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مطالعه عددی و آزمایشگاهی بر روی رفتار لرزه‌ای خاک میخ کوبی شده به منظور ارائه ضریب شبه استاتیکی بر اساس سطوح عملکرد | ||
| نشریه مهندسی عمران امیرکبیر | ||
| مقاله 16، دوره 50، شماره 1، فروردین و اردیبهشت 1397، صفحه 189-210 اصل مقاله (4.75 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/ceej.2017.11737.5068 | ||
| نویسنده | ||
| مجید یزدان دوست* | ||
| گروه عمران، دانشکده فنی و مهندسی دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران | ||
| چکیده | ||
| با توجه به گسترش استفاده از روش طراحی بر مبنای عملکرد لرزه‌ای در میان سازه‌های ژئوتکنیکی طی دو دهة اخیر و محروم ماندن سیستم‌های میخ کوبی از این توسعه، در این تحقیق کوشش شده است تا ضریب شبه استاتیکی به عنوان تابعی از پارامترهای اصلی زلزله، ویژگیهای ژئوتکنیکی در قالب شرایط ساختگاهی و سطوح عملکرد دیوار میخ کوبی شده معرفی گردد. به این منظور، با استفاده از آزمایشات میز لرزه بر روی مدل فیزیکی سیستم میخ کوبی به تعیین مرز‌های سطوح عملکرد این سیستم در شرایط لرزه‌ای و هندسی مختلف پرداخته شده است. سپس با تکیه بر نتایج حاصل از مدلسازی عددی سیستم میخ کوبی در قالب تغییر شکلهای ماندگار و تعیین ضریب شبه استاتیکی معادل هر یک از مدلهای‌های عددی مورد مطالعه با استفاده از آنالیزهای تعادل حدی، به ارائة ضریب شبه استاتیکی معادل با سطوح عملکرد پرداخته شده است. نتایج حاصل در قالب تقسیمات ساختگاهی و لرزه‌ای مطابق با آیین‌نامه 2800 ایران و بصورت مجزا ارائه شده است که بیانگر تأثیر چشمگیر نوع ساختگاه و شرایط لرزه‌ای بر انتخاب ضریب شبه استاتیکی معادل با سطوح عملکرد می‌باشد. از سوی دیگر، سطح گسیختگی مشاهده شده در این سیستم یک سطح گسیختگی منحنی‌الخط با نقطة عطف مشخص می باشد به نحوی که مکان هندسی آن به عنوان تابعی از طول میخ‌ها تعریف می‌شود. همچنین، صرف نظر از طول میخ‌های مختلف، مقادیر x/H = 0/5%∆ بعنوان مرز وقوع تغییر شکلهای پلاستیک و مقادیر x/H = 3/75%∆ به عنوان مرز تشکیل گوه گسیختگی و وقوع تخریب برای سیستم میخ کوبی مشاهده شد. | ||
| کلیدواژه‌ها | ||
| خاک میخ کوبی شده؛ عملکرد لرزه‌ای؛ ضریب شبه استاتیکی؛ سطوح عملکرد؛ مکانیزم گسیختگی | ||
| موضوعات | ||
| پایداری شیروانی های خاکی؛ خاک مسلح؛ دینامیک خاک؛ ژئو تکنیک لرزه ای | ||
| عنوان مقاله [English] | ||
| Numerical and Experimental Study on Seismic Behavior of Soil-Nailed Walls to Introduce the Pseudo Static Coefficient Based on Performance Levels | ||
| نویسندگان [English] | ||
| M. Yazdandoust | ||
| Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran | ||
| چکیده [English] | ||
| This study, tries to suggest a design method based on displacement using experimental and numerical modeling in soil nailed walls. In this case, dynamic loading characteristics, geometrical characteristics of reinforced soil mass and type of the site are considered to introduce the pseudo static coefficient as a function of seismic performance level and dynamic loading characteristics. For this purpose, the influence of dynamic loading characteristics, reinforcement length, height of reinforced system and type of the site are investigated on seismic behavior of soil nailed wall by numerical analysis. Furthermore, the performance levels of this structure were determined by experimental studies of shaking table tests. The results illustrate that the seismic response of this type of wall is highly dependent to cumulative absolute velocity, maximum acceleration, height and reinforcement length. The results also indicate that the use of coefficients in this study leads to most efficient designs in comparison with other methods which are generally suggested in codes that are usually based on limit-equilibrium concept. The outputs show the over-estimation of equilibrium design methods in comparison with proposed displacement based methods here. The pattern of the observed failure mechanisms included a moving block and a parabolic failure surface with certain inflection point. Also, irrespective of different nail lengths, a range of Δx/H = 0.5 % as a transitional level from quasi-elastic to plastic state and based on starting the development of active wedge failure, a range of Δx/H = 3.75% as a transitional level from plastic to failure state were determined. | ||
