Powder Technology最新文献_第3页

Evaluating the limitations of gradient boosting and SHAP in predicting magnetite separation performance in PLIMS 评估梯度助推和SHAP在预测PLIMS磁铁矿分离性能方面的局限性

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-01-02 DOI: 10.1016/j.powtec.2025.122108

Arif Mustafa, Yoshiyasu Takefuji

引用次数: 0

Numerical simulation of non-spherical particulate matter (PM) dynamics in tangential-inlet cyclones 切向进口旋风管内非球形颗粒物动力学的数值模拟

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-01-02 DOI: 10.1016/j.powtec.2026.122113

Kamel Abdelazim Elshorbagy, Elhussien Abdelmoneam Mohammed, Mohamed G. AbdElKader

This study examines the influence of particle sphericity on the aerodynamic behavior and separation efficiency of gas–solid cyclone separators using computational fluid dynamics, focusing on particles in the PM₁₀ range and smaller. A steady-state Reynolds Stress Model (RSM) was applied to resolve anisotropic turbulence and capture the swirling flow inside the cyclone. Simulations were performed under one-way and two-way coupling across particle densities of 700–3320 kg/m³ and sphericity values of 0.5–1.0, representing components from light organic aerosols to dense mineral dusts.

Results show that sphericity markedly impacts particle–flow interactions. Spherical particles promote tighter vortex cores and more predictable centrifugal motion, whereas non-spherical particles increase turbulence and re-entrainment. Pressure drop was influenced more by flow distortion and wall interactions than particle shape alone. Separation efficiency decreased by up to 4.8 % when particle shape was considered, especially at higher densities and near-spherical forms. Accounting for sphericity also reduced the overestimation of pressure drop common in spherical approximations by 4.5–7.3 %.

The RSM framework provided consistent predictions of mean flow fields and particle dynamics, confirming its suitability for cyclone design with lower computational cost. By explicitly considering particle shape, this study offers new insights for optimizing cyclone performance in particulate matter (PM) control, particularly for fine particles within the PM₁₀ threshold. These findings support the design of more energy-efficient and effective separation systems for environmental, industrial, and filtration applications.

本研究利用计算流体动力学研究了颗粒球形度对气固旋风分离器气动性能和分离效率的影响，重点研究了PM₁₀范围内及更小的颗粒。采用稳态雷诺应力模型（RSM）求解各向异性湍流并捕捉旋流器内部的旋流。在颗粒密度为700-3320 kg/m3，球度值为0.5-1.0的单向和双向耦合条件下进行了模拟，代表了从轻有机气溶胶到致密矿物粉尘的成分。结果表明，球度对颗粒流相互作用有显著影响。球形颗粒促进更紧密的漩涡核心和更可预测的离心运动，而非球形颗粒增加湍流和再夹带。压降受流动畸变和壁面相互作用的影响大于颗粒形状的影响。当考虑颗粒形状时，分离效率下降了4.8%，特别是在高密度和接近球形的情况下。考虑球形度也减少了对球形近似中常见的压降的高估4.5 - 7.3%。RSM框架提供了一致的平均流场和颗粒动力学预测，证实了其具有较低计算成本的旋风分离器设计适用性。通过明确考虑颗粒形状，本研究为优化颗粒物质（PM）控制中的旋风性能提供了新的见解，特别是对于PM 1 0阈值内的细颗粒。这些发现支持为环境、工业和过滤应用设计更节能、更有效的分离系统。

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引用次数: 0

Cohesion characterization and collapse behavior of wet granular mixtures with density heterogeneity 具有密度非均质性的湿颗粒混合物的黏聚特性及坍塌行为

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-01-02 DOI: 10.1016/j.powtec.2025.122109

Yuantao Zhang, Yisong Wu, Yuecheng Wang, Dengming Wang

This study investigates the collapse dynamics and mechanical stability of low-saturation wet granular columns composed of particles with different densities. A discrete element method (DEM), validated against experimental measurements, is employed to systematically examine the effects of particle density ratios and compositional proportions on flow behavior, deposit morphology, and capillary-induced cohesion. To characterize cohesion in density-bidisperse systems, an equivalent Bond number

{B_{O}}^{*}

is introduced by accounting for the probability-weighted contributions of liquid-bridge formation between particle pairs. This parameter provides a unified measure of bulk cohesion and governs the transition between block-like and continuous collapse regimes, enabling the construction of a predictive collapse phase diagram. At the macroscopic scale, a dimensionless cohesion parameter

ξ^{*}

, defined as the ratio of cohesive to gravitational stresses using the effective mixture mass density, is incorporated into a Mohr-Coulomb failure criterion to evaluate column stability across different initial configurations. The combined use of the probability-weighted

{B_{O}}^{*}

and the stress-ratio-based

ξ^{*}

provide a physically grounded framework for predicting the collapse dynamics and mechanical stability of low-saturation wet granular materials in both geophysical and industrial contexts.

