Applied Mechanics Reviews最新文献_第9页

Thermomechanical Constitutive Models of Shape Memory Polymers and Their Composites 形状记忆聚合物及其复合材料的热力学本构模型

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-11-08 DOI: 10.1115/1.4056131

Wei Zhao, Liwu Liu, X. Lan, J. Leng, Yanju Liu

引用次数: 5

What Is the Internal Pressure That Initiates Damage in Cementitious Materials during Freezing and Thawing? A Micromechanical Analysis 在冻融过程中引起胶凝材料损伤的内部压力是什么?微观力学分析

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-11-05 DOI: 10.3390/applmech3040074

J. Timothy, Alexander Haynack, T. Kränkel, C. Gehlen

{"title":"What Is the Internal Pressure That Initiates Damage in Cementitious Materials during Freezing and Thawing? A Micromechanical Analysis","authors":"J. Timothy, Alexander Haynack, T. Kränkel, C. Gehlen","doi":"10.3390/applmech3040074","DOIUrl":"https://doi.org/10.3390/applmech3040074","url":null,"abstract":"Damage induced by repetitive freezing and thawing processes is one of the critical factors that affect concrete durability in cold climates. This deterioration process manifests as surface scaling and internal damage. The damage processes are governed by physicochemical mechanisms that are active across multiple scales. In this contribution, we present a novel multiscale theoretical framework for estimating the critical pressure required for microcrack initiation during freezing and thawing of cementitious mortar. Continuum micromechanics and fracture mechanics is used to model the phenomena of microcrack initiation and growth. Damage at the microscale is upscaled to the level of the specimen using multilevel homogenization. The critical pressure is estimated using poromechanics at the microscopic scale. A theoretical analysis shows that in the frozen state, the material can resist higher pressures. As a consequence, the material is more susceptible to damage during thawing. The micromechanical predictions are within the range of the predictions obtained by electrokinetic theory.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80385100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Local Stability in the Process of Excavation Located in High Permeability Saturated Sand of Diaphragm Wall Construction 高渗透饱和砂土连续墙开挖过程中的局部稳定性研究

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-31 DOI: 10.3390/applmech3040072

Yuhang Liu, Linchun Wei, Yanfei Zhu, X. Zhuang

{"title":"Local Stability in the Process of Excavation Located in High Permeability Saturated Sand of Diaphragm Wall Construction","authors":"Yuhang Liu, Linchun Wei, Yanfei Zhu, X. Zhuang","doi":"10.3390/applmech3040072","DOIUrl":"https://doi.org/10.3390/applmech3040072","url":null,"abstract":"The stability of the slurry trench is very important in the construction of the underground diaphragm wall. In the current research, the local instability of the slurry trench is mainly investigated after the excavation of a unit slot is completely completed. However, the local stability in the process of excavation has received little attention. In this paper, the local stability in the process of excavation located in high permeability strata of diaphragm wall construction is investigated. A slurry infiltration experiment was carried out to investigate the distribution of the excess pore pressure in the high permeability strata, which can determine the effective support pressure. Then, the local stability of the slurry trench in the process of excavation located in high permeability saturated sand is calculated. The results show that the same types of sand according to the design code cannot be simply treated to have the same permeability and similar distribution of the excess pore pressure, since whether the filter cake can be formed and the quality of the filter cake are the key factors to determine the distribution of the excess pore pressure. This is also crucial for the local stability in the process of excavation located in high permeability saturated sand. It is suggested that attention should be paid to the local stability in the process of excavation located in high permeability strata when the slurry infiltration mode is the pure permeable zone.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77597107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stiction and Friction of Nano- and Microtextured Liquid Silicon Rubber Surface Formed by Injection Molding 注射成型液态硅橡胶纳米和微织构表面的粘滞和摩擦

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-31 DOI: 10.3390/applmech3040073

