Mechanics of Time-Dependent Materials最新文献_第2页

Tensile creep of Norway spruce on the tissue scale 挪威云杉组织尺度上的拉伸蠕变

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-03-20 DOI: 10.1007/s11043-025-09772-1

Alessia Ferrara, Falk K. Wittel

{"title":"Tensile creep of Norway spruce on the tissue scale","authors":"Alessia Ferrara, Falk K. Wittel","doi":"10.1007/s11043-025-09772-1","DOIUrl":"10.1007/s11043-025-09772-1","url":null,"abstract":"<div><p>The rheological behavior of wood emerges from complex mechanical interactions occurring across multiple length scales. This behavior is characterized by directional dependence, as well as sensitivity to moisture content, loading time, and the degree of loading. This study focuses on the viscoelastic creep response of Norway spruce (<i>Picea abies</i>) tissues under different moisture levels and loading degrees. Using a custom-designed, fully automated test rack with moisture control, we investigate the uniaxial, moisture-dependent creep compliances across all feasible anatomical directions, as well as of isolated earlywood (EW) and latewood (LW) slices to understand their contribution to the cumulative behavior of the growth ring. The creep response is compared to the moisture dependence of the elastic compliance, revealing nontrivial scaling behavior as a function of moisture content. The results show significant directional dependencies and reveal the critical impact of moisture on deformation mechanisms. The transverse directions involve a complex interaction between bending, determining a more compliant and moisture-sensitive creep response, and cell wall stretching in the softest direction compared to loading in grain. These findings offer valuable insights into the moisture-dependent creep mechanisms of wood slices, highlighting the importance of exploring different orientations and tissues at various moisture content to fully understand the creep behavior at the bulk scale.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11043-025-09772-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143668256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fractional-order energy equation of a fully wet longitudinal fin with convective–radiative heat exchange through Sumudu transform analysis 用苏木度变换分析全湿纵向翅片对流-辐射换热的分数阶能量方程

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-03-18 DOI: 10.1007/s11043-025-09773-0

Manohar R. Gombi, B. J. Gireesha, P. Venkatesh, M. L. Keerthi, G. K. Ramesh

{"title":"Fractional-order energy equation of a fully wet longitudinal fin with convective–radiative heat exchange through Sumudu transform analysis","authors":"Manohar R. Gombi, B. J. Gireesha, P. Venkatesh, M. L. Keerthi, G. K. Ramesh","doi":"10.1007/s11043-025-09773-0","DOIUrl":"10.1007/s11043-025-09773-0","url":null,"abstract":"<div><p>The Adomian Decomposition Sumudu Transform Method (ADSTM) is applied to solve a fractional-order problem that involves temperature variations in a fully wet convective–radiative longitudinal fin. Darcy’s law is used in formulating the energy balance equation to take into account the porous nature of the fin. The fractional-order energy balance equation for the fin is solved under two situations: a constant convective heat transfer coefficient and a temperature-dependent convective heat transfer coefficient. The ADSTM solution is compared with numerical results, obtained using the Runge–Kutta–Fehlberg approach. A series solution is obtained, and the roles of various parameters of the fractional-order differential equation are analyzed. It is found that the solution to the fractional-order differential equation outperforms the integer-order solution in modeling the temperature profile of the fin. Furthermore, it is observed that improvements in the wet porous characteristics of the fin lead to a reduction in its temperature.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on mechanisms of anchorage creep-induced prestress loss in prestressed systems with varying anchorage lengths 不同锚固长度预应力体系锚固蠕变引起预应力损失的机理研究

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-03-17 DOI: 10.1007/s11043-025-09774-z

