study, cellular chickpea-flour was used as an ingredient to replace conventional raw-milled chickpea-flour in suspensions and semi-solid purees. The contribution of cellular integrity on in vitro macronutrient digestion and the subsequent effect on in vivo appetite sensations were investigated. Alternating the flour preparation sequence by interchanging hydrothermal treatment and mechanical disintegration (thermo-mechanical treatment) resulted in three chickpea-flours with distinct levels of cellular integrity, and thus nutrient accessibility. The study showed that cellular integrity in chickpea-flours was preserved upon secondary hydrothermal treatment and led to significant attenuation of in vitro macronutrient digestion as compared to conventional chickpea-flour. In a randomized crossover design, significant increase of mean in vivo subjective appetite sensations satiety and fullness along with decreases in hunger, desire to eat, and prospective food consumption were achieved when cellular integrity was kept without an effect on palatability and appearance of the purees (n = 22). In vitro digestion along with microstructural assessment confirmed the importance of cellular integrity for attenuating macronutrient digestion and thereby contributing to enhanced subjective satiety and fullness in pulses. Overall, this study highlights the promising potential of altarenating the flour preparation sequence resulting in macronutrient and energy-matched flours with different nutrient encapsulation which lead to different in vitro digestion kinetics and in vivo appetite sensations. © 2022 Elsevier Ltd

关键词： Disintegration

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IMPROVING NAVIGATION ANALYSIS WITH OD-D: THE VISUALLY INTERACTIVE ORBIT DETERMINATION DASHBOARD

IMPROVING NAVIGATION ANALYSIS WITH OD-D: THE VISUALLY INTERA...

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AAS/AIAA Astrodynamics Specialist Conference, 2020

作者： Crowley, James Mackey, Isaac Stuart, Jeffrey Ramaswamy, Basak Alper Jah, Moriba Aerospace Engineering and Engineering Mechanics The University of Texas at Austin 110 Inner Campus Dr AustinTX78705 United States Computer Science University of California Santa Barbara 2104 Harold Frank Hall Santa BarbaraCA93106 United States Mission Design & Navigation Section Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. PasadenaCA91109 United States Planning & Execution Systems Section Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. PasadenaCA91109 United States

ISBN: (纸本)9780877036753

Robust orbit determination requires iterative multiple hypothesis analysis with the goal of using evidence to infer the most plausible states and model parameters regarding the behavior of an anthropogenic space object (a.k.a. a spacecraft) as possible, a process that can be both time and labor intensive. To increase the efficiency and accuracy of this analysis, we provide an analytic application capable of comprehensively and concurrently displaying multiple orbit determination solutions, leveraging contemporary data visualization techniques. This work details the design and visualization decisions made in the creation of the "Orbit Determination Dashboard," a tool aimed at giving users an interactive work-space for understanding how changes to input parameters defining the space environment, spacecraft features, sensor models and more affect their orbit determination solutions. © 2021, Univelt Inc. All rights reserved.

关键词： Data visualization

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Frontispiz: Simultaneously Strengthening and Toughening All-Natural Structural Materials via 3D Nanofiber Network Interfacial design

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Angewandte Chemie 2024年第48期136卷

作者： Dr. Huai-Bin Yang Xiang Zhao Quan Wang Yu-Hong Ruan Zhao-Xiang Liu Xin Yue Dr. Yin Bo Zhu Prof. Heng An Wu Dr. Qing-Fang Guan Prof. Shu-Hong Yu Department of Chemistry New Cornerstone Science Laboratory Institute of Biomimetic Materials & Chemistry Anhui Engineering Laboratory of Biomimetic Materials Division of Nanomaterials & Chemistry Hefei National Research Center for Physical Sciences at the Microscale. University of Science and Technology of China Hefei 230026 China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China Institute of Innovative Materials (I2 M) Department of Materials Science and Engineering Department of Chemistry Southern University of Science and Technology. Shenzhen 518055 China

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Active learning with multifidelity modeling for efficient rare event simulation

arXiv

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arXiv 2021年

作者： Dhulipala, Somayajulu L.N. Shields, Michael D. Spencer, Benjamin W. Bolisetti, Chandrakanth Slaughter, Andrew E. Labouré, Vincent M. Chakroborty, Promit Computational Mechanics and Materials Idaho National Laboratory Idaho FallsID83402 United States Department of Civil and Systems Engineering Johns Hopkins University BaltimoreMD21218 United States Advanced Reactor Technology and Design Idaho National Laboratory Idaho FallsID83402 United States Computational Frameworks Idaho National Laboratory Idaho FallsID83402 United States Reactor Physics Methods and Analysis Idaho National Laboratory Idaho FallsID83402 United States