C. Koplin, Dennis F. Weißer, A. Fromm, M. Deckert

{"title":"Stiction and Friction of Nano- and Microtextured Liquid Silicon Rubber Surface Formed by Injection Molding","authors":"C. Koplin, Dennis F. Weißer, A. Fromm, M. Deckert","doi":"10.3390/applmech3040073","DOIUrl":"https://doi.org/10.3390/applmech3040073","url":null,"abstract":"The use of cross-linking polymers such as liquid silicone rubber (LSR) can replicate serviceable surfaces with nano- and microstructures via the injection molding process. Laser ablation can be used to introduce microstructures into molding tools, while nanostructures are generated via PVD coating processes on the tools. This is why nanostructures are built using self-organized layer growth. The aim of this study was to generate evidence of direction-dependent coefficients of friction of elastomeric surfaces in dry or lubricated contact in boundary friction. Models of the dry friction of elastomeric surfaces, such as Schallamach waves or stick-slip cycles, were used to describe the friction modulation of such surfaces. Assumptions for model contacts against smooth partners, both dry and with lubrication, as well as assumptions for the interaction of structures with smooth surfaces, were investigated. It was found that for elastomer surfaces with Shore hardness 50, nanostructures are suitable for creating a direction-dependent friction increase in static and sliding friction. Friction reductions with defined microstructures are possible if their periodicity seems to interact with the wavelength of possible Schallamach waves. The choice of lubrication determines the forced wetting of the contact, but due to the structuring, there is a continuous transition to mixed friction.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80493411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Shear Band Control for Improved Strength-Ductility Synergy in Metallic Glasses 提高金属玻璃强度-延性协同效应的剪切带控制

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-18 DOI: 10.1115/1.4056010

Z. Sha, Y. Teng, L. H. Poh, T. Wang, Huajian Gao

引用次数: 7

Design and Fabrication of Untethered Light-Actuated Microbots in Fluid for Biomedical Applications 生物医学流体中无系留光驱动微型机器人的设计与制造

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-17 DOI: 10.3390/applmech3040071

Md. Faiyaz Jamil, Mishal Pokharel, Kihan Park

{"title":"Design and Fabrication of Untethered Light-Actuated Microbots in Fluid for Biomedical Applications","authors":"Md. Faiyaz Jamil, Mishal Pokharel, Kihan Park","doi":"10.3390/applmech3040071","DOIUrl":"https://doi.org/10.3390/applmech3040071","url":null,"abstract":"Untethered mobile robots at the micro-scale have the ability to improve biomedical research by performing specialized tasks inside complex physiological environments. Light-controlled wireless microbots are becoming the center of interest thanks to their accuracy in navigation and potential to carry out operations in a non-invasive manner inside living environments. The pioneering light-engineered microbots are currently in the early stage of animal trials. There is a long way ahead before they can be employed in humans for therapeutic applications such as targeted drug delivery, cancer cell diagnosis, tissue engineering, etc. The design of light-actuated microbots is one of the challenging parts along with the biocompatibility and precision control for in vivo applications. Recent progress in light-activated microbots has revealed a few innovative design concepts. In this study, we presented a framework on the different aspects with a comparative analysis of potential designs for the next generation of light-controlled microbots. Utilizing numerical simulations of fluid-structure interactions, limiting design elements of the microbots are addressed. We envision that this study will eventually facilitate the integration of robotic applications into the real world owing to the described design considerations.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83537897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Undamped Free Vibration Analysis of Functionally Graded Beams: A Dynamic Finite Element Approach 功能梯度梁无阻尼自由振动分析:一种动力有限元方法

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-07 DOI: 10.3390/applmech3040070

A. Gee, S. M. Hashemi

引用次数: 1

A Review of Techniques for Measuring the Biot Coefficient and Other Effective Stress Parameters for Fluid-Saturated Rocks 饱和流体岩石Biot系数及其他有效应力参数测量技术综述

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-07 DOI: 10.1115/1.4055888

H. Kasani, A. Selvadurai

{"title":"A Review of Techniques for Measuring the Biot Coefficient and Other Effective Stress Parameters for Fluid-Saturated Rocks","authors":"H. Kasani, A. Selvadurai","doi":"10.1115/1.4055888","DOIUrl":"https://doi.org/10.1115/1.4055888","url":null,"abstract":"\u0000 Predicting the behavior of a saturated rock with variations in pore fluid pressure during geo-energy production and storage, deep geological disposal of nuclear wastes, etc. is carried out using the isothermal theory of poroelasticity that incorporates Biot's effective stress principle. Several experimental methods for determining Biot's effective stress parameter have been documented in the literature. The original definition of Biot's effective stress is constantly being extended to account for non-linear and inelastic behavior of the rock. The objective of this study is to review the fundamentals of the original experimental approach for determining Biot's coefficient and other developments, their advantages and disadvantages, and include several case studies. Current techniques are based on different premises: jacketed and unjacketed bulk moduli or compressibility values; volume changes of the bulk and pore fluid from a drained triaxial test on a saturated sample; isotropic-isochoric compression tests on a saturated sample; matching volumetric strains or failure envelopes for dry and saturated samples; variations of rock properties, such as volumetric strain, permeability, compressional and shear wave velocities, with respect to confining stress and pore pressure; estimation of the Biot coefficient from other poroelastic parameters; and approximation of the dry bulk modulus or unjacketed bulk modulus of the rock from mineralogical compositions or ultrasonic wave velocities. This article discusses variations in Biot's effective stress coefficients produced using the different techniques and how factors such as pore geometry, test conditions, stress path, and test temperature affect the Biot's coefficient.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87334262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

