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螺栓钢板连接预制混凝土轴压性能及承载力计算公式

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工程科学与技术 2025年第1期57卷 167-176页

作者：杨延婷葛琪左文豪李国熊峰吕洋孟永杰刘鹏宋瑛涵四川大学建筑与环境学院四川成都610065 中建三局第一建设工程有限责任公司湖北武汉430000

预制混凝土墙板结合夹心保温技术可大幅提升墙体的保温隔热性,提高建造速度和节能效率。本文设计了螺栓钢板拼接预制混凝土夹心墙板试件,开展试件的轴向压力荷载试验,研究其轴压性能,提出了考虑螺栓钢板拼接影响下的墙板轴心受压极限承... 详细信息

预制混凝土墙板结合夹心保温技术可大幅提升墙体的保温隔热性,提高建造速度和节能效率。本文设计了螺栓钢板拼接预制混凝土夹心墙板试件,开展试件的轴向压力荷载试验,研究其轴压性能,提出了考虑螺栓钢板拼接影响下的墙板轴心受压极限承载力计算公式。试验结果表明:夹心墙板破坏模式主要为螺栓钢板节点上方以及墙趾两端混凝土的压溃,混凝土面板与夹心保温层在墙体底部轻微分层,墙体侧面出现较大竖向裂缝。将试件的试验轴向荷载承载力与本文提出的公式及现有的公式进行了对比,结果表明:国内现有公式计算值与试验值的差值百分比为5%,国外现有计算公式与试验值的差值百分比为45.7%~77.2%,然而本文提出的公式与试验值差值百分比仅为0.4%。国外现有的公式非常保守,本文提出的公式能够准确预测此种螺栓连接墙板的轴向承载力。在试验研究基础上,考虑了长细比、墙体厚度、连接件布置、混凝土边肋等参数,进一步建立有限元模型验证本文提出的公式。分析结果表明:数值模型的计算结果与本文提出的计算公式误差在–8.05%~2.65%之内,国内现有公式和国外现有公式与计算值误差分别在–2.25%~8.58%和41.61%~78.41%范围内,本文公式预测结果较为准确。最后,分析了各个参数对螺栓钢板拼接预制混凝土夹心墙板轴向承载能力的影响,发现墙板的配筋率对极限承载力无明显影响;合理布置GFRP连接件、设置竖向混凝土肋、减小墙板长细比和增加混凝土板厚度可以提高墙体承载性能。

关键词：预制混凝土夹心墙体螺栓钢板连接轴压性能有限元分析承载力计算公式

Data-augmented landslide displacement prediction using generative adversarial network

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Journal of Rock Mechanics and geotechnical Engineering 2024年第10期16卷 4017-4033页

作者： qi ge Jin Li Suzanne Lacasse Hongyue Sun Zhongqiang Liu College of Civil Engineering Nanjing Forestry UniversityNanjingChina Institute of Artificial Intelligence Nanjing University of Information Science and TechnologyNanjingChina Department of Natural Hazards Norwegian Geotechnical InstituteOsloNorway Ocean College Zhejiang UniversityHangzhouChina

Landslides are destructive natural disasters that cause catastrophic damage and loss of life *** predicting landslide displacement enables effective early warning and risk ***,the limited availability of on-site measurement data has been a substantial obstacle in developing data-driven models,such as state-of-the-art machine learning(ML)*** address these challenges,this study proposes a data augmentation framework that uses generative adversarial networks(GANs),a recent advance in generative artificial intelligence(AI),to improve the accuracy of landslide displacement *** framework provides effective data augmentation to enhance limited datasets.A recurrent GAN model,RGAN-LS,is proposed,specifically designed to generate realistic synthetic multivariate time series that mimics the characteristics of real landslide on-site measurement data.A customized moment-matching loss is incorporated in addition to the adversarial loss in GAN during the training of RGAN-LS to capture the temporal dynamics and correlations in real time series ***,the synthetic data generated by RGAN-LS is used to enhance the training of long short-term memory(LSTM)networks and particle swarm optimization-support vector machine(PSO-SVM)models for landslide displacement prediction *** on two landslides in the Three Gorges Reservoir(TGR)region show a significant improvement in LSTM model prediction performance when trained on augmented *** instance,in the case of the Baishuihe landslide,the average root mean square error(RMSE)increases by 16.11%,and the mean absolute error(MAE)by 17.59%.More importantly,the model’s responsiveness during mutational stages is enhanced for early warning ***,the results have shown that the static PSO-SVM model only sees marginal gains compared to recurrent models such as *** analysis indicates that an optimal synthetic-to-real data ratio(50%on the illustration cases)maximizes the