| کلیدواژه‌ها [English] | ||
| Soil-Nailed Wall, seismic performance, Pseudo Static Coefficient, Seismic Levels, Dynamic Failure Mechanism | ||
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سایر فایل های مرتبط با مقاله
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| مراجع | ||
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[1] GEOGUIDE 7, Guide to Soil NAIL Design and Construction, The Government of the Hong Kong Special Administrative Region, 2008. [2] FHWA-NHI-14-007, Soil Nail Walls Reference Manual, Federal Highway Administration and National Highway Institute, Washington DC, 2015. [3] L.J. Su, J.H. Yin, W.H. Zhou, Influences of overburden pressure and soil dilation on soil nail pull-out resistance, Computers and Geotechnics Journal, 37(2) (2010) 555-564. [4] S.A. Tan, P.H. Ooi, T.S. Park, W.L. Cheang, Rapid Pullout Test of Soil Nail, Journal of Geotechnical and Geoenvironmental Engineering, 134(9) (2008) 1327-1338. [5] M. Choukeir, I. Juran, S. Hanna, Seismic Design of Reinforced- Earth and Soil-Nailed Structures, Ground Improvement, 1(1997) 223-238. [6] I. Juran, G. Baudrand, K. Farrang, V. Elias, Kinematical Limit Analysis for Design of Soil-Nailed Structures, Journal of Geotechnical Engineering, 116(1) (1990) 54-72. [7] M.R. Tufenkjian, M. Vucetic, Dynamic failure Mechanism of Soil- Nailed Excavation Models in Centrifuge, Journal of Geotechnical and Geoenvironmental Engineering, 126(3) (2000) 227-235. [8] Y. Hong, R. Chen, C. Wu, J. Chen, Shaking Table Test and Stability Analysis of Steep Nailed Slopes, Canadian Geotechnical Journal, 42(2005) 1264- 1279. [9] G.L. Sivakumar Babu, V. Pratap Singh, Numerical Analysis of Performance of Soil Nail Walls in Seismic Conditions, ISET Journal of Earthquake Technology, 45(1-2) (2008) 31-40. [10] D. Giri, A. Sengupta, Dynamic Behavior of Small Scale Nailed Soil Slopes, Geotechnical and Geological Engineering, 27(2009) 678-698. [11] A. Sengupta, D. Giri, Behavior of nailed steep slopes in laboratory shake table tests, in: Proceedings of the Fifth International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics, San Diego, California, 2010. [12] L.P. Wang, G. Zhang, J.M. Zhang, Nail reinforcement mechanism of cohesive soil slopes under earthquake conditions, Soils and Foundations, 50 (4) (2010) 459-469. [13] S. He, C. Ouyang, Y. Luo, Seismic stability analysis of soil nail reinforced slope using kinematic approach of limit analysis, Environmental Earth Sciences, 66(1) (2012) 319-326. [14] F. Tatsuoka, H. Mun˜ oz, T. Kuroda, H. Nishikiori, R. Soma, T. Kiyota, M. Tateyama, K. Watanabe, Stability of existing bridges improved by structural integration and nailing, Soils and Foundations, 52(3) (2012) 430-448. [15] S. Majidian, A. Komakpanah, 2D numerical modelling of soil-nailed structures for seismic improvement, Geomechanics and Engineering Journal, 5(1) (2013) 37-55. [16] S. Zamiran, H. Ghojavand, H. Saba, Numerical Analysis of Soil Nail Walls under Seismic Condition in 3D Form Excavations, Applied Mechanics and Materials, 204-208(2012) 2671-2676. [17] V.M. Rotte, B.V.S. Viswanadham, Centrifuge and Numerical Model Studies on the Behaviour of Soil-Nailed Slopes with and without Slope Facing, in: Proceedings of the International Conference on Tunneling and Underground Construction, ASCE, China, 2014, pp. 581-591. [18] S.L. Kramer, Performance-based design methodologies for geotechnical earthquake engineering, Bulletin of Earthquake Engineering, 12(3) (2013) 1049-1070. [19] S.L. Kramer, C. Valdez, B. Blanchette, J.W. Baker, Performance-Based