Kai Yang, Jinchao Liu, Bo Wang, Dingwei Luo

{"title":"Study on mechanisms of anchorage creep-induced prestress loss in prestressed systems with varying anchorage lengths","authors":"Kai Yang, Jinchao Liu, Bo Wang, Dingwei Luo","doi":"10.1007/s11043-025-09774-z","DOIUrl":"10.1007/s11043-025-09774-z","url":null,"abstract":"<div><p>Prestress loss poses a significant risk to structural safety and must be carefully considered in the design of prestressed anchors. This study begins by analyzing the relationship between creep in the anchorage zone and prestress loss. Subsequently, creep tests were conducted to determine the creep parameters of the anchorage zone and the differences in creep behavior under varying anchorage lengths were compared. Based on the test results, numerical simulations were performed to investigate the evolution of mechanical behavior during prestress loss and the influence of anchorage length on long-term performance. The results indicated that the coupled process of prestress loss and creep could be characterized as creep behavior under variable load, where the load was correlated with the total displacement of the anchor. During prestress loss, the shear load distribution in the anchorage zone transitioned from a concentrated to a uniform pattern. Specifically, the shear load near the free section decreased while the shear load near the bottom increased. The boundary between these two regions remained relatively stable, ranging between 0.5 m and 0.75 m, regardless of anchorage length. Increasing the anchorage length significantly reduced the prestress loss during the first year. This reduction was attributed to the smaller shear force and creep deformation in the rear section, which constrained deformation in the front section and minimized retraction in the free section of the anchor. However, the effectiveness of increasing anchorage length diminished as the length continued to expand. These findings offer valuable insights into the influence of anchorage length on the long-term service capacity of prestressed anchors, guiding structural design and optimization.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tests of rubber properties under cyclical compression in determining indentation rolling resistance of conveyor belt 测定输送带压痕滚动阻力的循环压缩橡胶性能试验

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-03-12 DOI: 10.1007/s11043-025-09771-2

Dariusz Woźniak

{"title":"Tests of rubber properties under cyclical compression in determining indentation rolling resistance of conveyor belt","authors":"Dariusz Woźniak","doi":"10.1007/s11043-025-09771-2","DOIUrl":"10.1007/s11043-025-09771-2","url":null,"abstract":"<div><p>One of the most important ways to reduce energy consumption in belt conveyor transportation along horizontal routes of significant length is to ensure limited belt indentation rolling resistance. This type of resistance results from the cyclical compression of the bottom cover of the belt by idlers as the belt moves over successive idler sets. This paper presents a method for testing the dynamic properties of rubber subjected to cyclical compression. The presented analysis is multiaspect. The method parameters have been optimized to match one of the theoretical models of indentation rolling resistance calculations. The tests of dynamic properties were performed for five different rubber types and included calculations of the belt damping factor and modulus of elasticity. The theoretical model allowed for the calculations of belt indentation rolling resistance. The results were verified in indentation rolling resistance tests performed on a test rig designed for steel-cord belts. The measurements were performed for belt specimens with covers made of the tested rubber types. The calculation results highly correlated with the measurement results. The proposed method for testing the dynamic properties of rubber can not only provide data required in the calculations of the power demand from belt conveyors but also serve conveyor belt manufacturers in their search for rubber compounds used in belts that generate lower indentation rolling resistances.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143602254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Relaxation behavior of basalt fiber reinforced polymer bars under different environmental conditions 不同环境条件下玄武岩纤维增强聚合物棒的松弛行为

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-03-03 DOI: 10.1007/s11043-025-09765-0

Aly Hassan, Hesham Sokairge, Hany Elshafie

{"title":"Relaxation behavior of basalt fiber reinforced polymer bars under different environmental conditions","authors":"Aly Hassan, Hesham Sokairge, Hany Elshafie","doi":"10.1007/s11043-025-09765-0","DOIUrl":"10.1007/s11043-025-09765-0","url":null,"abstract":"<div><p>Relaxation behavior of fiber-reinforced polymer (FRP) bars is one of the main issues considered in prestressing applications. Recently, basalt FRP (BFRP) bars have been developed as an alternative to other types of FRP bars. However, the available studies on their relaxation behavior are still limited, especially under severe environmental conditions. In this study, the long-term relaxation behavior of BFRP bars was studied, the initial stress level under different environmental conditions are the variables considered in this investigation. A total of twenty-four specimens of BFRP bars of nominal diameter 6 mm were used in this study. The relaxation behavior and the residual tensile strength of BFRP after relaxation were experimentally assessed. The expected relaxation loss after a million hours was estimated based on the extrapolated statistical analysis of the experimental results. The test results showed that the relaxation behavior of BFRP bars under different initial stress levels have linear relationship with logarithm of time, similar to other types of FRP bars, and are significantly affected by the initial stress level. Furthermore, the test results demonstrated that the relaxation behavior of BFRP bars is slightly affected by seawater (pH 8.1) and can be recommended for use in marine structures. On the other hand, the test results showed that the acidic (5% HCl) and alkaline (10% NaOH) environmental conditions greatly impacted the relaxation behavior of BFRP bars, such that although BFRP bars stressed to 50% of their ultimate strength survived 1000 h under normal conditions, exposure to different environmental conditions resulted in their rupture under the same initial stress level. Finally, the expected million-hour relaxation losses of BFRP bars range between 7.76% and 13.75% under normal conditions based on the initial tensile stress level, while introducing seawater can increase this ratio to an average of 16.13%.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11043-025-09765-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of the tensile stress relaxation of biaxial warp-knitted fabrics regarding fabric interweaving structure 基于织物交织结构的双轴经编织物拉伸应力松弛评价

