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اثر بارگذاری ترکیبی بر ظرفیت باربری پی نواری مستقر بر خاک دو لایه رسی مجاور شیب مسلح با ژئوگرید | ||
| نشریه مهندسی عمران امیرکبیر | ||
| مقاله 6، دوره 55، شماره 9، آذر 1402، صفحه 1825-1844 اصل مقاله (2.15 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/ceej.2023.21741.7812 | ||
| نویسندگان | ||
| میثم محبوبی نیازمندی* 1؛ سهراب میراثی2؛ مهدی هاشمی جوکار3؛ محمد مومنی2 | ||
| 1دانشکده مهندسی عمران و محیط زیست، دانشگاه صنعتی شیراز، شیراز، ایران | ||
| 2گروه مهندسی عمران، واحد شهر کرد، دانشگاه آزاد اسلامی، شهر کرد، ایران | ||
| 3عضو اصلی کمیسیون تخصصی ژئوتکنیک، سازمان نظام مهندسی ساختمان، تهران، ایران | ||
| چکیده | ||
| هدف مقاله حاضر تعیین ظرفیت باربری زهکشینشده پیهای نواری مستقر بر خاکهای دولایه رسی در مجاورت یک شیب مسلحشده با ژئوگرید تحت اثر بارگذاریهای ترکیبی با اعمال بارهای افقی (H)، قائم (V) و لنگر خمشی (M) میباشد. به همین منظور با مدلسازی المان محدود در نرمافزار آباکوس و انجام تحلیل برمبنای روش بار-جابجایی کنترل شده، پوشهای گسیختگی و مکانیزم گسیختگی خاک زیر پی در فضاهای بارگذاری V-H، V-M و V-H-M تعیین شد. نتایج حاصله در دو حالت شیبهای فاقد تسلیح و مسلحشده با لایههای ژئوگرید و با انجام مطالعات پارامتریک درخصوص اثر تغییرات نسبتهای مقاومت زهکشینشده لایههای خاک رسی (Cu1/Cu2) و نسبت ضخامت لایه رسی اول به عرض پی نواری (H1/B) مقایسه شد. نتایج نشان داد که با افزایش Cu1/Cu2 در بارگذاری V-H، ظرفیت باربری قائم افزایش یافته که ناشی از افزایش چسبندگی زهکشینشده لایه اول است. همچنین در بارگذاریهای ترکیبی V-H و V-M در حالتی که تنها بارگذاری قائم وجود داشته باشد، حجم بیشتری از خاک دچار گسیختگی میشود. همچنین نتایج نشان داد که تسلیح شیب با ژئوگرید بهترتیب باعث افزایش 31 و 35 درصدی ظرفیت باربری قائم و ظرفیت لنگر خمشی پی میگردد. بطور کلی یافتههای این مطالعه بینش جدیدی را از مکانیزم گسیختگی پیهای نواری مستقر بر خاکهای دولایه رسی در مجاورت شیبهای مسلحشده با ژئوگرید تحت اثر بارگذاریهای ترکیبی فراهم مینماید. | ||
| کلیدواژهها | ||
| تحلیل المان محدود؛ پی نواری؛ خاک رسی دولایه؛ شیب مسلح با ژئوگرید؛ بارگذاری ترکیبی | ||
| موضوعات | ||
| مکانیک خاک و پی | ||
| عنوان مقاله [English] | ||
| The effect of combined loading on the bearing capacity of strip footings located on two-layered clayey soils adjacent to geogrid-reinforced slopes | ||
| نویسندگان [English] | ||
| Meisam Mahboubi Niazmandi1؛ Sohrab Mirasi2؛ Mehdi Hashemi jokar3؛ Mohammad Momeni2 | ||
| 1Department of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran | ||
| 2Department of Civil Engineering, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran | ||
| 3The main member of the specialized geotechnical commission, the organization of the construction engineering system | ||
| چکیده [English] | ||
| The present paper aims to determine the undrained bearing capacity of strip footings located on two-layered clayey soil in the vicinity of a geogrid-reinforced slope under the effect of combined loading by applying horizontal (H), vertical (V), and bending moment (M) loads. To this aim, by finite element modeling in ABAQUS based on the controlled load-displacement method, the failure envelopes and the failure mechanism of the subsoil of strip footings under the effect of combined loadings were determined in V-H, V-M, and V-H-M loading spaces. The results obtained in two cases of unreinforced and reinforced slopes with geogrids were compared by performing parametric studies regarding the effect of changes in undrained shear strength ratios of clayey layers (Cu1/Cu2) and the ratio of the thickness of the first clay layer to the width of the strip foundation (H1/B). The results showed that by increasing Cu1/Cu2 in V-H loading spaces, the vertical bearing capacity increased, which is caused by the increase in the undrained cohesion of the first layer. Furthermore, in scenarios involving both vertical-horizontal (V-H) and vertical-moment (V-M) load combinations, when subjected solely to vertical loading, a greater volume of soil experienced failure. The results showed that reinforcing the slope with geogrid increases the vertical and the moment bearing capacity by 31 and 35%, respectively. In general, the findings of this study provide new insight into the failure mechanism of strip foundations based on two-layered clayey soils in the vicinity of geogrid-reinforced slopes under the effect of combined loads. | ||
| کلیدواژهها [English] | ||
| Finite element analysis, strip footings, two-layer clayey soil, geogrid-reinforced slope, combined loading | ||
| مراجع | ||
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[1] R. Kimmerling, Geotechnical engineering circular No. 6 shallow foundations, United States. Federal Highway Administration. Office of Bridge Technology, 2002. [2] A.S. Vesić, Analysis of ultimate loads of shallow foundations, Journal of the Soil Mechanics and Foundations Division, 99(1) (1973) 45-73. [3] R. Sharma, Q. Chen, M. Abu-Farsakh, S. Yoon, Analytical modeling of geogrid reinforced soil foundation, Geotextiles and Geomembranes, 27(1) (2009) 63-72. [4] P. Rao, Y. Liu, J. Cui, Bearing capacity of strip footings on two-layered clay under combined loading, Computers and Geotechnics, 69 (2015) 210-218. [5] M. Bransby, G.-J. Yun, The undrained capacity of skirted strip foundations under combined loading, Géotechnique, 59(2) (2009) 115-125. [6] L.C. Hung, S.-R. Kim, Evaluation of undrained bearing capacities of bucket foundations under combined loads, Marine Georesources & Geotechnology, 32(1) (2014) 76-92. [7] S. Alamshahi, N. Hataf, Bearing capacity of strip footings on sand slopes reinforced with geogrid and grid-anchor, Geotextiles and Geomembranes, 27(3) (2009) 217-226. [8] D.T. Bergado, P.V. Long, B.S. Murthy, A case study of geotextile-reinforced embankment on soft ground, Geotextiles and Geomembranes, 20(6) (2002) 343-365. [9] C. Yoo, Laboratory investigation of bearing capacity behavior of strip footing on geogrid-reinforced sand slope, Geotextiles and Geomembranes, 19(5) (2001) 279-298. [10] M.A. El Sawwaf, Behavior of strip footing on geogrid-reinforced sand over a soft clay slope, Geotextiles and Geomembranes, 25(1) (2007) 50-60. [11] M. Ghazavi, A.A. Lavasan, Interference effect of shallow foundations constructed on sand reinforced with geosynthetics, Geotextiles and Geomembranes, 26(5) (2008) 404-415. [12] P. Basudhar, P. Dixit, A. Gharpure, K. Deb, Finite element analysis of geotextile-reinforced sand-bed subjected to strip loading, Geotextiles and Geomembranes, 26(1) (2008) 91-99. [13] G.L. Araújo, E.M. Palmeira, Í.L. Macêdo, Comparisons between predicted and observed behaviour of a geosynthetic reinforced abutment on soft soil, Engineering geology, 147 (2012) 101-113. [14] J. Ko, H. Seo, J.K. Lee, Failure Envelopes for Circular Foundations on Two-Layered Clay under Combined Loading, International Journal of Geomechanics, 22(7) (2022) 04022085. [15] H. Xia, X. Zhou, M. Zhou, F. Niu, X. Zhang, Capacity of caissons in stiff-over-soft clay under combined V–HM loadings, Ocean Engineering, 229 (2021) 109007. [16] B.T. Chua, K.P. Nepal, A new approach to estimate bearing capacity of