While multifidelity modeling provides a cost-effective way to conduct uncertainty quantification with computationally expensive models, much greater efficiency can be achieved by adaptively deciding the number of required high-fidelity (HF) simulations, depending on the type and complexity of the problem and the desired accuracy in the results. We propose a framework for active learning with multifidelity modeling emphasizing the efficient estimation of rare events. Our framework works by fusing a low-fidelity (LF) prediction with an HF-inferred correction, filtering the corrected LF prediction to decide whether to call the high-fidelity model, and for enhanced subsequent accuracy, adapting the correction for the LF prediction after every HF model call. The framework does not make any assumptions as to the LF model type or its correlations with the HF model. In addition, for improved robustness when estimating smaller failure probabilities, we propose using dynamic active learning functions that decide when to call the HF model. We demonstrate our framework using several academic case studies and two finite element (FE) model case studies: estimating Navier-Stokes velocities using the Stokes approximation and estimating stresses in a transversely isotropic model subjected to displacements via a coarsely meshed isotropic model. Across these case studies, not only did the proposed framework estimate the failure probabilities accurately, but compared with either Monte Carlo or a standard variance reduction method, it also required only a small fraction of the calls to the HF model. © 2021, CC BY-NC-ND.

关键词： Uncertainty analysis

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laboratory Investigation of the Warm-Mixed Recycled technology Influence on the Improvement of Aged Sbs Modified Asphalt Content

SSRN

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SSRN 2022年

作者： Qiu, Ke Li, Bo Li, Xiaomin Chen, Jiangcai Zhang, Yan Li, Andi Li, Zhiwei National and Provincial Joint Engineering Laboratory of Road & Bridge Disaster Prevention and Control Lanzhou Jiaotong University Lanzhou730070 China Gansu Province Transportation Planning Survey & Design Institute CO. LTD Lanzhou730030 China School of Transportation Science and Engineering Harbin Institute of Technology Harbin150001 China Guangxi beitou transportation maintenance technology group CO. LTD Nanning530299 China

Warm mix recycled technology has been proven to improve RAP content, but how to comprehensively and quantitatively describe the improvement effect has not yet been a better way. This paper aims to establish a method to quantitatively evaluate the impact of warm mix recycled technology on aged SBS modified asphalt (SBSMA) content. The regenerated SBSMA with and without regeneration agents, and warm mix recycled SBSMA, which all contained different aged SBSMA percentages (20%, 40%, 60%, 100%), were prepared in the laboratory. Brookfield viscosity tests, Dynamic shear rheological tests, and Force-ductility tests were taken to evaluate the effect of different aged SBSMA percentages on viscosity-temperature performance, rutting resistance, fatigue resistance, and low temperature cracking. Viscosity, high temperature, medium temperature and low temperature indicators were selected as criteria and the importance of different indicators was given according to various climate zones. The weights of different indicators were calculated using analysis hierarchical process and the improvement value of warm mix recycled technology on aged SBSMA content was given. The results illustrated that regenerated technology could increase the content of aged SBSMA by about 30%, and warm mix recycled technology could increase about 50%, which were calculated from the analytic hierarchy process. The increase of aged SBSMA content varied with the change in ambient temperature. The high-temperature performance of regenerated asphalt was weakened, but the low-temperature performance was increased when the regeneration agent was presented in. The fatigue performance of the regenerated asphalt with regeneration agent reached the peak value when the content of aged SBSMA was 40%. The wax-based warm additive played a major role in increasing high-temperature and fatigue performance, but it was unfavorable to low-temperature performance. © 2022, The Authors. All rights reserved.

