مطالعه رفتار دینامیکی مخازن انعطاف‌پذیر بتنی استوانه‌ای هوایی و زمینی با پایه جداسازی شده

نوع مقاله : علمی - پژوهشی

نویسندگان

1 استادیار، دانشکده فنی و مهندسی، دانشگاه یاسوج، یاسوج، ایران

2 کارشناس ارشد مهندسی عمران،دانشکده فنی و مهندسی، دانشگاه یاسوج، یاسو.ج، ایران

3 دانشیار، دانشکده فنی و مهندسی، دانشگاه یاسوج، یاسو.ج، ایران

چکیده

مخازن ذخیره مایعات یکی از سازه‌های بسیار مهم در سیستم‌های تصفیه آب و فاضلاب و صنایع ذخیره مایعات سمی محسوب می‌شوند. یکی از بهترین روش‌های مراقبت از مخازن ذخیره‌سازی مایعات در برابر نیروهای زلزله، استفاده از سیستم‌های جداسازی لرزه‌ای می‌باشد. این سیستم‌ها با ایجاد تغییرمکان‌های قابل قبول در پایه‌ی روسازه ضمن جلوگیری از ورود روسازه به فازهای غیرخطی، از اعمال خسارت‌های احتمالی به این سازه‌ها محافظت می‌کند. از جمله روش‌های متداول به منظور مدلسازی مخازن، استفاده از مدل‌های مکانیکی معادل این سازه‌ها می‌باشد. آیین‌نامه‌های طراحی مخازن نیز با بهره‌گیری از این مدل‌ها، به ارائه‌ی معادلات و روابط حاکم به رفتار آن‌ها پرداخته‌اند. اما مدل‌های مکانیکی استفاده شده توسط آیین‌نامه‌ها و محققان قبلی، برای مخازن با دیواره‌ی صلب ارائه شده‌اند. تمامی مطالعات پیشین بر پایه‌ی همین مدل‌ها صورت گرفته است. در این تحقیق، با استفاده از یک مدل مکانیکی معادل مخازن بتنی استوانه‌ای که موضوع انعطاف‌پذیری دیواره را به صورت کاملا پیشرفته در نظر گرفته است، به بررسی پاسخ‌های لرزه‌ای مخازن بتنی زمینی و هوایی که تحت تأثیر حرکت افقی دو جهته‌ی زمین قرار گرفته است، پرداخته خواهد شد. نتایج نشان می‌دهد با انتخاب بهترین خصوصیات مکانیکی جداساز این سیستم‌ها، می‌توان پاسخ‌های لرزه‌ای این مخازن را تا حد زیادی بهبود بخشید,

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Dynamic behavior of elevated and ground-supported, base-isolated, flexible, concrete cylindrical fluid containers

نویسندگان [English]

  • Shamsedin Hashemi 1
  • Atefeh Ehteshami 2
  • Behrooz Rahmani 3
1 Assistant Professor, Department of Engineering, Yasouj University, Yasouj, Iran
2 MSc of Structural Engineering, Department of Engineering, Yasouj University, Yasouj, Iran
3 Associate Professor, Department of Engineering, Yasouj University, Yasouj, Iran
چکیده [English]

Liquid storage tanks are vital and have great importance in industrial facilities. One of the best ways to protect the fluid storage tanks against earthquake forces is the use of seismic isolation systems. These systems protect such structures against possible damage during an earthquake by allowing acceptable displacements at the base of the superstructures while preventing the superstructure from entering the nonlinear phases. One of the common methods for computer modeling of these structures is the use of equivalent mechanical models. It should be noted that, the mentioned equivalent mechanical models, are suggested for design of tanks by Standards and Codes. However, they are appropriate for rigid-wall tanks. On the other hand, the recent studies show that the seismic response of a rigid tank may be considerably less than that of a similar flexible tank. In this study, by using a state-of-the-art equivalent mechanical model of cylindrical concrete containers, that considers the issue of wall flexibility, the seismic responses of ground-supported and elevated concrete containers affected by the bi-directional horizontal motion of the earthquake is investigated. The results show that, by selecting the best mechanical properties of seismic base isolation systems, the seismic responses of these tanks can be greatly improved.