Design Factors for Pile Foundations, PEER Report Pacific Earthquake Engineering Research Center College of Engineering University of California, Berkeley, 2014. [20] C. Ledezma, J. Bray, Probabilistic Performance-Based Procedure to Evaluate Pile Foundations at Sites with Liquefaction-Induced Lateral Displacement, Journal of Geotechnical and Geoenvironmental Engineering 136(3) (2010) 464-476. [21] Y. Wu, S. Prakash, Design Charts for Retaining Walls in Seismic Areas, GeoFlorida 2010, pp. 2973-2981. [22] A.L. Simonelli, P. Penna, Performance-based design of gravity retaining walls under seismic actions, Eurocode 8 Perspectives from the Italian Standpoint Workshop, Doppiavoce, Napoli, Italy, 2009, pp. 277-289. [23] B. Doran, J. Shen, B. Akbas, Seismic Evaluation of Existing Wharf Structures Subjected to Earthquake Excitation: Case Study, Earthquake Spectra, 31(2) (2015) 1177-1194. [24] J. Koseki, S. Nakajima, M. Tateyama, M. Shinoda, Seismic performance of geosynthetic-reinforced soil retaining walls and their performance-based design in Japan, in: Proceedings of the international conference on performance-based design in earthquake geotechnical engineering, IS-Tokyo, 2009, pp. 149-162. [25] C.C. Huang, S.H. Wu, H.J. Wu, Seismic displacement criterion for soil retaining walls based on soil strength mobilization, Geotechnical and Geoenvironmental Engineering, 135(1) (2009) 74-83. [26] M. Yazdandoust, Laboratorial and Numerical Studies on Reinforced Soil and Earth whit Steel Elements, Ph.D. Thesis, Tarbiat Modares Univercity, Tehran, Iran, 2013. [27] R. J. Bathurst, K. Hatami, Influence of Reinforcement Stiffness, Length and Base Condition on Seismic Response of Geosynthetic Reinforced Soil Wall, in: Proceedings of the 6th International Conference on Geosynthetics, USA, 1998, pp. 613-616. [28] No S. 2800, Iranian Code of Practice for Seismic Resistant Design of Buildings, Fourth Revision, Building and Housing Research Center, Tehran, 2014. [29] K. Ishihara, A.M. Asal, Dynamic behavior of soils, soil amplification and soil structure interaction, final report for working group d, UNDP/UNESCO project on earthquake risk reduction in Balkan region, 1982. [30] M.K. Jafari, A. Shafiee, A. Ramzkhah, Dynamic properties of the fine grained soils in south of Tehran, Journal of Seismology and Earthquake Engineering, 4(2002) 25-35. [31] H.B. Seed, T.R. Wong, I.M. Idriss, K. Tokimatsu, Moduli and damping factors for dynamic analyses of cohesionless soils, Journal of Geotechnical Engineering, 112(11) (1986) 1016-1032. [32] E.Y. Sharif, A.A. Al Bis, M.K. Harb, An Application of Geophysical Techniques for Determining Dynamic Properties of the Ground in Dubailand Area, UAE.”, Arab Center for Engineering Studies, 2008. [33] J. Chai, J.P. Carter, Deformation Analysis in Soft Ground Improvement, Springer Science & Business Media, 2011. [34] S.L. Kramer, Geotechnical Earthquake Engineering, Prentice Hall, 1996. [35] FLAC Manual , Ver. 5.0, Itasca, USA, 2005. [36] L.J. Su, J.H. Yin, W.H. Zhou, Influences of overburden pressure and soil dilation on soil nail pull-out resistance, Computers and Geotechnics, 37(2010) 555-564. [37] NCHRP REPORT 701, Proposed Specifications for LRFD Soil-Nailing Design and Construction, in: National Cooperative Highway Research Program, 2011. [38] PIANC, Seismic design guidelines for port structures, International Navigation Association, Working Group No. 34 of the Maritime Navigation Commission, Tokyo, 2001. [39] C.C. Huang, J.C. Horng, W.J. Chang, J.S. Chiou, C.H. Chen, Dynamic behavior of reinforced walls e Horizontal displacement response, Geotextiles and Geomembranes, 29(2011) 257-267. [40] D.M. Wood, Geotechnical Modeling, Version 2.2, 2014 (electronic copy). | ||
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