Applications in engineering science最新文献_第7页

Shrinkage properties of steel fiber reinforced concrete- A review 钢纤维混凝土的收缩性能综述

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-25 DOI: 10.1016/j.apples.2025.100244

Mohammad Abedi , Terje Kanstad , Stefan Jacobsen , Guomin Ji

Cracks induced by concrete shrinkage may allow corrosive agents to penetrate steel reinforced concrete and deteriorate the reinforcement. Adding randomly distributed steel fiber to concrete can reduce shrinkage and prevent the initiation of cracking, along with improving tensile strength and ductility. Autogenous shrinkage and drying shrinkage are the most important types of shrinkage in steel fiber reinforced concrete (SFRC). There is a general lack of knowledge related to the autogenous and drying shrinkage of SFRC. In the paper, the main factors that affect the autogenous shrinkage and drying shrinkage of SFRC are thoroughly examined through literature review. These factors include fiber volume, fiber geometry, curing method, water binder ratio (w/b), expansive agent, shrinkage mitigation, supplementary cementitious material (SCM), admixtures and hybridizing different fiber materials. It is concluded that increasing fiber volume up to some optimal volume, using expansive agents and shrinkage mitigation, as well as hybridizing different fibers, can reduce markedly the drying shrinkage. Furthermore, the water binder ratio, curing method and presence of silica fume, fly ash, and ground granulated blast furnace slag (GGBFS) influence shrinkage development in SFRC. In the last part, models predicting the autogenous and drying shrinkage of SFRC are discussed and new research is proposed.

混凝土收缩引起的裂缝可能使腐蚀剂渗入钢筋混凝土并使钢筋劣化。在混凝土中加入随机分布的钢纤维，可以减小收缩，防止开裂，提高抗拉强度和延性。自收缩和干燥收缩是钢纤维混凝土中最主要的收缩形式。人们普遍缺乏与SFRC自收缩和干燥收缩有关的知识。本文通过文献综述，对影响SFRC自收缩和干燥收缩的主要因素进行了深入研究。这些因素包括纤维体积、纤维几何形状、养护方法、水胶比（w/b）、膨胀剂、减缩剂、补充胶凝材料（SCM）、外加剂和不同纤维材料的杂交。综上所述，将纤维体积增加到一定的最佳体积，使用膨胀剂和减缩剂，以及不同纤维的杂交，可以显著降低纤维的干燥收缩率。此外，水胶比、养护方式以及硅灰、粉煤灰和磨粒高炉渣（GGBFS）的存在都会影响SFRC的收缩发展。最后，讨论了SFRC自收缩和干燥收缩的预测模型，并提出了新的研究方向。

{"title":"Shrinkage properties of steel fiber reinforced concrete- A review","authors":"Mohammad Abedi , Terje Kanstad , Stefan Jacobsen , Guomin Ji","doi":"10.1016/j.apples.2025.100244","DOIUrl":"10.1016/j.apples.2025.100244","url":null,"abstract":"<div><div>Cracks induced by concrete shrinkage may allow corrosive agents to penetrate steel reinforced concrete and deteriorate the reinforcement. Adding randomly distributed steel fiber to concrete can reduce shrinkage and prevent the initiation of cracking, along with improving tensile strength and ductility. Autogenous shrinkage and drying shrinkage are the most important types of shrinkage in steel fiber reinforced concrete (SFRC). There is a general lack of knowledge related to the autogenous and drying shrinkage of SFRC. In the paper, the main factors that affect the autogenous shrinkage and drying shrinkage of SFRC are thoroughly examined through literature review. These factors include fiber volume, fiber geometry, curing method, water binder ratio (w/b), expansive agent, shrinkage mitigation, supplementary cementitious material (SCM), admixtures and hybridizing different fiber materials. It is concluded that increasing fiber volume up to some optimal volume, using expansive agents and shrinkage mitigation, as well as hybridizing different fibers, can reduce markedly the drying shrinkage. Furthermore, the water binder ratio, curing method and presence of silica fume, fly ash, and ground granulated blast furnace slag (GGBFS) influence shrinkage development in SFRC. In the last part, models predicting the autogenous and drying shrinkage of SFRC are discussed and new research is proposed.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100244"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144535506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pull-out and push-off behavior of self-compacting concrete for precast structures after elevated temperature 高温作用下预制结构自密实混凝土的拉脱性能

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-10 DOI: 10.1016/j.apples.2025.100239