کلیدواژه‌ها [English]

  • Concrete containers
  • ground-supported
  • elevated
  • Base-isolation
  • Mechanical Model
[1] Hoskins, L.M. and Jacobsen, L.S. (1934). Water pressure in a tank caused by simulated earthquake. Bulletin of the Seismological Society of America, Vol.24, pp.1-32.
[2] Jacobsen, L.S. and Ayre, R.S. (1951). Hydrodynamic Experiments with Rigid Cylindrical Tanks Subjected to Transient Motions. Bulletin of the Seismological Society of America, Vol.41, pp. 313-340.
[3] Housner, G.W. (1957). Dynamic pressure on accelerated fluid containers. Bulletin of the Seismological Society of America, 47, 5-35.
[4] Housner G.W. (1963). The dynamic behavior of water tanks. Bulletin of the Seismological Society of America, 53, 381-387.
[5] Graham, E.W. and Rodriguez, A.M. (1963). Characteristics of fuel motion Which affect airplane dynamics. J Appl Mech, Vol. 19, pp. 381-387.
[6] Epstein, H.I. (1976). Seismic design of liquid storage tanks. Journal of the Structural Division, 102 (9): 1659-1673.
[7] Veletsos, A.S. (1974). Seismic effects in flexible liquid storage tanks. Proc. 5th World Conf. Earthquake Eng., Rome, Italy, 1, 630-639.
[8] Yang, J.Y. (1976). Dynamic behavior of fluid tank system. Ph.D. Thesis, Civil Engineering, Rice University, Houston, Tex.
[9] Clough, R.W. and Clough, D.P. (1977). Seismic response of flexible cylindrical tanks. Paper K 5/1 Trans. 4th International Conference on Structural Mechanics in Reactor Technology, San Francisco, CA.
[10] Clough, R.W. and Niwa, A. and Clough, D.P. (1979). Experimental seismic study of cylindrical tanks. Journal of the Structural Division, ASCE, Vol. 105, No. 12, pp. 2565-2590.
[11] Haroun, M.A. (1983). Vibration studies and tests of liquid storage tanks. Earthquake Engng. Struct. Dyn, 11, 190-206.
[12] Moradi, R. and Behnamfar, F. and Hashemi, S. (2017). Mechanical model for cylindrical flexible concrete tanks undergoing lateral excitation. Soil Dynamicc and Earthquake Engineering, 106,148-162.
[13] Chalhoub, M.S. and Kelly, J.M. (1990). Shake table test of cylindrical water tanks in base-isolated structures. ASCE Journal of Engineering Mechanics, 116, 1451-1472.
[14] Bo, L. and Jia-xiang, T. (1994). Vibration studies of base-isolated liquid storage tanks. Comp. and Struct, 52(5), 1051-1059.
[15] Kim, N.S. and Lee, D.G. (1995). Pseudo-dynamic test for evaluation of seismic performance of base-isolated liquid storage tanks. Engineering Structures, 17(3), 198-208. 
[16] Shenton, H.W. and Hampton, F.P. (1999). Seismic response of isolated elevated water tanks. Journal of Structural Engineering, ASCE, Vol. 125, No. 9, pp. 965–976.
[17] Shrimali, M.K. and Jangid, R.S. (2002). Earthquake response of liquid storage tanks with sliding systems. Journal of Seismology and Earthquake Engineering, Vol. 4, Nos. 23, pp. 51-61.
[18] Kim, M.K. and Lim, Y.M. and Cho, S.Y. and Cho, K.H. and Lee, K.W. (2002). Seismic analysis of base-isolated liquid storage tanks using the BEFE- BE coupling technique. Soil Dynamics and Earthquake Engineering, Vol. 22, Nos. 9-12, pp. 1151-1158.
[19] Moslemi, M. (2011). Seismic response of Ground cylindrical and elevated conical reinforced concrete tanks (Doctoral dissertation). Retrieved from http://digitalcommons.ryerson.ca/
[20] Waghmare P.B. and  Pajgade, P.S. and Kanhe, N.M. (2013). Seismic response of isolated liquid storage tanks with elastomeric bearing. Int J Appl Innovation Eng Manage. 2(2).February.
[21] Naeim, F. and Kelly, J.M. (1999). Design of seismic isolated structures from theory to practice. New York, INC: John Wiley & Sons.
[22] Shrimali, M.K, Jangid, R.S. (2002). Non-linear seismic response of base-isolated liquid storage tanks to bi-directional excitation. Nuclear Engineering and Design, 217, 1-20.
[23] Shrimali, M.K. and Jangid, R.S. )2003(. The seismic response of elevated liquid storage tanks isolated by lead-rubber bearings. Bulletin of the New Zealand Society of Earthquake Engineering, pp. 141-164.
[24] Masoudi M, Eshghi S, Ghafory-Ashtiany M. (2012). Evaluation of response modification factor (R) of elevated concrete tanks. Engineering Structures, 39, 199–209.
[25] Ghaemmaghami, A.R. and Kianoush, M.R. (2010). Effect of wall flexibility on dynamic response of concrete rectangular liquid storage tanks under horizontal and vertical ground motions. J Struct Eng, 136(4):441-51.
[26] Hashemi,, S. and Saadatpour, M.M.and Kianoush, M.R. (2013). Dynamic behavior of flexible rectangular fluid containers. Thin-Walled Structures, 66, 23-38.