{"title":"Flutter investigation and deep learning prediction of FG composite wing reinforced with carbon nanotube","authors":"Aseel J. Mohammed, H. K. Kadhom","doi":"10.1515/cls-2022-0218","DOIUrl":"https://doi.org/10.1515/cls-2022-0218","url":null,"abstract":"Abstract The flutter of a composite wing reinforced with functionally graded carbon nanotubes (CNTs) has been investigated. A rectangular plate models a supersonic wing with cantilever boundary conditions. To determine displacement fields of a moderately thick plate, shear deformation theory is used. Using the Hamilton principle, a first-order piston theory was used to simulate supersonic airflow. This study examines four types of CNT thickness. Also, four different CNT distribution patterns are investigated. In a two-layer asymmetric composite, the effects of patch mass, mass distribution, fiber orientation angle, and distribution of CNTs were examined. Moreover, the results are compared and verified with other studies. A greater mass ratio led to a smaller flutter boundary, while a longer added mass increased the flutter boundary. A variation in the distribution pattern in CNT fiber orientation results in a distinct behavior of the flutter boundary for asymmetric composites with increasing orientation angles. The artificial neural network is utilized to predict the damping ratio, and the results showed great accuracy compared to the study results. Hyperparameter tuning is employed for better optimizing the predictive models.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":"76 19","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139125075","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}
Dian Purnamasari, T. Tuswan, T. Muttaqie, Irfan Eko Sandjaja, Andik Machfudin, Nandiko Rizal, Shinta Johar Alif Rahadi, Agus Sasmito, A. Zakki, O. Mursid
{"title":"Structural assessment of 40 ft mini LNG ISO tank: Effect of structural frame design on the strength performance","authors":"Dian Purnamasari, T. Tuswan, T. Muttaqie, Irfan Eko Sandjaja, Andik Machfudin, Nandiko Rizal, Shinta Johar Alif Rahadi, Agus Sasmito, A. Zakki, O. Mursid","doi":"10.1515/cls-2022-0219","DOIUrl":"https://doi.org/10.1515/cls-2022-0219","url":null,"abstract":"Abstract Due to the escalating demand for liquefied natural gas (LNG) as a low-emission and environmentally friendly energy source, ISO tank containers have emerged as an innovative solution to facilitate efficient and cost-effective mass transportation. The 40 ft ISO tank container, which encompasses a pressure vessel structure, is a versatile intermodal unit that seamlessly integrates into sea and land transportation networks. The main objective of this study is to present a comprehensive analysis for assessing the various frame design scenarios of the 40 ft ISO tank container for mini LNG carrier operation. The assessment is conducted under the provisions outlined in ASME Section VIII Division I code, which governs the design standards for boilers and pressure vessels. The finite-element analysis (FEA) scrutinizes three different structural design alternatives: frame thickness, the addition of support plates, and the addition of saddle supports, which are subjected to various loading conditions: stacking, lifting, and racking load tests. The analysis offers a comparative assessment of the safety level provided by the ASME design guidance in contrast to the FEA judgments based on ISO standards. It can be found that stacking and longitudinal load tests are more critical operational load scenarios. Increasing the frame thickness of the LNG ISO tank is more practical in increasing structural weight savings than adding more saddle supports and support plates.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":"18 2","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455948","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}
{"title":"Stripped and layered fabrication of minimal surface tectonics using parametric algorithms","authors":"Sabri Gokmen","doi":"10.1515/cls-2022-0210","DOIUrl":"https://doi.org/10.1515/cls-2022-0210","url":null,"abstract":"Abstract This article describes a parametric design and fabrication workflow influenced by Frei Otto’s form-finding experiments on soap films. The research investigates minimal surface geometry by combining physical and digital experiments in a computational framework. Operating on mesh topology, various parametric design tools and plug-ins in Rhinoceros/Grasshopper are presented to discuss the translation of minimal surfaces to flat strips suitable for planar fabrication using flexible materials. These tools are tested on a case study to show the automated design and manufacture of double-curved surfaces as double-layered strips running in perpendicular directions that can be affixed at point connections for structural stability. The development of the parametric workflow, material constraints, and stripped fabrication of layers are discussed.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135649669","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}
{"title":"Application of soft computing in estimating primary crack spacing of reinforced concrete structures","authors":"O. Alomari, M. Al-Rawashdeh","doi":"10.1515/cls-2022-0194","DOIUrl":"https://doi.org/10.1515/cls-2022-0194","url":null,"abstract":"Abstract The investigation related to the serviceability analysis, particularly in terms of crack spacing prediction, has remarkably increased recently. In addition, the prediction of serviceability analysis is highly dependent and influenced by different physical and material factors that contribute to the crack spacing of reinforced concrete (RC) structures. As a result, the cracking phenomenon has not been fully grasped due to these factors’ wide variety and complexity. Recently, soft computing techniques have gained considerable popularity due to their capability of learning and producing generalized solutions and exhibiting desirable performance in terms of time, effort, and cost. However, the literature on crack spacing prediction using various machine learning approaches is limited and insufficient. Therefore, this article is dedicated to estimating the primary crack spacing of RC structures using different machine learning methods. As a part of the study, the findings of these approaches will be computed and compared to the benchmark experimental results. Besides, the results of the developed models will be compared against that of available approaches in the literature to highlight their reliability. Furthermore, a parametric assessment will be conducted to emphasize the most influencing input parameter on the primary crack spacing of RC structures.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48248937","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}