Balamurali Kanagaraj , N. Anand , Samuvel Raj R , Eva Lubloy

The present study aims to develop and evaluate a sustainable, cement-free self-compacting geopolymer concrete (SCGC) using recycled aggregates and to assess its performance under elevated temperature conditions. The main objective is to compare the bond and shear behavior of SCGC with conventional cement concrete (reference concrete) and cement-based self-compacting concrete (SCC) before and after fire exposure. Three concrete types were prepared namely, reference concrete, SCC, and SCGC. The SCC and SCGC mixes met EFNARC guidelines for self-compacting behavior. Specimens were subjected to elevated temperatures for 1 and 2 h. Post-heating performance was evaluated based on mass loss, compressive strength, bond stress (BS), and interfacial shear stress (ISS). Results showed that after 1 h of heating, SCGC exhibited the highest bond stress, followed by SCC and reference concrete. Mass loss for SCGC was lower (4.5 % after 1 h; 5.6 % after 2 h) than others. Strength losses after 2 h were severe (65 % for reference, 69 % for SCC, and 67 % for SCGC). Bond stress and ISS losses exceeded 90 % after 2 h, representing severe degradation. Increased heating also resulted in higher slip, reducing bond integrity. SCGC demonstrated better thermal resistance initially, but all concrete types experienced substantial performance loss after prolonged high-temperature exposure.

本研究旨在利用再生骨料开发和评估一种可持续的、无水泥的自密实地聚合物混凝土（SCGC），并评估其在高温条件下的性能。主要目的是比较SCGC与传统水泥混凝土（参考混凝土）和水泥基自密实混凝土（SCC）在火灾前后的粘结和剪切性能。制备了参考混凝土、SCC和SCGC三种混凝土类型。SCC和SCGC混合物符合EFNARC自密实行为准则。将试样置于高温下1和2小时。加热后的性能根据质量损失、抗压强度、粘结应力（BS）和界面剪切应力（ISS）进行评估。结果表明：加热1 h后，SCGC的粘结应力最大，SCC次之，参考混凝土次之；1 h后SCGC的质量损失较低（4.5%）；（2 h后5.6%）。2小时后强度损失严重（参考65%，SCC 69%, SCGC 67%）。2 h后，粘结应力和ISS损失超过90%，表现出严重的降解。增加的加热也会导致更高的滑移，降低粘合的完整性。SCGC最初表现出更好的耐热性，但在长时间高温暴露后，所有类型的混凝土都出现了显著的性能损失。

{"title":"Pull-out and push-off behavior of self-compacting concrete for precast structures after elevated temperature","authors":"Balamurali Kanagaraj , N. Anand , Samuvel Raj R , Eva Lubloy","doi":"10.1016/j.apples.2025.100239","DOIUrl":"10.1016/j.apples.2025.100239","url":null,"abstract":"<div><div>The present study aims to develop and evaluate a sustainable, cement-free self-compacting geopolymer concrete (SCGC) using recycled aggregates and to assess its performance under elevated temperature conditions. The main objective is to compare the bond and shear behavior of SCGC with conventional cement concrete (reference concrete) and cement-based self-compacting concrete (SCC) before and after fire exposure. Three concrete types were prepared namely, reference concrete, SCC, and SCGC. The SCC and SCGC mixes met EFNARC guidelines for self-compacting behavior. Specimens were subjected to elevated temperatures for 1 and 2 h. Post-heating performance was evaluated based on mass loss, compressive strength, bond stress (BS), and interfacial shear stress (ISS). Results showed that after 1 h of heating, SCGC exhibited the highest bond stress, followed by SCC and reference concrete. Mass loss for SCGC was lower (4.5 % after 1 h; 5.6 % after 2 h) than others. Strength losses after 2 h were severe (65 % for reference, 69 % for SCC, and 67 % for SCGC). Bond stress and ISS losses exceeded 90 % after 2 h, representing severe degradation. Increased heating also resulted in higher slip, reducing bond integrity. SCGC demonstrated better thermal resistance initially, but all concrete types experienced substantial performance loss after prolonged high-temperature exposure.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100239"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144280403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Solving an inverse problem with four unknown boundary conditions in a lid-driven cavity with heated walls using the levenberg-marquardt method 用levenberg-marquardt方法求解带有加热壁的盖驱动腔中四个未知边界条件的逆问题

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-26 DOI: 10.1016/j.apples.2025.100245

Mojtaba Khosravi, Mohammad Mohammadiun, Hamid Mohammadiun, Mohammad hossein Dibaei bonab, Vali parvaneh

This study investigates the application of the Levenberg-Marquardt method in solving inverse heat transfer problems for a lid-driven cavity with four unknown thermal boundary conditions. The direct problem is solved using computational fluid dynamics (CFD) techniques implemented in OpenFOAM, employing the URANS equations. The numerical framework is first validated against experimental data from literature for a cavity with known boundary conditions. The inverse analysis focuses on simultaneously estimating four wall temperatures using temperature measurements at various sensor locations. The effects of sensor quantity and placement, algorithm parameters (fractional increment and damping coefficient), and measurement noise on the solution accuracy are systematically examined. The algorithm demonstrates robust convergence using a fractional increment of 0.0001 and an initial damping value of 1.0. It also maintains stability and accuracy even when measurement noise reaches up to 10 % of the maximum temperature difference. Under various conditions, the proposed approach consistently converges in approximately 12 iterations, confirming its effectiveness for simultaneously estimating multiple thermal boundary conditions in enclosed cavities. This study contributes to the development of reliable inverse methods for industrial applications involving natural convection in temperature-controlled chambers.