A Novel Technique for Temporarily Repair and Improvement of Damaged Pin Joint Support Bores 一种临时修复和改进损伤销钉连接支撑孔的新技术

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-06 DOI: 10.3390/applmech3040069

Ø. Karlsen, H. Lemu, I. Berkani

{"title":"A Novel Technique for Temporarily Repair and Improvement of Damaged Pin Joint Support Bores","authors":"Ø. Karlsen, H. Lemu, I. Berkani","doi":"10.3390/applmech3040069","DOIUrl":"https://doi.org/10.3390/applmech3040069","url":null,"abstract":"Damaged support bores due to wear and ovality can be critical for a machine and its operation, in addition to representing a safety problem and risk of pin breakage. It can be a costly operation to perform the required repairs in between planned service periods, especially because of the unplanned down time. A joint with a standard cylindrical pin will often experience wear and ovality in the support bore surfaces, and at some point, repairs will have to be performed. This study investigates and compares five options when a joint with a cylindrical pin has reached a severe level of wear and ovality, outside its planned service stop. The work involved testing the viability of 3D scanning of the damaged bore surface, 3D printing of a metal bushing, and inserting the bushing into the damaged joint. In addition, two pin solutions, i.e., a standard cylindrical pin and an expanding pin type, were installed into the repaired joint, loaded, and the strain on the pin ends close to the supports was measured. For the sake of comparison, the supports had both smooth circular bore and severe wear and ovality. It was concluded that it is possible to produce and install the 3D-printed bushing insert without major problems; the insert had satisfactory capability during test loading, and it most probably represents a good solution when it comes to the reduction in unwanted downtime during unplanned repairs of damaged joints.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77926557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application-Oriented Digital Image Correlation for the High-Speed Deformation and Fracture Analysis of AISI 1045 and Ti6Al4V Materials 面向应用的数字图像相关技术在AISI 1045和Ti6Al4V材料高速变形和断裂分析中的应用

IF 14.3 1区工程技术

Applied Mechanics Reviews Pub Date : 2022-10-05 DOI: 10.3390/applmech3040068

L. Gerdes, S. Berger, J. Saelzer, Pascal Franck, Ramon Helwing, A. Zabel, F. Walther

{"title":"Application-Oriented Digital Image Correlation for the High-Speed Deformation and Fracture Analysis of AISI 1045 and Ti6Al4V Materials","authors":"L. Gerdes, S. Berger, J. Saelzer, Pascal Franck, Ramon Helwing, A. Zabel, F. Walther","doi":"10.3390/applmech3040068","DOIUrl":"https://doi.org/10.3390/applmech3040068","url":null,"abstract":"In order to achieve realistic simulations of the chip formation, high quality input data regarding the flow stress and damage behavior of the materials are required. The split Hopkinson pressure bar (SHPB) test setup for the characterization of highly dynamic material properties offers a suitable method for generating high strain rates, similar to those in the chip formation zone. However, the strain measurement in SHPB is usually performed by means of strain gauges. This leads to an unreliable evaluation of strain rate and flow stress/shear flow stress in the case of an inhomogeneous material deformation, since this method presents the total strain whilst excluding local deformations. Inhomogeneous deformations are induced deliberately in special shear specimens, as they are also observed in the investigated cylindrical specimens. The present work deals with this issue by providing two additional measurement techniques, which are applied in SHPB tests for cylindrical specimens made of AISI 1045 and Ti6Al4V. To enable a local strain resolution, digital image correlation (DIC) is applied to high-speed images of the deformation process. In order to allow for the detection of shear bands in the specimens, a deep-learning-based approach is presented. The two measurement methods (strain gauges and DIC) are compared and discussed. In particular, the findings regarding the inhomogeneous deformation of Ti6Al4V allow for future improvements in the result quality of SHPB tests. The presented algorithm shows promising predictions for shear band detection and creates the basis for an automated evaluation of shear sample results, as well as an AI-based pre-selection of frames for the DIC evaluation of SHPB tests.","PeriodicalId":8048,"journal":{"name":"Applied Mechanics Reviews","volume":null,"pages":null},"PeriodicalIF":14.3,"publicationDate":"2022-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84133572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1