关键词： Temperature

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Typicality of nonequilibrium (quasi-)steady currents

arXiv

引用

arXiv 2021年

作者： Xu, Xiansong Guo, Chu Poletti, Dario Science Mathematics and Technology Cluster Singapore University of Technology and Design 8 Somapah Road 487372 Singapore Henan Key Laboratory of Quantum Information and Cryptography Henan Zhengzhou450000 China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control Ministry of Education Department of Physics Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Changsha410081 China EPD Pillar Singapore University of Technology and Design 8 Somapah Road 487372 Singapore

The understanding of the emergence of equilibrium statistical mechanics has progressed significantly thanks to developments from typicality, canonical and dynamical, and from the eigenstate thermalization hypothesis. Here we focus on a nonequilibrium scenario in which two nonintegrable systems prepared in different states are locally and non-extensively coupled to each other. Using both perturbative analysis and numerical exact simulations of up to 28 spin systems, we demonstrate the typical emergence of nonequilibrium (quasi-)steady current for weak coupling between the subsystems. We also identify that these currents originate from a prethermalization mechanism, which is the weak and local breaking of the conservation of the energy for each subsystem. © 2021, CC BY.

关键词： Statistical mechanics

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Frontispiece: Simultaneously Strengthening and Toughening All-Natural Structural Materials via 3D Nanofiber Network Interfacial design

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Angewandte Chemie International Edition 2024年第48期63卷

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Fatigue life prediction of composite laminates based on energy conservation and damage entropy accumulation

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International Journal of Fatigue 2025年 199卷

作者： Han, Yalin Wu, Fuqiang Lian, Yuhao Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics Nanjing210016 China National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics Nanjing210016 China

Fatigue is an irreversible thermodynamic process accompanied by multi-component energy dissipation and entropy accumulation. This study analyzes the energy composition of total mechanical input hysteresis energy during the fatigue process of composites. By excluding thermal dissipation and viscoelastic internal friction dissipation energy, which do not directly contribute to fatigue damage, the irrecoverable damage energy is extracted. This portion of energy is closely related to the final failure of the specimen and the accumulation of damage entropy. The differences in energy dissipation mechanisms between low-cycle and high-cycle fatigue are evaluated, and a fatigue life prediction model for composites is established based on different damage entropy thresholds. Fatigue tests were conducted on glass fiber-reinforced polymer (GFRP) composite laminates, and the fatigue properties were investigated using infrared thermography (IRT) and digital image correlation (DIC). The proposed damage entropy model for fatigue life prediction was validated at various loading frequencies (2–5 Hz) and across a wide range of cycles (102-106 cycles), showing good agreement with the experimental results. © 2025 Elsevier Ltd

关键词： Polymer matrix composites

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Uncovering the Iceberg in the Sea: Fundamentals of Pulse Shaping and Modulation design for Random ISAC Signals

arXiv

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arXiv 2025年

作者： Liu, Fan Xiong, Yifeng Lu, Shihang Li, Shuangyang Yuan, Weijie Masouros, Christos Jin, Shi Caire, Giuseppe The National Mobile Communications Research Laboratory Southeast University Nanjing210096 China The School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen518055 China The School of Information and Electronic Engineering Beijing University of Posts and Telecommunications Beijing100876 China The Chair of Communications and Information Theory Technical University of Berlin Berlin10623 Germany The Department of Electrical and Electronic Engineering University College London LondonWC1E 7JE United Kingdom

Integrated Sensing and Communications (ISAC) is expected to play a pivotal role in future 6G networks. To maximize time-frequency resource utilization, 6G ISAC systems must exploit data payload signals, that are inherently random, for both communication and sensing tasks. This paper provides a comprehensive analysis of the sensing performance of such communication-centric ISAC signals, with a focus on modulation and pulse shaping design to reshape the statistical properties of their auto-correlation functions (ACFs), thereby improving the target ranging performance. We derive a closed-form expression for the expectation of the squared ACF of random ISAC signals, considering arbitrary modulation bases and constellation mappings within the Nyquist pulse shaping framework. The structure is metaphorically described as an "iceberg hidden in the sea", where the "iceberg" represents the squared mean of the ACF of random ISAC signals, that is determined by the pulse shaping filter, and the "sea level" characterizes the corresponding variance, caused by the randomness of the data payload. Our analysis shows that, for QAM/PSK constellations with Nyquist pulse shaping, Orthogonal Frequency Division Multiplexing (OFDM) achieves the lowest ranging sidelobe level across all lags. Building on these insights, we propose a novel Nyquist pulse shaping design to enhance the sensing performance of random ISAC signals. Numerical results validate our theoretical findings, showing that the proposed pulse shaping significantly reduces ranging sidelobes compared to conventional root-raised cosine (RRC) pulse shaping, thereby improving the ranging performance. Copyright © 2025, The Authors. All rights reserved.

关键词： Orthogonal frequency division multiplexing

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