مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

تحلیل تجربی بار کمانش ورق کامپوزیتی ساندویچی با هسته لوزی شکل با استفاده از رهیافت همبستگی ارتعاشی

نوع مقاله : پژوهشی اصیل

نویسندگان
دانشکده مهندسی مکانیک، دانشگاه تربیت مدرس، تهران، ایران
چکیده
در حال حاضر سازه‌های کامپوزیتی دارای کاربردهای زیادی در صنایع مختلفی ازجمله هوافضا، خودرو، دریایی و پتروشیمی هستند. در اکثر این کاربردها، سازه تحت بارهای دینامیکی و استاتیکی قرار می‌گیرد و ممکن است دچار کمانش، ارتعاش و خستگی شود. بنابراین تحلیل استاتیکی و دینامیکی این سازه‌ها به‌منظور شناخت خصوصیات آنها ازجمله بار کمانش، فرکانس طبیعی و شکل مودهای ارتعاشی بسیار ضروری است. یکی از مهم‌ترین روش‌های غیر مخرب برای پیش‌بینی بار کمانش سازه روش همبستگی ارتعاشی است که اساس آن بر پایه تغییرات فرکانس با تغییر بار محوری بر سازه است. در این تحقیق به بررسی تجربی بار کمانش ورق کامپوزیتی ساندویچی با هسته مشبک لوزی کامپوزیتی پرداخته‌شده است. برای ساخت ورق‌های ساندویچی از روش رشته پیچی و لایه چینی دستی استفاده‌شده است. یکی از نمونه‌های ساخته شده تحت آزمایش مودال قرار گرفته و با روش همبستگی ارتعاشی تجربی بار کمانش سازه محاسبه شده است. در ادامه برای صحت‌سنجی نتایج به‌دست آمده از روش همبستگی ارتعاشی، بار کمانش چهار نمونه از طریق آزمون فشار محوری محاسبه شد. میزان خطا برای پیش‌بینی بار کمانش به کمک روش همبستگی ارتعاشی تجربی ۲/۱% به دست آمد و کارآیی روش همبستگی ارتعاشی تجربی برای ورق کامپوزیتی مشبک مورد تأیید قرار گرفت. همچنین با بررسی تأثیر بازه بار اعمالی بر دقت روش همبستگی ارتعاشی مشخص شد که به ازای بار اعمالی بیش از ۶۳% بار کمانش تجربی، دقت پیش‌بینی روش همبستگی ارتعاشی به مقدار قابل‌قبول می‌رسد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Experimental Analysis of Composite Sandwich Plates Buckling with Lozenge Core Using the Vibration Correlation Technique

نویسندگان English

M. Aghaei-Ruzbahani
D. Shahgholian-Ghahfarokhi
Gh. Rahimi
Mechanical Engineering Faculty, Tarbiat Modares University, Tehran, Iran
چکیده English

Currently, composite structures have many applications in various industries including aerospace, automotive, marine, and petrochemicals. In most of these applications, the structure is under dynamic and static loads and it can cause buckling, vibration, and fatigue. Therefore, the static and dynamic analysis of these structures is essential in order to understand their characteristics, including buckling, natural frequency, and the shape of vibrating modes. One of the most important non-destructive methods for predicting the buckling load of the structure is the vibrational correlation technique (VCT), which is based on frequency variations with the axial load. In this study, an experimental study of the buckling load of composite sandwich plates with lozenge core has been investigated. The hand lay-up method has been used for fabrication of the composite sandwich plates. One of the specimens was used for the modal test. In order to verify the results of the VCT, the buckling load of four specimens was calculated by the experimental buckling test. The error of VCT was 2.1 %. Hence, the efficiency of the VCT for composite sandwich plates with lattice core was confirmed. Also, by investigating the effect of applied load percentage on the accuracy of the VCT, it was found that for the applied load of more than 63% of the buckling load, the accuracy of prediction of the vibrational correlation technique is acceptable.