研究了由不同密度颗粒组成的低饱和度湿颗粒柱的崩塌动力学和力学稳定性。采用离散元法（DEM）对实验测量进行验证，系统地研究了颗粒密度比和成分比例对流动行为、沉积物形态和毛细血管诱导内聚的影响。为了描述密度-双分散系统中的内聚，通过计算粒子对之间液桥形成的概率加权贡献，引入了等效键数BO *。该参数提供了块体内聚力的统一度量，并控制块状和连续崩溃状态之间的过渡，从而能够构建预测崩溃相图。在宏观尺度上，一个无因次黏聚参数ξ∗，定义为使用有效混合物质量密度的黏聚与重力应力之比，被纳入Mohr-Coulomb破坏准则，以评估不同初始配置的柱稳定性。结合使用概率加权BO *和基于应力比的ξ *为预测低饱和度湿颗粒材料在地球物理和工业背景下的崩塌动力学和机械稳定性提供了一个物理基础框架。

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引用次数: 0

Permeability enhancement in coal under surfactant-modified alkaline hydrophobic SiO2 nanofluid treatment 表面活性剂改性碱性疏水性SiO2纳米流体处理下煤的渗透性增强

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-31 DOI: 10.1016/j.powtec.2025.122100

Fangzheng Ma , Fei Huang , Yu Zhang , Yafei Luo , Pengfei Wang , He Li , Lei Liu

The predominance of micropores in low-permeability coal seams inherently restricts water injection due to capillary effects, impeding permeability enhancement. An advanced anionic surfactant and alkaline hydrophobic SiO₂ (AS-AH SiO₂) nanofluid was developed to reduce pore resistance, change the dominant pore type and increase coal sample porosity. Seepage experiments were performed on coal samples treated with AS-AH SiO₂ nanofluids at varying mass concentrations. Nuclear Magnetic Resonance (NMR) and contact angle measurements were used to assess coal wettability and liquid-phase retention removal. Fourier-transform infrared (FTIR) spectroscopy was employed to investigate changes in oxygen-containing/hydroxyl functional groups. Low-temperature liquid nitrogen adsorption experiments analyzed porosity, while scanning electron microscopy (SEM) observed structural alterations. Results indicate that permeabilities of all nanofluid-treated coal samples increased, reaching a stable value within the 0.1–0.15 % mass concentration range. Contact angles on coal surfaces rose from <90° (raw coal) to >90° (AS-AH SiO₂-treated), while oxygen-containing/hydroxyl functional groups decreased, collectively indicating a transition from hydrophilic to hydrophobic surfaces. This finding was corroborated by NMR results, revealing substantial liquid release from mesopores in treated samples. Porosity analyses via Barrett-Joyner-Halenda (BJH) and Brunauer-Emmett-Teller (BET) methods demonstrated increased pore volumes and specific surface areas in treated coal. Furthermore, density functional theory (DFT) analysis demonstrated a transition in the dominant pore size distribution of coal samples, evolving from micropore-dominated to mesopore-dominated systems. SEM imaging revealed fragmentation of raw coal blocks into smaller particles, generating extensive mesopores. In summary, AS-AH SiO₂ nanofluids could effectively reduce pore resistance and enhance coal porosity optimally at 0.1–0.15 % mass concentration. These findings present a novel material for permeability enhancement during coalbed liquid injection.