本文研究了Levenberg-Marquardt方法在求解具有四种未知热边界条件的盖驱动腔的反传热问题中的应用。直接的问题是使用OpenFOAM中实现的计算流体动力学（CFD）技术，采用URANS方程来解决的。数值框架首先通过文献中已知边界条件的空腔实验数据进行验证。逆分析的重点是利用不同传感器位置的温度测量同时估计四壁温度。系统地考察了传感器数量和位置、算法参数（分数增量和阻尼系数）和测量噪声对求解精度的影响。该算法使用分数增量0.0001和初始阻尼值1.0证明了鲁棒收敛性。即使测量噪声达到最大温差的10%，它也能保持稳定性和准确性。在各种条件下，所提出的方法在大约12次迭代中始终收敛，证实了其同时估计封闭腔内多个热边界条件的有效性。这项研究有助于开发可靠的逆方法，用于工业应用，涉及温控室中的自然对流。

{"title":"Solving an inverse problem with four unknown boundary conditions in a lid-driven cavity with heated walls using the levenberg-marquardt method","authors":"Mojtaba Khosravi, Mohammad Mohammadiun, Hamid Mohammadiun, Mohammad hossein Dibaei bonab, Vali parvaneh","doi":"10.1016/j.apples.2025.100245","DOIUrl":"10.1016/j.apples.2025.100245","url":null,"abstract":"<div><div>This study investigates the application of the Levenberg-Marquardt method in solving inverse heat transfer problems for a lid-driven cavity with four unknown thermal boundary conditions. The direct problem is solved using computational fluid dynamics (CFD) techniques implemented in OpenFOAM, employing the URANS equations. The numerical framework is first validated against experimental data from literature for a cavity with known boundary conditions. The inverse analysis focuses on simultaneously estimating four wall temperatures using temperature measurements at various sensor locations. The effects of sensor quantity and placement, algorithm parameters (fractional increment and damping coefficient), and measurement noise on the solution accuracy are systematically examined. The algorithm demonstrates robust convergence using a fractional increment of 0.0001 and an initial damping value of 1.0. It also maintains stability and accuracy even when measurement noise reaches up to 10 % of the maximum temperature difference. Under various conditions, the proposed approach consistently converges in approximately 12 iterations, confirming its effectiveness for simultaneously estimating multiple thermal boundary conditions in enclosed cavities. This study contributes to the development of reliable inverse methods for industrial applications involving natural convection in temperature-controlled chambers.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100245"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144549802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microstructure and tribological characterization of thin wall of bimetallic austenitic steel fabricated through wire arc additive manufacturing (WAAM) 电弧增材制造（WAAM）双金属奥氏体钢薄壁的显微组织和摩擦学特性

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-10 DOI: 10.1016/j.apples.2025.100241

Rupendra S. Tanwar, Suyog Jhavar

Austenitic stainless steels, such as SS316L, are widely employed in thin rotary components like blades and impellers due to their exceptional thermal resistance, wear resistance, and corrosion properties. This study examines the dry sliding wear behaviour of wire arc additive manufactured (WAAM) austenitic bimetallic structures (BMS) comprising SS316L and SS309. Wear tests were conducted using a pin-on-disc tribometer with a flat-on-flat configuration, utilizing 3 mm square pins extracted from distinct regions of the base metals and their interface, tested against an EN31 steel disc (61 HRC). The initial average coefficient of friction (CoF) for SS316L ranged between 0.41 and 0.64, whereas the SS316L-SS309 interface demonstrated a lower CoF of 0.42 to 0.58, attributed to increased ferrite content and hardness during the initial running-in phase. X-ray diffraction results revealed the formation of iron oxides and chromium oxide on the worn surface of the plate. Microstructural and energy dispersive spectroscopy (EDS) analyses indicated that the higher ferrite content in SS309 and interface regions significantly enhanced wear resistance compared to SS316L. The wear mechanism transitioned from combined abrasive-adhesive wear to adhesive wear with plastic deformation and severe material loss. Analysis of wear debris confirmed progressive oxide layer removal during sliding, leading to increased wear. The superior hardness and ferritic phase in SS309 and interface regions contributed to improved wear resistance, underscoring the potential of austenitic BMS for applications requiring high wear performance. This study emphasizes the critical role of microstructural tailoring in optimizing wear characteristics in WAAM-fabricated austenitic BMS components.