کلیدواژه‌ها English

Buckling
Vibration Correlation Technique (VCT)
Composite sandwich plate
Fabrication
Modal Analysis
Ambur DR, Rehfield LW. Effect of stiffness characteristics on the response of composite grid-stiffened structures. Journal of Aircraft. 1993;30(4):541-546. [Link] [DOI:10.2514/3.46377]
Laura PAA, Gutierrez RH, Sanzi HC, Elvira G. Buckling of circular, solid and annular plates with an intermediate circular support. Ocean Engineering. 2000;27(7):749-755. [Link] [DOI:10.1016/S0029-8018(99)00022-0]
Kim TD. Fabrication and testing of composite isogrid stiffened cylinder. Composite Structures. 1999;45(1):1-6. [Link] [DOI:10.1016/S0263-8223(98)00124-X]
Shahgholian-Ghahfarokhi D, Tahani V, Rahimi GH. Experimental and numerical investigation of the effect of longitudinal and horizontal ribs on flexural behavior of grid stiffened composite plates. Journal of Science and Technology of Composites. 2017;3(4):333-342. [Link]
Tahani V, Shahgholian D, Rahimi GH. Experimental and numerical investigation of effect of shape of ribs on flexural behavior of grid composite plates. Modares Mechanical Engineering. 2016;16(6):303-311. [Persian] [Link]
Yazdani M, Hossein R, Afaghi Khatibi A. An experimental investigation into the buckling of GFRP stiffened shells under axial loading. Scientific Research and Essay. 2009;4(9):914-920. [Link]
Shojaee T, Mohammadi B, Madoliat R. Experimental and numerical investigation of stiffener effects on buckling strength of composite laminates with circular cutout. Journal of Composite Materials. 2020;54(9):1141-1160. [Link] [DOI:10.1177/0021998319874101]
Chen L, Fan H, Sun F, Zhao L, Fang D. Improved manufacturing method and mechanical performances of carbon fiber reinforced lattice-core sandwich cylinder. Thin-Walled Structures. 2013;68:75-84. [Link] [DOI:10.1016/j.tws.2013.03.002]
Zhang H, Sun F, Fan H, Chen H, Chen L, Fang D. Free vibration behaviors of carbon fiber reinforced lattice-core sandwich cylinder. Composite Science and Technology. 2014;100:26-33. [Link] [DOI:10.1016/j.compscitech.2014.05.030]
Zarei M, Rahimi GH. Free vibration analysis of grid stiffened composite conical shells. Journal of Science and Technology of Composites. 2017;4(1):1-8. [Link]
Shahgholian-Ghahfarokhi D, Ghanadi A, Rahimi H. Experimental and numerical investigation of the free vibration of composite sandwich plates with lattice cores. Modares Mechanical Engineering. 2017;17(10):1-8. [Persian] [Link]
Sommerfeld A. A simple device to illustrate the buckling process. Unknown City: Zeitschrift des Verein Deutscher Ingenieure (ZVDI); 1905.pp. 1320-1323. [German] [Link]
Lurie H. Lateral vibrations as related to structural stability [Dissertation]. Pasadena: California Institute of Technology; 1950. [Link]
Sukajit P, Singhatanadgid P. Identification of buckling load of thin plate using the vibration correlation technique. 21st Conference of Mechanical Engineering Network of Thailand, 2007, 17-19 October 2007, Chonburi Province, Thailand. Unknown City: TSME: 2007. [Link]
Singhatanadgid P, Sukajit P. Determination of buckling load of rectangular plates using measured vibration data. Proceeding of the International Conference on Experimental Mechanics and Seventh Asian Conference on Experimental Mechanics, 2008, November, 8-11, Nanjing, China. Bellingham, Washington: SPIE; 2009. [Link] [DOI:10.1117/12.839274]
Abramovich H, Govich D, Grunwald A. Buckling prediction of panels using the vibration correlation technique. Progress in Aerospace Sciences. 2015;78:62-73. [Link] [DOI:10.1016/j.paerosci.2015.05.010]
Souza MA, Fok WC, Walker AC. Review of experimental techniques for thin-walled structures liable to buckling: Neutral and unstable buckling. Experimental Techniques. 1983;7(9):21-25. [Link] [DOI:10.1111/j.1747-1567.1983.tb01811.x]
Souza MA, Assaid LMB. A new technique for the prediction of buckling loads from nondestructive vibration tests. Experimental Mechanics. 1991;31:93-97. [Link] [DOI:10.1007/BF02327558]
Jansen EL, Abramovich H, Rolfes R. The direct prediction of buckling loads of shells under axial compression using VCT-towards an upgraded approach. Proceedings of the 27th Congress of the International Council of the Aeronautical Sciences, 2014, September, 7-12, ST. Petersburg, Russia. Ontario: ICAS; 2014. [Link]
Chaves-Vargas M, Dafnis A, Reimerdes HG, Schröder KU. Modal parameter identification of a compression-loaded CFRP stiffened plate and correlation with its buckling behaviour. Progress in Aerospace Science. 2015;78:39-49. [Link] [DOI:10.1016/j.paerosci.2015.05.009]
Arbelo MA, Kalnins K, Ozolins O, Skukis E, Castro SG, Degenhardt R. Experimental and numerical estimation of buckling load on unstiffened cylindrical shells using a vibration correlation technique. Thin-Walled Structures. 2015;94:273-9. [Link] [DOI:10.1016/j.tws.2015.04.024]
Arbelo MA, Almeida S, Donadon MV, Rett SR, Degenhardt R, Castro SGP, et al. Vibration correlation technique for the estimation of real boundary conditions and buckling load of unstiffened plates and cylindrical shells. Thin-Walled Structures. 2014;79:119-128. [Link] [DOI:10.1016/j.tws.2014.02.006]
Kalnins K, Arbelo MA, Ozolins O, Skukis E, Castro SGP, Degenhardt R. Experimental nondestructive test for estimation of buckling load on unstiffened cylindrical shells using vibration correlation technique. Shock and Vibration. 2015;2015:729684. [Link] [DOI:10.1155/2015/729684]
Skukis E, Ozolins O, Kalnins K, Arbelo MA. Experimental test for estimation of buckling load on unstiffened cylindrical shells by vibration correlation technique. Procedia Engineering. 2017;172:1023-30. [Link] [DOI:10.1016/j.proeng.2017.02.154]
Shahgholian Ghahfarokhi D, Raafat MR, Rahimi GH. Prediction of the critical buckling load of composite cylindrical shells by using vibration correlation technique. Journal of Science and Technology of Composites. 2018;5(3):359-368. [Link]
Shahgholian Ghahfarokhi D, Rahimi GH. Prediction of the critical buckling load of stiffened composite cylindrical shells with lozenge grid based on the nonlinear vibration analysis. Modares Mechanical Engineering. 2018;18(4):135-143. [Persian] [Link]
Shahgholian-Ghahfarokhi D, Rahimi G. Buckling load prediction of grid-stiffened composite cylindrical shells using the vibration correlation technique. Composites Science and Technology. 2018;167:470-481. [Link] [DOI:10.1016/j.compscitech.2018.08.046]
Gibson RF. Principles of composite material mechanics. Florida: CRC Press; 2011. [Link]