关键词： Machine learning(ML) Time series generative adversarial network(GAN) Three Gorges reservoir(TGR) Landslide displacement prediction

Broadband Insulator-Based Dynamic Diode with Ultrafast Hot Carriers Process

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Research 2023年第2期2022卷 297-304页

作者： Runjiang Shen Yanghua Lu Xutao Yu qi ge Huiming Zhong Shisheng Lin Colege of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Chongqing 2D Material Institute Chongqing 410020China Department Emergency The Seond Aliated Hopital Zhejiang Universy Shoolof Medicin Zhejiang Univery Hangzhou 310009China State Key Laboratory of Modern Optical Instrumentation Zhejiang UniversityHangzhou 310027China Hangzhou gelanfeng Technology Co.Ltd. Hangzhou 310051China

The excitation,rebound,and transport process of hot carriers(HCs)inside dynamic diode(DD)based on insulators has been rarely explored due to the original stereotyped in which it was thought that the insulators are ***,the carrier dynamics of DD is totally different from the static diode,which may bring a subverting insight of insulators.

关键词： diode insulator Broadband

Effect of Graphite Content and Granularity on Mechanical and Tribological Properties of Bronze Alloyed Powder Composite

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Journal of Iron and Steel Research International 2005年第1期12卷 54-57页

作者： DENG Chen-hong CHEN Guang-zhi ge qi-lu Central Iron and Steel Research Institute

The bronze alloyed powder composite containing nanoparticles was developed by hot *** effects of the content and granularity of graphite on hardness,machinability,bending strength,compression strength,and friction and wear behavior of the composites were *** microstructures of the specimens were analyzed by *** results showed that the graphites are distributed in net when nanographites are added,resulting in the decrease of mechanical properties and abrasive *** the content of nanographite is 10%,the composite is *** graphite is distributed in the form of block when micrographite is added,improving the mechanical properties and abrasive *** track was studied by SEM.

关键词： nanoparticle mechanical property friction wear abrasive resistance

Vibration Response and Stress Analysis of Planar Elastic Tube Bundle Induced by Fluid Flow

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 89-96页

作者： De-Rong Duan Pei-qi ge Wen-Bo Bi Yan-Ying Dong School of Mechanical Engineering Shandong University Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education Shandong University

Flow?induced vibration plays a positive role on heat transfer enhancement. Meanwhile, it is also a negative factor for fatigue strength. Satisfying the fatigue strength is the primary prerequisite for heat transfer enhancement. This paper numerically studied the flow?induced vibration of planar elastic tube bundle based on a two?way fluid–structure interaction(FSI) calculation. The numerical calculation involved the unsteady, three?dimensional incompressible governing equations solved with finite volume approach and the dynamic balance equation of planar elastic tube bundle solved with finite element method combined with dynamic mesh scheme. The numerical approach was verified by comparing with the published experimental results. Then the vibration trajectory, deformation and stress contour of planar elastic tube bundle were all studied. Results show that the combined movement of planar elastic tube bundle represents the agitation from inside to outside. The vibration of out?of?plane is the main vibration form with the typically sinusoidal behavior because the magnitude of displacement along the out?of?plane direction is the 100 times than the value of in?plane direction. The dangerous point locates in the innermost tube where the equivalent stress can be utilized to study the multiaxial fatigue of planar elastic tube bundle due to the alternating stress concentration. In the velocity range of 0.2-3 m/s, it is inferred that the vibration amplitude plays a role on the stress response and the stress amplitude is susceptible to the fluid velocity. This research paves a way for studying the fatigue strength of planar elastic tube bundle by flow?induced vibration.