低渗透煤层中微孔的优势，由于毛细效应固有地限制了注水，阻碍了渗透率的提高。研制了一种新型阴离子表面活性剂和碱性疏水性SiO2 （AS-AH SiO2）纳米流体，以降低孔隙阻力，改变主要孔隙类型，提高煤样孔隙度。采用不同质量浓度的AS-AH - SiO2纳米流体对煤样进行了渗流实验。核磁共振（NMR）和接触角测量用于评估煤的润湿性和液相保留去除。傅里叶变换红外光谱（FTIR）研究了含氧/羟基官能团的变化。低温液氮吸附实验分析孔隙度，扫描电镜（SEM）观察结构变化。结果表明，经过纳米流体处理的煤样渗透率均有所提高，在0.1 ~ 0.15%的质量浓度范围内达到稳定值。煤表面的接触角从<；90°（原煤）上升到>；90°（AS-AH - sio2处理），而含氧/羟基官能团减少，共同表明从亲水表面到疏水表面的转变。核磁共振结果证实了这一发现，揭示了处理样品中介孔的大量液体释放。通过Barrett-Joyner-Halenda （BJH）和brunauer - emmet - teller （BET）方法进行的孔隙度分析表明，处理后的煤孔隙体积和比表面积增加。此外，密度泛函理论（DFT）分析表明，煤样的主要孔径分布发生了从微孔为主向中孔为主的转变。扫描电镜成像显示原煤块破碎成更小的颗粒，产生广泛的介孔。综上所述，在质量浓度为0.1 ~ 0.15%时，AS-AH SiO2纳米流体可以有效降低孔隙阻力，提高煤的孔隙度。这些发现为煤层注液增渗提供了一种新的材料。

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引用次数: 0

A weighted Monte Carlo method for modeling aggregation breakage phenomena: Application to Al2O3 nanoparticle aggregates 一种加权蒙特卡罗方法模拟团聚体破碎现象：应用于氧化铝纳米颗粒团聚体

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-31 DOI: 10.1016/j.powtec.2025.122110

Abhilekha Baid , Kavita Ola , Stutee Bhoi , Jitendra Kumar , Evangelos Tsotsas

Simulating aggregation and breakage is challenging for broad particle size distributions with sparsely populated large-size classes. We develop a novel Weighted Monte Carlo (WMC) algorithm to simulate aggregation and breakage processes. This method offers significant advantages over the conventional Constant Number Monte Carlo (CNMC) algorithm, particularly in its ability to accurately capture size distributions and effectively represent particles that are fewer in number but larger in size. The algorithm’s effectiveness has been validated through case studies involving breakage, aggregation, and their combination, demonstrating strong agreement with exact results. In the heavy-tailed test case for breakage, WMC reproduces both the volume distribution and the moments obtained from the Weighted Finite Volume Method, while CNMC shows clear deviations in the moments due to under-representation of the tail. Additionally, the new algorithm has been successfully applied to simulate the aggregation and breakage of nanoparticle aggregates in a spouted bed with a broad initial size distribution, accurately resolving the tail of the particle size spectrum. WMC also significantly reduces computational time, requiring 17 s compared to 5 h for CNMC in pure breakage, 28 s compared to 2 h in the heavy tailed breakage case and 208 s compared to 19 h for CNMC in pure aggregation, and 3 h in the experimental case where CNMC is not computationally feasible.

模拟聚集和破碎是具有挑战性的广泛的粒度分布和稀疏分布的大尺寸类。我们开发了一种新的加权蒙特卡罗（WMC）算法来模拟聚集和破碎过程。与传统的常数蒙特卡罗（CNMC）算法相比，该方法具有显著的优势，特别是它能够准确地捕获尺寸分布，并有效地表示数量较少但尺寸较大的颗粒。该算法的有效性已通过涉及断裂、聚合和它们的组合的案例研究得到验证，显示出与精确结果的强烈一致性。在断裂的重尾测试用例中，WMC再现了体积分布和从加权有限体积法获得的矩，而CNMC由于尾的代表性不足，在矩上显示出明显的偏差。此外，该算法还成功地模拟了初始粒径分布较宽的喷淋床中纳米颗粒聚集体的聚集和破碎过程，准确地解析了粒径谱的尾部。WMC还显著减少了计算时间，纯断裂情况下CNMC需要17秒，而CNMC需要5小时，重尾断裂情况下需要28秒，纯聚集情况下需要208秒，而CNMC在计算上不可行的实验情况下需要3小时。

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引用次数: 0

A computational framework for modeling the interaction between flexible multibody systems and non-spherical particles 柔性多体系统与非球形粒子相互作用的计算框架

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-31 DOI: 10.1016/j.powtec.2025.122104

Bo Lei , Hanyu Lin , Ming Zhang , Jinyang Liu

Simulating the interactions between flexible structures and non-spherical granular media is a critical challenge in engineering, characterized by strong nonlinearities, large deformations, and complex contact mechanics. This study proposes an efficient computational framework for the coupled dynamics of flexible shell systems and non-spherical granular media. Flexible structures are modeled using the absolute nodal coordinate formulation (ANCF) to capture large deformations and geometric nonlinearities, while non-spherical particles are represented by superquadrics to describe complex grain shapes. In addition, a novel contact detection algorithm for shell-superquadric interactions is developed, and a heterogeneous CPU–GPU parallel computing strategy is employed to enhance computational efficiency in large-scale simulations. The effectiveness of the proposed framework is validated through a series of numerical examples. Furthermore, simulations of granular flows with particles of different shapes impacting a flexible baffle further demonstrate the capability of the method in addressing coupled dynamics between non-spherical granular materials and flexible systems.