strip footings on geogrid-stabilised granular layer over clay, Transportation Infrastructure Geotechnology, 10(4) (2023) 569-594. [17] Z. Shen, D. Jin, Q. Pan, H. Yang, S.C. Chian, Effect of soil spatial variability on failure mechanisms and undrained capacities of strip foundations under uniaxial loading, Computers and Geotechnics, 139 (2021) 104387. [18] C. Martin, C. Martin, Physical and numerical modelling of offshore foundations under combined loads, Oxford University, UK, 1994. [19] J. Salençon, A. Pecker, Ultimate bearing capacity of shallow foundations under inclined and eccentric loads. Part I: purely cohesive soil, European journal of mechanics series - A/Solids, 14 (1995) 349-349. [20] H.A. Taiebat, J.P. Carter, Numerical studies of the bearing capacity of shallow foundations on cohesive soil subjected to combined loading, Geotechnique, 50(4) (2000) 409-418. [21] H.A. Taiebat, J.P. Carter, Bearing capacity of strip and circular foundations on undrained clay subjected to eccentric loads, Geotechnique, 52(1) (2002) 61-64. [22] S. Gourvenec, M. Randolph, Effect of strength non-homogeneity on the shape of failure envelopes for combined loading of strip and circular foundations on clay, Géotechnique, 53(6) (2003) 575-586. [23] G.T. Houlsby, A.M. Puzrin, The bearing capacity of a strip footing on clay under combined loading. Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 455 (1983), 893-916. [24] B. Bienen, C. Gaudin, M.J. Cassidy, L. Rausch, O.A. Purwana, H. Krisdani, Numerical modelling of a hybrid skirted foundation under combined loading, Computers and Geotechnics, 45 (2012) 127-139. [25] C. Tang, K.-K. Phoon, K.-C. Toh, Effect of footing width on Nγ and failure envelope of eccentrically and obliquely loaded strip footings on sand, Canadian Geotechnical Journal, 52(6) (2015) 694-707. [26] A. Hentati, M. Selmi, T. Kormi, N.B.H. Ali, Probabilistic HM failure envelopes of strip foundations on spatially variable soil, Computers and Geotechnics, 102 (2018) 66-78. [27] A. Haghighi, P. Hu, J.G. Tom, K. Krabbenhoft, Combined loading of strip footings on sand-over-clay with layers of varying extents, Soils and Foundations, 59(2) (2019) 433-442. [28] M. Bransby, M. Randolph, Combined loading of skirted foundations, Géotechnique, 48(5) (1998) 637-655. [29] S. Helwany, Applied soil mechanics with ABAQUS applications, John Wiley & Sons, 2007. [30] D.S. Simulia, ABAQUS 6.13 User’s manual, Dassault Systems, Providence, RI, 305 (2013) 306. [31] D.M. Potts, L. Zdravković, T.I. Addenbrooke, K.G. Higgins, N. Kovačević, Finite element analysis in geotechnical engineering: application, Thomas Telford London, 2001. [32] T. Sitharam, S. Sireesh, Model studies of embedded circular footing on geogrid-reinforced sand beds, Proceedings of the Institution of Civil Engineers-Ground Improvement, 8(2) (2004) 69-75. [33] A. Lashkari, M. Mahboubi, Use of hyper-elasticity in anisotropic clay plasticity models, Scientia Iranica, 22(5) (2015) 1643-1660. [34] S.W. Perkins, M.Q. Edens, Finite element and distress models for geosynthetic-reinforced pavements, International Journal of Pavement Engineering, 3(4) (2002) 239-250. [35] G. Altay, C. Kayadelen, T. Taşkıran, Y.Z. Kaya, A laboratory study on pull-out resistance of geogrid in clay soil, Measurement, 139 (2019) 301-307. [36] R. Merifield, S. Sloan, H. Yu, Rigorous plasticity solutions for the bearing capacity of two-layered clays, Geotechnique, 49(4) (1999) 471-490. | ||
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