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-02-24 DOI: 10.1007/s11043-025-09769-w

Azita Asayesh, Masoome Ramezanzade Bidgoli

{"title":"Evaluation of the tensile stress relaxation of biaxial warp-knitted fabrics regarding fabric interweaving structure","authors":"Azita Asayesh, Masoome Ramezanzade Bidgoli","doi":"10.1007/s11043-025-09769-w","DOIUrl":"10.1007/s11043-025-09769-w","url":null,"abstract":"<div><p>Stress relaxation is a time-dependent mechanical behavior of textile materials, which can affect the performance of the fabrics in various applications, especially technical applications such as tensile structures, geotextiles, and medical textiles. The present study aims to consider the effect of fabric structure (Tricot, Locknit, Satin, Queen’s cord, Reverse Locknit, and Sharkskin) on the tensile stress relaxation of biaxial warp-knitted fabrics. According to the results, the fabric structure remarkably influences its stress relaxation. The stress relaxation of the fabric in the course direction increases by increasing the length of underlaps in the front and back guide bars. Using elastic yarns as weft yarns in the fabric structure reduces the stress relaxation of the fabric in the course direction without affecting the fabric’s stress relaxation in the wale direction. Finally, to improve the functionality of pressure garments under stress relaxation, using elastic weft yarns in the fabric structure and bounding the warp and weft yarns in the biaxial warp-knitted fabrics by the Tricot structure is proposed.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exact solution of channelized flow of MHD Maxwell fluid with suction/injection 吸/注MHD Maxwell流体通道化流动的精确解

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-02-20 DOI: 10.1007/s11043-025-09768-x

Ikhlaq Ahmad, Muhammad Waheed, Mushtaq Ahmad, Shajar Abbas, Abdullah Alhushaybari, Muyassar Norberdiyeva, Emad A Az-Zo’bi, Mohamad Ahmed Saleem AL-Khasawneh

引用次数: 0

Implementation of FEM and Taguchi analysis on blood flow for Casson fluid inclusion of di- and tri-Hamilton Crosser nanofluid through the cylinder with a rough surface 采用有限元法和田口分析法对卡森流体包裹体中的二、三汉密尔顿克罗斯纳米流体在粗糙表面圆柱体中的血流进行分析

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-02-20 DOI: 10.1007/s11043-025-09766-z

Muhammad Sohail, Umar Nazir, Ibrahim Mahariq, Yasser Elmasry

{"title":"Implementation of FEM and Taguchi analysis on blood flow for Casson fluid inclusion of di- and tri-Hamilton Crosser nanofluid through the cylinder with a rough surface","authors":"Muhammad Sohail, Umar Nazir, Ibrahim Mahariq, Yasser Elmasry","doi":"10.1007/s11043-025-09766-z","DOIUrl":"10.1007/s11043-025-09766-z","url":null,"abstract":"<div><p>In developing considered occurrence phenomena, the proffered research study is conducted on account of blood motion along with chemically reactive Casson fluid exposed to a circular cylinder, including a rough surface. Moreover, Lorentz force is invoked across the hybrid nanoliquid. The innovation behind this influential approach is based on the assumption of heat production and consumption. Given cooling procedures and the thermal energy mechanism, copper, silver, and titanium oxide within the blood occurrence are used in the proposed study. For the development of the current flow problem, we have considered the Cartesian coordinate system. Due to the complexity of the proffered formulated model, the governing dimensionless set of equations is handled using a traditional numerical approach, the finite element method (FEM). Further, the efficient role of the pertinent constraints arises across the flow phenomena demonstrated graphically and presented in tabular form. Comparative analysis demonstrates that the movement of copper, silver, and titanium oxide in the blood is more intense than the movement of copper and silver in the blood. Meanwhile, thermal energy produced by using copper, silver, and titanium oxide in the blood is much higher in comparison to thermal energy for copper and silver with blood. Moreover, the Nusselt number also depicts an accelerated demeanor for copper, silver, and titanium oxide in the blood in contrast to the production of silver and copper with blood. We have emphasized the proffered study relevance with biomedical applications, specifically its incorporation for understanding blood occurrence within complex geometries and the effects of nanoliquid dispersion in the flow dynamics.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143455597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nanoindentation loading rate sensitivity of the mechanical behavior of cured isotropic conductive adhesives 纳米压痕加载率对固化各向同性导电胶粘剂力学性能的敏感性