模拟柔性结构与非球形颗粒介质之间的相互作用是工程中的一个关键挑战，其特点是强非线性、大变形和复杂的接触力学。本研究提出了柔性壳系统与非球形颗粒介质耦合动力学的有效计算框架。柔性结构的建模采用绝对节点坐标法（ANCF）来捕捉大变形和几何非线性，而非球形颗粒则采用超二次曲面来描述复杂的晶粒形状。此外，提出了一种新的壳-超二次相互作用接触检测算法，并采用异构CPU-GPU并行计算策略提高了大规模仿真的计算效率。通过一系列数值算例验证了该框架的有效性。此外，不同形状颗粒撞击柔性折流板的颗粒流模拟进一步证明了该方法在解决非球形颗粒材料与柔性系统之间耦合动力学问题方面的能力。

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引用次数: 0

DEM simulation of the magnetic-aligned compaction process of NdFeB particles and the effect of magnetic field strength 钕铁硼颗粒磁排列压实过程的DEM模拟及磁场强度的影响

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-31 DOI: 10.1016/j.powtec.2025.122107

Qinglang Zhou , Xiaodong Xing , Shuyong Jiang , Nan Dong

A discrete element method (DEM) model combining magnetic dipole interactions with the Edinburgh Elastoplastic Adhesion (EEPA) contact model under double-action pressing is developed to investigate magnetic-aligned compaction of NdFeB particles and the influence of magnetic field strength on particle alignment. Under a magnetic field strength of 1.8 T, the simulations show that particles in the alignment stage rapidly rotate to align their easy magnetization axes with the magnetic field, where the average alignment degree is enhanced from 48.35 % to 99.27 %. During subsequent compaction, enhanced contact forces and relative motion disturb this aligned state, slightly reducing the average alignment degree to 96.48 %. Meanwhile, simulations of the sensitivity of particle alignment to friction coefficient show that when the wall friction coefficient is raised from 0.1 to 0.4, the average alignment degree is reduced from 97.1 % to 96.0 %. Furthermore, a systematic analysis demonstrates that increasing the magnetic field strength significantly improves particle alignment in the alignment stage and enhances resistance to alignment disruption during compaction. For example, when the magnetic field strength is enhanced from 0.25 to 2.0 T, the average alignment degree of the green compact rises from 82.68 % to 96.84 %. Experimental results confirm the accuracy of the simulations in terms of capturing particle alignment behavior and the effect of magnetic field strength on alignment degree, showing strong agreement with experimental observations.

建立了双作用压合条件下磁偶极子相互作用与爱丁堡弹塑性粘接（EEPA）接触模型相结合的离散元法（DEM）模型，研究了钕铁硼粒子的磁排列压合以及磁场强度对粒子排列的影响。模拟结果表明，在1.8 T磁场强度下，粒子在对准阶段快速旋转，易磁化轴与磁场对齐，平均对准度由48.35%提高到99.27%。在随后的压实过程中，增强的接触力和相对运动扰乱了这种对齐状态，使平均对齐度略微降低至96.48%。同时，模拟颗粒对摩擦系数的敏感性表明，当壁面摩擦系数从0.1提高到0.4时，颗粒的平均排列度从97.1%降低到96.0%。此外，系统分析表明，增加磁场强度可以显著改善颗粒在排列阶段的排列，并增强压实过程中对排列破坏的抵抗力。例如，当磁场强度从0.25 T增强到2.0 T时，绿色致密体的平均对准度从82.68%提高到96.84%。实验结果证实了模拟在捕获粒子排列行为和磁场强度对排列程度的影响方面的准确性，与实验观察结果有较强的一致性。

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引用次数: 0

Quantitative evaluation of transient pressure fluctuation behavior in jump tests applied to pharmaceutical powder materials 药用粉剂跳变试验中瞬态压力波动行为的定量评价

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-30 DOI: 10.1016/j.powtec.2025.122105

Yusuke Imayoshi , Shuji Ohsaki , Hideya Nakamura , Satoru Watano , Pierre Tchoreloff , Vincent Mazel