奥氏体不锈钢，如SS316L，由于其优异的耐热性，耐磨性和腐蚀性能，广泛应用于叶片和叶轮等薄旋转部件。本研究考察了由SS316L和SS309组成的丝弧添加剂制造（WAAM）奥氏体双金属结构（BMS）的干滑动磨损行为。使用平对平配置的销对盘摩擦计进行磨损测试，使用从基本金属及其界面的不同区域提取的3mm方形销，对EN31钢盘（61 HRC）进行测试。SS316L的初始平均摩擦系数（CoF）在0.41 ~ 0.64之间，而SS316L- ss309界面的CoF较低，为0.42 ~ 0.58，这是由于初始磨合阶段铁素体含量和硬度的增加。x射线衍射结果显示，在磨损表面形成氧化铁和氧化铬。显微组织和能谱分析表明，SS309和界面区铁素体含量的增加显著提高了SS316L的耐磨性。磨损机理由磨料-黏着复合磨损向具有塑性变形和严重材料损失的黏着磨损转变。对磨损碎片的分析证实，在滑动过程中，氧化层逐渐去除，导致磨损增加。SS309和界面区域的高硬度和铁素体相有助于提高耐磨性，强调了奥氏体BMS在需要高磨损性能的应用中的潜力。本研究强调了微结构裁剪在优化waam制造的奥氏体BMS部件磨损特性中的关键作用。

{"title":"Microstructure and tribological characterization of thin wall of bimetallic austenitic steel fabricated through wire arc additive manufacturing (WAAM)","authors":"Rupendra S. Tanwar, Suyog Jhavar","doi":"10.1016/j.apples.2025.100241","DOIUrl":"10.1016/j.apples.2025.100241","url":null,"abstract":"<div><div>Austenitic stainless steels, such as SS316L, are widely employed in thin rotary components like blades and impellers due to their exceptional thermal resistance, wear resistance, and corrosion properties. This study examines the dry sliding wear behaviour of wire arc additive manufactured (WAAM) austenitic bimetallic structures (BMS) comprising SS316L and SS309. Wear tests were conducted using a pin-on-disc tribometer with a flat-on-flat configuration, utilizing 3 mm square pins extracted from distinct regions of the base metals and their interface, tested against an EN31 steel disc (61 HRC). The initial average coefficient of friction (CoF) for SS316L ranged between 0.41 and 0.64, whereas the SS316L-SS309 interface demonstrated a lower CoF of 0.42 to 0.58, attributed to increased ferrite content and hardness during the initial running-in phase. X-ray diffraction results revealed the formation of iron oxides and chromium oxide on the worn surface of the plate. Microstructural and energy dispersive spectroscopy (EDS) analyses indicated that the higher ferrite content in SS309 and interface regions significantly enhanced wear resistance compared to SS316L. The wear mechanism transitioned from combined abrasive-adhesive wear to adhesive wear with plastic deformation and severe material loss. Analysis of wear debris confirmed progressive oxide layer removal during sliding, leading to increased wear. The superior hardness and ferritic phase in SS309 and interface regions contributed to improved wear resistance, underscoring the potential of austenitic BMS for applications requiring high wear performance. This study emphasizes the critical role of microstructural tailoring in optimizing wear characteristics in WAAM-fabricated austenitic BMS components.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100241"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144298646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Coupling FVM and FEM using coupling code with Code Saturne and Code ASTER 用code Saturne和code ASTER耦合代码耦合FVM和FEM

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-19 DOI: 10.1016/j.apples.2025.100237

Dimitri Vesvard , Philippe Karamian-Surville , Nizar Abcha

The mechanics of fluid–structure interactions (FSI) originated from the necessity to understand complex phenomena involving multiple scientific disciplines. In solid mechanics, fluids are often considered to have a negligible influence or are modeled in a simplified manner, while in fluid mechanics, solids are typically treated as boundary conditions. Although these approximations are valid in many cases, they become insufficient when strong interactions between solids and fluids occur, requiring a coupled approach for accurate modeling. This research investigates the behavior of fluid–structure interactions and presents a fully customized coupling algorithm integrating two open-source solvers: Code_Saturne for fluid dynamics and Code_Aster for structural analysis. The algorithm is implemented on the AUSTRAL cluster, hosted by CRIANN (Centre Régional Informatique et d’Applications Numériques de Normandie).

流固相互作用力学（FSI）起源于理解涉及多个学科的复杂现象的必要性。在固体力学中，流体通常被认为具有可忽略的影响或以简化的方式建模，而在流体力学中，固体通常被视为边界条件。虽然这些近似在许多情况下是有效的，但当固体和流体之间发生强相互作用时，它们就变得不够了，需要采用耦合方法进行精确建模。本研究研究了流体-结构相互作用的行为，并提出了一个完全定制的耦合算法，该算法集成了两个开源求解器：用于流体动力学的Code_Saturne和用于结构分析的Code_Aster。该算法是在由CRIANN（法国诺曼底区域信息与应用中心）托管的AUSTRAL集群上实现的。

引用次数: 0

Experimental study on the influence of ultrasonic surface treatment on freeze-thaw and carbonation resistance properties of concrete 超声波表面处理对混凝土抗冻融和抗碳化性能影响的试验研究