关键词： Flow?induced vibration Planar elastic tube bundle Vibration response Stress analysis

Grinding exfoliation for scalable production of 2D materials

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National Science Review 2020年第3期7卷 559-560页

作者： Kostya S.Novoselov qi ge Daria V.ANDreeva Department of Materials Science and Engineering National University of Singapore National Graphene Institute University of Manchester

Over the past few years the utilisation of graphene in various areas of industry has strongly intensified [1]. Applications in thermal management, composite materials and energy consume an increasing amount of this tw... 详细信息

关键词： Grinding exfoliation for scalable production of 2D materials Graphene

Numerical analysis of shell-side flow-induced vibration of elastic tube bundle in heat exchanger

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Journal of Hydrodynamics 2018年第2期30卷 249-257页

作者： Jia-dong Ji Pei-qi ge Wen-bo Bi School of Mechanical Engineering Anhui University of Science and Technology Huainan 232001 China School of Mechanical Engineering Shandong University Jinan 250061 China

The responses of the flow-induced vibration of an elastic tube bundle subjected to the shell-side cross flow are investigated in this paper. The weak coupling method and the fluid solid interface are used to solve the fluid-structure interaction problem with consideration of the geometry and physical natures. The effects of the shell-side fluid flow velocity and the structural parameters on the flow-induced vibration are discussed. Numerical results demonstrate that the vibration frequency and amplitude at the monitor points increase with the increase of the shell-side water inlet velocity in all directions. The wall thickness and the external diameter of the elastic tube bundle have significant effects on the responses of the flow-induced vibration. The structural parameters affect the vibration frequency and amplitude, and the vibration equilibrium position in the water flow direction. The vibration frequency decreases with the increase of the tube external diameter. In addition, the vibration in the water flow direction has a lower equilibrium position when the elastic tube bundle has a larger wall thickness or smaller external diameter.

关键词： Flow-induced vibration heat exchanger elastic tube bundle fluid-structure interaction shell-side fluid weak coupling method

Modified commercial UV curable elastomers for passive 4D printing

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International Journal of Smart and Nano Materials 2019年第3期10卷 225-236页

作者： Hardik Hingorani Yuan-Fang Zhang Biao Zhang Ahmad Serjouei qi ge Digital Manufacturing and Design Centre Singapore University of Technology and DesignSingapore Science and Math Cluster Singapore University of Technology and DesignSingapore

Conventional 4D printing technologies are realized by combining 3D printing with soft active materials such as shape memory polymers(SMPs)and ***,the intrinsic material property limitations make the SMP or hydrogel-based 4D printing unsuitable to fabricate the actuators that need to exhibit fast-response,reversible ***,pneumatic actuations have been widely adopted by the soft robotics community to achieve fast-response,reversible actuations,and many efforts have been made to apply the pneumatic actuation to 3D printed structures to realize passive 4D printing with fast-response,reversible ***,the 3D printing of soft actuators/robots heavily relies on the commercially available UV curable elastomers the break strains of which are not sufficient for certain applications which require larger elastic *** this paper,we present two simple approaches to tune the mechanical properties such as stretchability,stiffness,and durability of the commercially available UV curable elastomers by adding:(i)mono-acrylate based linear chain builder;(ii)urethane diacrylate-based *** property characterizations have been performed to investigate the effects of adding the two additives on the stretchability,stiffness,mechanical repeatability as well as *** of fully printed robotic finger,grippers,and highly deformable 3D lattice structure are also presented.

关键词： 4D printing elastomer highly stretchable soft robots

Stiffness-Tunable Origami Structures via Multimaterial Three-Dimensional Printing

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Acta Mechanica Solida Sinica 2023年第4期36卷 582-593页

作者： qingjiang Liu Haitao Ye Jianxiang Cheng Honggeng Li Xiangnan He Bingcong Jian qi ge Shenzhen Key Laboratory of Soft Mechanics and Smart Manufacturing Southern University of Science and TechnologyShenzhen 518055China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055China

Origami structure has been employed in many engineering ***,there is currently no strategy that can systematically achieve stiffness-tunable origami(STO)structures through proper geometric ***,we report a strategy for designing and fabricating STO structures based on thick-panel origami using multimaterial 3D *** adjusting the soft hinge position,we tune the geometric parameterψto program the stiffness and strength of origami *** develop origami structures with graded stiffness and strength by stacking Kresling origami structures with differentψ.The printed structures show great cyclic characteristics and deformation *** optimizing combinations of structures with differentψ,the multi-layer Kresling STO structures can effectively reduce the peak impact,showing a good energy absorption *** proposed approach can be implemented in various origami patterns to design and tune the mechanical properties of origami structures for many potential applications.

关键词： Origami Multimaterial 3D printing Stiffness-tunable structure