Strain-rate sensitivity in certain metallic materials results from the interplay between two opposing mechanisms: positive strain-rate sensitivity (PSRS), wherein resistance to deformation increases with the strain rate, and negative strain-rate sensitivity (NSRS), which is associated with dynamic strain aging. In our previous study, jump tests on pharmaceutical powders revealed stress transients indicative of NSRS by Desbois et al. (2022) [1]. However, these observations were limited to few powders, and the underlying causes of the transient behavior were not fully explained. Building on these findings, we conducted jump tests on multiple exhibiting a range of viscoplastic behaviors. During the tests, both die wall and punch pressures were simultaneously measured to evaluate the von Mises and hydrostatic stresses. Pronounced transient fluctuations were observed in the von Mises stress, particularly for strongly viscoplastic powder materials. The results indicated contributions from the NSRS and suggested the involvement of a deviatoric stress component. To interpret the transients observed during the jump tests, we applied the two-factor framework proposed by Kaneko and Oyamada (2000) for metals. Furthermore, a two-factor constitutive model was developed representing PSRS- and NSRS-driven responses to quantitatively assess the balance between the PSRS and NSRS. The model reproduced both the magnitude and timescale of the fluctuations across different materials. Collectively, the results demonstrated that the interplay between the PSRS and NSRS governs the complex stress evolution observed in the jump tests, underscoring that the strain-rate sensitivity of powder materials results from the relationship between the PSRS and NSRS.

某些金属材料的应变率敏感性是由两种相反机制的相互作用产生的：正应变率敏感性（PSRS）和负应变率敏感性（NSRS），前者的变形抗力随应变率的增加而增加，后者与动态应变老化有关。在我们之前的研究中，Desbois等人（2022）对药物粉末进行跳跃测试，发现应力瞬态表明NSRS。然而，这些观察仅限于少数粉末，并没有完全解释瞬态行为的根本原因。在这些发现的基础上，我们对多种表现出粘塑性行为的材料进行了跳跃测试。在试验过程中，同时测量了模壁和凸模压力，以评估von Mises应力和静水应力。在von Mises应力中观察到明显的瞬态波动，特别是对于强粘塑性粉末材料。结果表明了NSRS的贡献，并表明偏差应力成分的参与。为了解释跳跃试验中观察到的瞬态，我们采用了Kaneko和yamada（2000）提出的金属双因素框架。此外，我们还建立了一个代表PSRS和NSRS驱动响应的双因子本构模型，以定量评估PSRS和NSRS之间的平衡。该模型再现了不同材料之间波动的幅度和时间尺度。综上所述，结果表明PSRS和NSRS之间的相互作用支配着跳跃试验中观察到的复杂应力演化，强调粉末材料的应变率敏感性是PSRS和NSRS之间的关系造成的。

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引用次数: 0

Particle dynamic characteristics in swirling flow pneumatic conveying system with the variable-pitch blade based on CWT and DMD 基于CWT和DMD的变桨叶旋流气力输送系统颗粒动态特性

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-30 DOI: 10.1016/j.powtec.2025.122106

Mengfei Zhang , Fei Yan , Bo Song , Zhiyin Yang , Rui Zhu , Jian Zhang

To elucidate the energy-saving mechanism of a swirling flow pneumatic conveying system with variable-pitch blades, this study combines continuous wavelet transform (CWT) and dynamic mode decomposition (DMD) to analyze particle dynamic characteristics from multiple scales. Firstly, the energy-saving performance of variable-pitch blades is evaluated in terms of system pressure drop and power consumption coefficient. Compared to conventional axial flow, the variable-pitch blades reduce the optimal conveying velocity and power consumption coefficient by up to 20.12 % and 15.52 %, respectively. Subsequently, the particle concentration and velocity distributions are measured using electrical capacitance tomography (ECT) and particle image velocimetry (PIV), confirming that the variable-pitch blades significantly enhance particle suspension and dispersion in the pipe. Finally, CWT and DMD are employed to conduct a multi-scale analysis of the particle dynamics. The CWT analysis indicates that the variable-pitch blades promote large-scale particle motion while suppressing small-scale motion near the inlet; as the conveying distance increases, particle motion shifts toward smaller scales. The DMD results further support this trend, showing that the blades augment low-frequency modal energy while suppressing high-frequency energy in the upstream region. The analyses of DMD fluctuation intensity, vorticity, and Reynolds shear stress confirm that the variable-pitch blades promote a more uniform particle distribution.