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-02-19 DOI: 10.1007/s11043-025-09767-y

Xinkuo Ji, Gesheng Xiao, Zhidan Zhou, Chenfei Song, Huanhuan Lu

{"title":"Nanoindentation loading rate sensitivity of the mechanical behavior of cured isotropic conductive adhesives","authors":"Xinkuo Ji, Gesheng Xiao, Zhidan Zhou, Chenfei Song, Huanhuan Lu","doi":"10.1007/s11043-025-09767-y","DOIUrl":"10.1007/s11043-025-09767-y","url":null,"abstract":"<div><p>The mechanical properties of isotropic conductive adhesive (ICA) have received increasing attention due to its widespread application in microelectronic packaging. In this work, the loading and strain rate sensitivity of cured epoxy-based ICA were investigated using nanoindentation. The ICA was prepared and indented under quasi-static and continuous stiffness measurement (CSM) modes under varying loading rates (<span>(dot{P})</span>) and loading strain rates (<span>(dot{P} / P)</span>). The results demonstrate a loading/strain rate hardening effect on the hardness of ICA. Compared with quasi-static test measurement, the CSM mode seems to be a more effective measurement for the hardness results of ICA. During nanoindentation, a competitive interaction between hardening and softening mechanisms was observed: softening dominated at higher loading strain rates, while hardening prevailed at lower rates. Under both loading modes, creep displacement and creep strain rate increased with strain/loading rate. In addition, the creep displacement rose rapidly during the initial holding time before stabilizing, while the corresponding creep strain rate decreased progressively to a steady-state creep stage.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11043-025-09767-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nonlinear relaxation behavior and competing aging mechanisms in GAP-based propellants under thermal aging 热老化下gap基推进剂的非线性松弛行为及竞争老化机制

IF 2.1 4区材料科学

Mechanics of Time-Dependent Materials Pub Date : 2025-02-17 DOI: 10.1007/s11043-025-09764-1

Jiangtao Wang, Guanglong Zhang, Li Yang, Xiangyang Liu, Ningfei Wang

{"title":"Nonlinear relaxation behavior and competing aging mechanisms in GAP-based propellants under thermal aging","authors":"Jiangtao Wang, Guanglong Zhang, Li Yang, Xiangyang Liu, Ningfei Wang","doi":"10.1007/s11043-025-09764-1","DOIUrl":"10.1007/s11043-025-09764-1","url":null,"abstract":"<div><p>Glycidyl azide polymer (GAP)-based propellants, known for their high energy efficiency, exhibit unique nonlinear variations in viscoelastic behavior during thermal aging, which is distinct from the monotonic trends observed in traditional propellants. This paper investigates the relaxation behavior of GAP-based propellants subjected to thermal aging at 60 °C. Nuclear Magnetic Resonance and high-performance liquid chromatography analyses are conducted to reveal the underlying mechanisms driving the nonlinear relaxation response. The aging process is classified into three distinct stages: an initial phase dominated by post-curing reactions, followed by competing effects from crosslink network scission, and plasticizer degradation. These competing mechanisms affect the relaxation through microscopic changes in free volume, resulting in complex viscoelastic responses. A predictive model is developed for the relaxation modulus to take into account of these aging mechanisms, with capability to capture the nonlinear fluctuations in the aging shift factor. The proposed model provides accurate predictions of relaxation behavior during thermal aging, including the long-term performance of GAP-based propellants.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"29 1","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0