IF 2.1 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-08-04 DOI: 10.1016/j.apples.2025.100251

Ruiting Ba , Wei Chen , Mingshan Li , Yong Shi

Cement concrete, the predominant modern construction material, exhibits poor durability owing to its porous microstructure. Surface treatment has emerged as an effective method to enhance concrete's durability. While surface coating or modification techniques are commonly employed, they necessitate additional materials, thereby increasing engineering costs. In contrast, ultrasonic surface treatment(UST) of concrete offers a novel physical approach that requires no supplementary materials, rendering it a cost-effective and promising alternative. However, the frost resistance of ultrasonically treated concrete, particularly in the context of extensive use of supplementary cementitious materials, has not been extensively investigated in prior research.

This study investigates the use of UST to enhance the frost and carbonation resistance of concrete. Results show that UST significantly improves both properties. Specifically, the relative dynamic elastic modulus of treated concrete increased by 11.37%-19.31%, mass loss rate decreased by 32.25%-52.86%, carbonation depth reduced by 24.22%-26.16%, and the carbonation coefficient dropped from 3.302–3.463 to 2.357–2.441. These enhancements are attributed to the refinement of the concrete surface microstructure and the improvement of defects at the matrix-aggregate interface due to UST. Consequently, UST represents a beneficial complement to conventional air entrainment and coating methods for enhancing the frost and carbonation resistance of concrete.

水泥混凝土，主要的现代建筑材料，表现出较差的耐久性由于其多孔的微观结构。表面处理已成为提高混凝土耐久性的有效方法。虽然通常采用表面涂层或改性技术，但它们需要额外的材料，从而增加了工程成本。相比之下，混凝土的超声波表面处理（UST）提供了一种新的物理方法，不需要补充材料，使其成为一种具有成本效益和前景的替代方案。然而，超声波处理混凝土的抗冻性，特别是在大量使用补充胶凝材料的情况下，在先前的研究中尚未得到广泛的研究。本研究探讨了UST在提高混凝土抗冻和抗碳化性能中的应用。结果表明，UST显著改善了这两种性能。其中，处理后混凝土的相对动弹性模量提高了11.37% ~ 19.31%，质量损失率降低了32.25% ~ 52.86%，碳化深度降低了24.22% ~ 26.16%，碳化系数从3.302 ~ 3.463降低到2.357 ~ 2.441。这些增强归因于混凝土表面微观结构的细化和基体-骨料界面缺陷的改善。因此，UST代表了传统的空气夹带和涂层方法的有益补充，以增强混凝土的抗冻性和抗碳化性。

{"title":"Experimental study on the influence of ultrasonic surface treatment on freeze-thaw and carbonation resistance properties of concrete","authors":"Ruiting Ba , Wei Chen , Mingshan Li , Yong Shi","doi":"10.1016/j.apples.2025.100251","DOIUrl":"10.1016/j.apples.2025.100251","url":null,"abstract":"<div><div>Cement concrete, the predominant modern construction material, exhibits poor durability owing to its porous microstructure. Surface treatment has emerged as an effective method to enhance concrete's durability. While surface coating or modification techniques are commonly employed, they necessitate additional materials, thereby increasing engineering costs. In contrast, ultrasonic surface treatment(UST) of concrete offers a novel physical approach that requires no supplementary materials, rendering it a cost-effective and promising alternative. However, the frost resistance of ultrasonically treated concrete, particularly in the context of extensive use of supplementary cementitious materials, has not been extensively investigated in prior research.</div><div>This study investigates the use of UST to enhance the frost and carbonation resistance of concrete. Results show that UST significantly improves both properties. Specifically, the relative dynamic elastic modulus of treated concrete increased by 11.37%-19.31%, mass loss rate decreased by 32.25%-52.86%, carbonation depth reduced by 24.22%-26.16%, and the carbonation coefficient dropped from 3.302–3.463 to 2.357–2.441. These enhancements are attributed to the refinement of the concrete surface microstructure and the improvement of defects at the matrix-aggregate interface due to UST. Consequently, UST represents a beneficial complement to conventional air entrainment and coating methods for enhancing the frost and carbonation resistance of concrete.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100251"},"PeriodicalIF":2.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Finite element study of a vertical rotor with tilting pads supported by an elastic structure 弹性结构支撑倾斜盘垂直转子的有限元研究

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-06-27 DOI: 10.1016/j.apples.2025.100242