Fattah Maulana, A. Prabowo, Ridwan Ridwan, U. Ubaidillah, D. Ariawan, J. Sohn, N. Muhayat, D. D. P. Tjahjana, Q. T. Do
{"title":"Antiballistic material, testing, and procedures of curved-layered objects: A systematic review and current milestone","authors":"Fattah Maulana, A. Prabowo, Ridwan Ridwan, U. Ubaidillah, D. Ariawan, J. Sohn, N. Muhayat, D. D. P. Tjahjana, Q. T. Do","doi":"10.1515/cls-2022-0200","DOIUrl":"https://doi.org/10.1515/cls-2022-0200","url":null,"abstract":"Abstract Antiballistics are used as personal protective equipment required by military and police personnel. They have been mentioned frequently in recent decades due to the increasing cases of war. Several studies have reviewed the development of antiballistic technology. However, there needs to be more discussion on and systematic reviews of the current milestones of antiballistic materials, testing, and procedures. In addition, compared to other fields, antiballistic studies are rarely carried out by public researchers because research on weapons is still a sensitive topic. Researchers who want to discuss antiballistics must cooperate with the country's defense and security agencies. This article aims to present a summary on and the development of scientific research on the theoretical concept of impact, the experimental approach for ballistic tests on advanced materials, the idealization of ballistic tests in computational mechanic simulations, and milestones of technical apparatus for ballistic performance measurement, over a period of more than 500 years. Thus, this analysis makes an excellent contribution to the field of antiballistics. This article review is based on hundreds of international journals and websites that are still active and can be accounted for legally. The results show that research related to antiballistics will continue to grow yearly.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43643984","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}
El-Sayed Habib, Araby I. Mahdy, G. Ali, A. El-Megharbel, Eman El-Shrief
{"title":"Analysis of a thick cylindrical FGM pressure vessel with variable parameters using thermoelasticity","authors":"El-Sayed Habib, Araby I. Mahdy, G. Ali, A. El-Megharbel, Eman El-Shrief","doi":"10.1515/cls-2022-0207","DOIUrl":"https://doi.org/10.1515/cls-2022-0207","url":null,"abstract":"Abstract In this study, a closed-form analytical solution is derived to compute the stress formulations for a thick cylindrical pressure vessel made of functionally graded material (FGM) with varying parameters, which are mechanical and thermal boundary conditions. The assumed mechanical boundary condition is the time-dependent pressure acting on the internal surface of the cylinder, while the assumed thermal boundary condition is the transient temperature distribution over the cylinder thickness. The material properties are considered to be graded exponentially in the radial direction, except Poisson’s ratio which is assumed to be constant. The stress and displacement formulations are evaluated using Mathematica software for the uncoupled thermo-mechanical analysis. The results of radial, hoop, and axial stress are plotted at various times for two FGM cylinders, the SS304-Alumina FGM cylinder and the TZM-SIC FGM cylinder, to study the impact of using different materials for the same boundary conditions on the results. The results obtained in this study are beneficial as these contribute to the design and modeling of cylinders that are exposed to time-dependent internal pressure and transient temperature profiles.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49664864","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}
{"title":"MD-based study on the deformation process of engineered Ni–Al core–shell nanowires: Toward an understanding underlying deformation mechanisms","authors":"Bassam A. Mohammed, R. S. Batbooti","doi":"10.1515/cls-2022-0188","DOIUrl":"https://doi.org/10.1515/cls-2022-0188","url":null,"abstract":"Abstract Nowadays, core/shell structures due to very high thermal and electrical conductivity are taken into account in the manufacture of many industrial sensors and catalysis. Ni–Al core/shell structures are known as one of the most practical materials due to their high chemical stabilities at elevated temperatures. Since the evaluation of the mechanical properties of the industrial core/shell catalysts is crucial, identification of the mechanism responsible for their plastic deformation has been a challenging issue. Accordingly, in this study, the mechanical properties and plastic deformation process of Ni–Al core/shell structures were investigated using the molecular dynamics method. The results showed that due to the high-stress concentration in the Ni/Al interface, the crystalline defects including dislocations and stacking faults nucleate from this region. It was also observed that with increasing temperature, yield strength and elastic modulus of the samples decrease. On the other hand, increasing the temperature promotes the heat-activated mechanisms, which reduces the density of dislocations and stacking faults in the material. Consequently, the obstacles in the slip path of the dislocations as well as dislocation locks are reduced, weakening the mechanical properties of the samples.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":"10 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41360336","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}