为了阐明变桨叶旋流气力输送系统的节能机理，本研究将连续小波变换（CWT）和动态模态分解（DMD）相结合，从多尺度分析颗粒的动态特性。首先，从系统压降和能耗系数两个方面对变桨叶的节能性能进行了评价。与常规轴流相比，变桨距叶片可将最佳输送速度和功率消耗系数分别降低20.12%和15.52%。随后，利用电容层析成像（ECT）和粒子图像测速（PIV）测量了颗粒浓度和速度分布，证实了变桨叶显著增强了颗粒在管道中的悬浮和分散。最后，利用CWT和DMD对颗粒动力学进行多尺度分析。CWT分析表明，变桨叶促进了颗粒的大尺度运动，抑制了入口附近的小尺度运动；随着输送距离的增加，颗粒运动向更小的尺度移动。DMD结果进一步支持了这一趋势，表明叶片增加了低频模态能量，同时抑制了上游区域的高频能量。对DMD波动强度、涡度和雷诺剪切应力的分析证实，变桨距叶片使颗粒分布更加均匀。

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引用次数: 0

Bearing and deformation behavior of geogrid-encased recycled aggregate columns: Coupled effects of filler characteristics and geogrid interaction 土工格栅包裹再生骨料柱的承载和变形行为：填料特性和土工格栅相互作用的耦合影响

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2025-12-29 DOI: 10.1016/j.powtec.2025.122099

Ling Zhang , Jing-Peng Tan , Xiao-Cong Cai , Mei-Xiang Gu , Yun-Hao Chen

In response to the substantial global increase in construction and demolition (C&D) waste generation, geogrid-encased recycled aggregate columns (GERACs) demonstrate promising potential in soft soil foundation treatment. A total of 27 GERACs were tested under unconfined compression. The effects of aggregate gradation, relative density, and geogrid strength on bearing capacity and deformation behavior were systematically examined. PIV (Particle Image Velocimetry) aptured the radial deformation process, while aggregate-geogrid interface interactions were documented. The results indicate that the uniformly graded fine aggregate (UF) columns exhibit low porosity and weak interlocking with the geogrid, resulting in superior bearing and deformation performance, achieving the highest ultimate bearing capacity of 1014 kPa and the lowest maximum radial swelling of 2.03. In contrast, columns with uniformly graded coarse aggregates (UC) and well-graded continuous aggregates (WC) form a coarse-grained skeleton that enhances stress transmission, increasing the load transfer coefficient to 0.77 and 0.83, respectively, compared to 0.72 for UF columns. However, the UC column exhibits the lowest bearing capacity (890 kPa) and tends to experience greater non-uniform radial swelling (reaching 2.56 %) due to the pronounced interlocking between coarse aggregates and geogrid, which may induce local geogrid tensile failure and trigger shear failure of the column. Increasing the relative density of the fill material effectively improves both column strength and load transfer performance but also intensifies radial expansion. In such cases, employing a higher-strength geogrid mitigates non-uniform swelling, enhances column stability, and ultimately leads to a bulging failure mode.

为了应对全球建筑和拆除（C&；D）废物产生的大量增加，土工格栅包覆再生骨料柱（GERACs）在软土地基处理中显示出巨大的潜力。在无侧限压缩条件下对27个gerac进行了试验。系统地研究了骨料级配、相对密度和土工格栅强度对承载力和变形行为的影响。PIV（粒子图像测速）捕获了径向变形过程，同时记录了聚集体-土工格栅界面的相互作用。结果表明：均匀级配细骨料柱孔隙率低，与土工格栅互锁较弱，具有较好的承载和变形性能，最高极限承载力为1014 kPa，最大径向膨胀最小为2.03；相比之下，具有均匀级配粗骨料（UC）和分级良好的连续骨料（WC）的柱形成粗粒度骨架，增强了应力传递，将荷载传递系数分别提高到0.77和0.83，而UF柱的荷载传递系数为0.72。粗集料与土工格栅之间存在明显的联系性，导致粗集料与土工格栅之间存在较大的非均匀径向膨胀（达2.56%），可能诱发土工格栅局部拉伸破坏，并引发柱的剪切破坏，混凝土柱的承载力最低（890 kPa）。增加填料的相对密度可以有效地提高柱的强度和荷载传递性能，但也会加剧柱的径向膨胀。在这种情况下，采用高强度土工格栅可以减轻非均匀膨胀，提高柱的稳定性，最终导致胀形破坏模式。

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引用次数: 0