Simon Pääjärvi , Gudeta Benti , Jan-Olov Aidanpää , Rolf Gustavsson

Although the dynamics of vertical rotor bearing systems have been studied, the interaction between vertical rotors, bearings, and supporting structures - such as casings, bearing brackets, and foundations, remains less explored. This study presents a combined experimental and numerical investigation of a coupled vertical rotor system, incorporating a nonlinear, speed- and eccentricity-dependent bearing. The novelty lies in the description of a complex, vertical, rotor-bearing-support system incorporating a nonlinear journal bearing model, to capture the effects of the rotor’s vertical orientation, as typical of hydropower applications. The system features an elastic mid-span rotor supported by a flexible tower structure. The four-shoe tilting pad bearings impose significant stiffness variations and nonlinearities, connecting the stationary and rotating components. Modal analysis identifies the critical speeds of the flexible supporting structure, and simulations in the time domain are conducted for various run-up conditions, focusing on the bearing response across the structure’s first two natural frequencies. The results show qualitative and quantitative agreement between the experimental and simulated responses, highlighting the distinct dynamic behaviors of the upper and lower bearings. The bearing response at the structure’s first critical speed is studied and demonstrates improved accuracy during critical conditions. This model builds on established methods to accurately represent vertical rotor dynamics with nonlinear, eccentricity- and speed-dependent bearing models, while extending its applicability to more complex systems by incorporating bearing support flexibility, effectively providing a framework for simulating systems such as complete hydropower units.

虽然垂直转子轴承系统的动力学已经被研究过，但是垂直转子、轴承和支撑结构（如机壳、轴承支架和基础）之间的相互作用仍然很少被探索。本研究提出了一个结合实验和数值研究的耦合垂直转子系统，包括一个非线性，速度和偏心依赖轴承。新颖之处在于描述了一个复杂的，垂直的，转子-轴承-支撑系统，结合非线性轴颈轴承模型，以捕捉转子垂直方向的影响，如典型的水电应用。该系统具有弹性跨中转子，由柔性塔结构支撑。四鞋倾斜垫轴承施加显著的刚度变化和非线性，连接固定和旋转组件。模态分析确定了柔性支撑结构的临界速度，并对各种助跑条件进行了时域仿真，重点研究了结构前两个固有频率上的轴承响应。结果表明，实验响应与模拟响应的定性和定量一致，突出了上下轴承不同的动力行为。研究了结构在第一个临界速度下的轴承响应，并证明了在临界条件下精度的提高。该模型建立在已有方法的基础上，利用非线性、偏心和转速相关的轴承模型精确表示转子垂直动力学，同时通过考虑轴承支撑的灵活性，将其适用性扩展到更复杂的系统，有效地为完整的水电机组等系统的仿真提供了框架。

{"title":"Finite element study of a vertical rotor with tilting pads supported by an elastic structure","authors":"Simon Pääjärvi , Gudeta Benti , Jan-Olov Aidanpää , Rolf Gustavsson","doi":"10.1016/j.apples.2025.100242","DOIUrl":"10.1016/j.apples.2025.100242","url":null,"abstract":"<div><div>Although the dynamics of vertical rotor bearing systems have been studied, the interaction between vertical rotors, bearings, and supporting structures - such as casings, bearing brackets, and foundations, remains less explored. This study presents a combined experimental and numerical investigation of a coupled vertical rotor system, incorporating a nonlinear, speed- and eccentricity-dependent bearing. The novelty lies in the description of a complex, vertical, rotor-bearing-support system incorporating a nonlinear journal bearing model, to capture the effects of the rotor’s vertical orientation, as typical of hydropower applications. The system features an elastic mid-span rotor supported by a flexible tower structure. The four-shoe tilting pad bearings impose significant stiffness variations and nonlinearities, connecting the stationary and rotating components. Modal analysis identifies the critical speeds of the flexible supporting structure, and simulations in the time domain are conducted for various run-up conditions, focusing on the bearing response across the structure’s first two natural frequencies. The results show qualitative and quantitative agreement between the experimental and simulated responses, highlighting the distinct dynamic behaviors of the upper and lower bearings. The bearing response at the structure’s first critical speed is studied and demonstrates improved accuracy during critical conditions. This model builds on established methods to accurately represent vertical rotor dynamics with nonlinear, eccentricity- and speed-dependent bearing models, while extending its applicability to more complex systems by incorporating bearing support flexibility, effectively providing a framework for simulating systems such as complete hydropower units.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100242"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of hydraulic and pneumatic flow in a proportional solenoid valve 比例电磁阀中液压流量与气动流量的比较

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-07-19 DOI: 10.1016/j.apples.2025.100248

Joachim Daehn , Andreas Wierschem , Eberhard Ultsch

In serial testing of hydraulic solenoid valves as part of the manufacturing process, the use of liquid mediums poses various challenges, including inconvenient part handling, frequent exchange of fluids and expensive maintenance of machinery. The present study investigates the feasibility of using gaseous mediums as an alternative for hydraulic testing without compromising established hydraulic testing standards. Using an exemplary 2/2 hydraulic proportional valve, we carried out experiments using both gaseous and liquid mediums. The experimental data indicates a consistent correlation between the two fluids across relevant pressure levels, alongside an accurate reproduction of key variables. Based on these results, a generalized methodology for determining the applicability of pneumatic methods to test similar hydraulic valve types is proposed. Corresponding Computational Fluid Dynamics (CFD) analyses reveal that supersonic velocities occur in the contraction area during pneumatic testing, resembling characteristics often found in supersonic nozzle flows. The simulations further indicate considerable differences in the flow-induced forces among the two fluids in some regions within the flow domain. Nonetheless, critical testing parameters are not affected by these effects, therefore the correlation is preserved.