{"title":"Studying the effect of embedded length strength of concrete and diameter of anchor on shear performance between old and new concrete","authors":"Rana F. Yousef, H. Muteb, A. Ibrahim","doi":"10.1515/cls-2022-0184","DOIUrl":"https://doi.org/10.1515/cls-2022-0184","url":null,"abstract":"Abstract This article illustrates the specifications required to accurately design, specify, and install embedded anchor bolts between old and new concrete composite specimens for concrete repair or reinforcing of collapse concrete a research hotspot. The concrete slabs are facing a major challenge with deterioration, especially for reinforcement corrosion caused mainly by severe cycles of various chemical attacks. In this research, the impact of using contact plates between composite specimens was investigated by testing grouped specimens, thereby the models were divided into two groups, which tested under static load. The findings of a series of tests conducted to evaluate the structural behavior of shear connections (by pushout test) by including many parameters; the diameter (8, 12 and 16 mm), bounding between different compressive strength should be changed [normal concert (NC) mixes , ultra-high performance fiber concrete (UHPFC), and self-compacting mortar (SCM)]. Also, the embedded length of bolts was varied from 70, 130, to 190 mm. These parameters were studied individually in two groups. The first group was without contact plate and the second group was with contact plate. Experimental findings were obtained and reported, including the failure modes, maximum resistance, slippage capacity, and load–slip characteristic responses of the connections. Based on the obtained data, a relationship between the studied parameters was investigated. Experimental findings showed that the ultimate strength of rough surface specimens (without contact plate) was about 31% greater than that of smooth surface specimens (with contact plate), and obviously, all pushout specimens failed due to stud shank failure.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41488951","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}
{"title":"Structural function analysis of shear walls in sustainable assembled buildings under finite element model","authors":"Yaxian Cao","doi":"10.1515/cls-2022-0201","DOIUrl":"https://doi.org/10.1515/cls-2022-0201","url":null,"abstract":"Abstract With the quick progress of industrialization and urbanization, the construction industry has become one of the largest energy-consuming industries. However, the current prefabricated shear wall focuses on the upgrade of seismic function, with less analysis of the energy efficiency of the overall structure. In this study, a sustainable prefabricated building shear wall that takes into account both energy conservation and stress is first proposed, and then the shear wall is modelled by finite element method (FEM) software. Meanwhile, the force functions of the shear wall model, including concrete strength, axial condensability rate, and aspect rate, and finally the seismic function are verified. The experimental outcomes demonstrate that the maximum difference between the FEM analysis outcomes and the test data is only 10.66%, and the overall difference in the outcomes is relatively small. The larger the aspect rate of the proposed sustainable assembled shear wall model, the better the ductility of the member, and the bigger the axial condensability rate and concrete strength, the lower the ductility of the member. In the seismic function analysis, the maximum layer displacement angles of this shear wall are all less than 1/120, which is in line with the national seismic code. This indicates its good seismic function and provides a methodological reference for the upgrade of the structural function of shear walls.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48814144","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}
N. Kunla, T. Jearsiripongkul, S. Keawsawasvong, C. Thongchom, Jintara Lawongkerd, Peyman Roodgar Saffari, P. R. Saffari, N. Refahati
{"title":"Identification of crack location in metallic biomaterial cantilever beam subjected to moving load base on central difference approximation","authors":"N. Kunla, T. Jearsiripongkul, S. Keawsawasvong, C. Thongchom, Jintara Lawongkerd, Peyman Roodgar Saffari, P. R. Saffari, N. Refahati","doi":"10.1515/cls-2022-0196","DOIUrl":"https://doi.org/10.1515/cls-2022-0196","url":null,"abstract":"Abstract If not detected early, the cracks in structural components may ultimately result in the failure of the structure. This issue becomes even more critical when the component under investigation is a prosthesis placed in the human body. This study presents a crack location identification method based on the time domain in a cantilever beam of metallic biomaterials (CBMB). The absolute difference between the central difference approximation of the root mean square (RMS) of displacement of points on the cracked and uncracked beams was applied as a cracked location indicator. Captured time-domain data (displacement) at each node of the cracked and uncracked beams were processed into a central difference approximation of the RMS of displacement. Then, the crack could be detected by a sudden change of the cracked location indicator. The feasibility and effectiveness of the proposed method were validated by numerical simulations. The finite-element simulation of a CBMB with a transverse notch was analyzed in the numerical study. The notch or crack was detected along the beam under a moving load at various locations. A set of simulation experiments and numerical calculations was performed to determine whether the proposed identification method would accurately detect the location of a crack in a cantilever beam under a moving load compared to the location found by an exact solution method. The results showed that the proposed method was not only as able as the analytical method but also robust against noise: it was able to detect a crack precisely under 5% noise.","PeriodicalId":44435,"journal":{"name":"Curved and Layered Structures","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46602952","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}