作为制造过程的一部分，在液压电磁阀的系列测试中，液体介质的使用带来了各种挑战，包括不方便的零件处理，频繁的流体交换和昂贵的机械维护。本研究探讨了使用气体介质作为水力测试的替代方法的可行性，而不影响已建立的水力测试标准。使用示例性的2/2液压比例阀，我们在气体和液体介质中进行了实验。实验数据表明，在相关压力水平上，两种流体之间存在一致的相关性，并精确再现了关键变量。基于这些结果，提出了一种确定气动方法对类似液压阀类型测试适用性的通用方法。相应的计算流体动力学（CFD）分析表明，在气动测试过程中，收缩区出现了超声速，这与超声速喷管流动的特征相似。模拟进一步表明，在流域内的某些区域，两种流体之间的流致力存在相当大的差异。尽管如此，关键的测试参数不受这些影响，因此相关性被保留。

{"title":"Comparison of hydraulic and pneumatic flow in a proportional solenoid valve","authors":"Joachim Daehn , Andreas Wierschem , Eberhard Ultsch","doi":"10.1016/j.apples.2025.100248","DOIUrl":"10.1016/j.apples.2025.100248","url":null,"abstract":"<div><div>In serial testing of hydraulic solenoid valves as part of the manufacturing process, the use of liquid mediums poses various challenges, including inconvenient part handling, frequent exchange of fluids and expensive maintenance of machinery. The present study investigates the feasibility of using gaseous mediums as an alternative for hydraulic testing without compromising established hydraulic testing standards. Using an exemplary 2/2 hydraulic proportional valve, we carried out experiments using both gaseous and liquid mediums. The experimental data indicates a consistent correlation between the two fluids across relevant pressure levels, alongside an accurate reproduction of key variables. Based on these results, a generalized methodology for determining the applicability of pneumatic methods to test similar hydraulic valve types is proposed. Corresponding Computational Fluid Dynamics (CFD) analyses reveal that supersonic velocities occur in the contraction area during pneumatic testing, resembling characteristics often found in supersonic nozzle flows. The simulations further indicate considerable differences in the flow-induced forces among the two fluids in some regions within the flow domain. Nonetheless, critical testing parameters are not affected by these effects, therefore the correlation is preserved.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100248"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144694404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Digitizing SMEs in the EU: A scalable model for retrofitting machinery to Industry 4.0 欧盟中小企业数字化：工业4.0机械改造的可扩展模型

IF 2.2 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-05-26 DOI: 10.1016/j.apples.2025.100230

Gabriel Gašpar , Roman Budjač , Maroš Valášek , Martin Bartoň , Tomáš Meravý , Maximilián Strémy

Small and Medium-sized Enterprises (SMEs) have faced significant economic challenges since the COVID-19 pandemic, compounded by high inflation, rising energy costs, and the cessation of government financial support. War-related disruptions in Europe have further exacerbated these issues. As the backbone of the European economy, SMEs must embrace Industry 4.0 to remain competitive. However, many lack the resources or expertise to adopt smart technologies. This article proposes a cost-effective, scalable model to guide SMEs in transitioning towards Industry 4.0 by retrofitting existing machinery. By assessing machinery readiness and identifying critical areas for digitization, the model enables targeted investments that optimize production and reduce costs. A gradual, tailored approach ensures alignment with SMEs’ financial and technical capacities, fostering modernization and long-term growth. The successful implementation of the AFB production system highlights the feasibility of retrofitting existing systems to meet modern manufacturing demands.

自2019冠状病毒病大流行以来，中小企业面临着重大的经济挑战，加上高通胀、能源成本上涨和政府停止财政支持，情况更加复杂。欧洲与战争有关的混乱进一步加剧了这些问题。作为欧洲经济的支柱，中小企业必须拥抱工业4.0以保持竞争力。然而，许多国家缺乏采用智能技术的资源或专业知识。本文提出了一个具有成本效益，可扩展的模型，通过改造现有机械来指导中小企业向工业4.0过渡。通过评估机器准备情况并确定数字化的关键领域，该模型可以实现有针对性的投资，从而优化生产并降低成本。采取循序渐进、量身定制的方式，确保与中小企业的资金和技术能力保持一致，促进现代化和长期增长。空军基地生产系统的成功实施突出了改造现有系统以满足现代制造需求的可行性。

{"title":"Digitizing SMEs in the EU: A scalable model for retrofitting machinery to Industry 4.0","authors":"Gabriel Gašpar , Roman Budjač , Maroš Valášek , Martin Bartoň , Tomáš Meravý , Maximilián Strémy","doi":"10.1016/j.apples.2025.100230","DOIUrl":"10.1016/j.apples.2025.100230","url":null,"abstract":"<div><div>Small and Medium-sized Enterprises (SMEs) have faced significant economic challenges since the COVID-19 pandemic, compounded by high inflation, rising energy costs, and the cessation of government financial support. War-related disruptions in Europe have further exacerbated these issues. As the backbone of the European economy, SMEs must embrace Industry 4.0 to remain competitive. However, many lack the resources or expertise to adopt smart technologies. This article proposes a cost-effective, scalable model to guide SMEs in transitioning towards Industry 4.0 by retrofitting existing machinery. By assessing machinery readiness and identifying critical areas for digitization, the model enables targeted investments that optimize production and reduce costs. A gradual, tailored approach ensures alignment with SMEs’ financial and technical capacities, fostering modernization and long-term growth. The successful implementation of the AFB production system highlights the feasibility of retrofitting existing systems to meet modern manufacturing demands.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100230"},"PeriodicalIF":2.2,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Prediction of fatigue cracking in asphaltic pavement under local traffic conditions: Application to Semel-Patel highway-Duhok 局部交通条件下沥青路面疲劳开裂预测——在Semel-Patel - duhok公路上的应用

IF 2.1 Q2 ENGINEERING, MULTIDISCIPLINARY

Applications in engineering science

Pub Date : 2025-09-01 Epub Date: 2025-08-10 DOI: 10.1016/j.apples.2025.100255

Noor Akram Alaani

Fatigue cracking was among the most prevalent types of distress affecting asphalt concrete pavements in Iraq, which had been exacerbated by base destabilisation and inadequate subgrade drainage and resulted from recurrent traffic loads that exceeded design specifications. The study focused on a 15-kilometer section of the Semel-Patel Highway near Duhok, where this type of cracking had significantly increased maintenance costs, however addressing it could help reducing expenditures on long term. The NCHRP mechanistic-empirical fatigue life prediction model (NCHRP 9–44A/PMED) was used to forecast the number of load repetitions that are possible until cracking occurred. Layer stiffness, traffic spectra, climate, and drainage condition were among the field condition inputs that had been adjusted by laboratory testing and field observations. Notable results revealed: the subgrade moisture and binders had a significant impact on the expected fatigue life, underscoring the significance of appropriate drainage enhancements and binder selection to prolong pavement life. This model proposed as a decision-support tool for pavement design optimization and maintenance management.

在伊拉克，疲劳开裂是影响沥青混凝土路面的最常见的损坏类型之一，由于基层不稳定和路基排水不足以及经常超过设计规格的交通负荷而加剧了这种情况。这项研究的重点是在Duhok附近的Semel-Patel高速公路的15公里路段，这种类型的裂缝大大增加了维护成本，但是解决它可以帮助减少长期支出。采用NCHRP力学-经验疲劳寿命预测模型（NCHRP 9-44A /PMED）对裂纹发生前可能的载荷重复次数进行预测。层刚度、交通谱、气候和排水条件是通过实验室测试和现场观测调整的现场条件输入。结果表明：路基含水率和粘结剂对预期疲劳寿命有显著影响，强调了适当加强排水和选择粘结剂对延长路面寿命的重要性。该模型可作为路面设计优化和养护管理的决策支持工具。

{"title":"Prediction of fatigue cracking in asphaltic pavement under local traffic conditions: Application to Semel-Patel highway-Duhok","authors":"Noor Akram Alaani","doi":"10.1016/j.apples.2025.100255","DOIUrl":"10.1016/j.apples.2025.100255","url":null,"abstract":"<div><div>Fatigue cracking was among the most prevalent types of distress affecting asphalt concrete pavements in Iraq, which had been exacerbated by base destabilisation and inadequate subgrade drainage and resulted from recurrent traffic loads that exceeded design specifications. The study focused on a 15-kilometer section of the Semel-Patel Highway near Duhok, where this type of cracking had significantly increased maintenance costs, however addressing it could help reducing expenditures on long term. The NCHRP mechanistic-empirical fatigue life prediction model (NCHRP 9–44A/PMED) was used to forecast the number of load repetitions that are possible until cracking occurred. Layer stiffness, traffic spectra, climate, and drainage condition were among the field condition inputs that had been adjusted by laboratory testing and field observations. Notable results revealed: the subgrade moisture and binders had a significant impact on the expected fatigue life, underscoring the significance of appropriate drainage enhancements and binder selection to prolong pavement life. This model proposed as a decision-support tool for pavement design optimization and maintenance management.</div></div>","PeriodicalId":72251,"journal":{"name":"Applications in engineering science","volume":"23 ","pages":"Article 100255"},"PeriodicalIF":2.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0