بررسی پارامتریک دیوار خاک مسلح ژئوسنتتیکی قرار گرفته بر روی بستر تراکم پذیر

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی عمران، دانشکده مهندسی عمران و معماری، دانشگاه ملایر، ملایر، ایران

چکیده

مطالعات زیادی بر روی دیوار خاک مسلح ژئوسنتتیکی با فرض صلب بودن بستر صورت گرفته است، اما رفتار این سیستم و بررسی اجزاء آن به هنگام تراکم پذیر بودن و یا سست بودن خاک بستر کمتر مورد توجه قرار گرفته است. تحقیق حاضر به بررسی اثر پارامترهای تاثیرگذار )شامل زاویه ی نمای دیوار خاک مسلح نسبت به راستای قائم، نوع اتصال مسلح کنند ه به دیوار، شرایط پنجه‌ی دیوار، طول مسلح-کننده و فاصله‌ی عمودی مسلح کننده‎ها(  بر رفتار دیوار خاک مسلح قرار گرفته بر روی بستر تراکم پذیر، به روش اجزاء محدود می‌پردازد. همچنین رفتار دیوار تحت شرایط پایان ساخت دیوار و نیز بارگذاری سربار مورد بررسی قرار گرفته است. نتایج تحقیق نشان داد پارامتر-هایی که بیشترین تاثیر را به هنگام ضعیف شدن بستر بر رفتار دیوار خاک مسلح داشتند، زاویه‌ی نمای دیوار، فاصله‌ی عمودی بین مسلح- کننده ها و شرایط پنجه‌ی دیوار می‌باشند. کم نمودن فاصله‌ی مسلح کننده ها و افزایش زاویه ی نمای دیوار موجب کاهش قابل توجه جابجایی جانبی دیوار و بار بیشینه‌ی مسلح کننده‌ها می‌گردد. همچنین طبق نتایج در بستر با خاک تراکم پذیر، نوع اتصال مسلح کننده و طول مسلح کننده تاثیر محسوسی بر بهبود رفتار دیوار، بجز در حالتی که دیوار بر روی بستر ضعیف قرار گرفته است، از خود نشان ندادند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Parametric Investigation of Geosynthetics Reinforced Soil Wall Seated on Compressible Bed

نویسندگان [English]

  • V. Ghiasi
  • A. Farzan
Civil Engineering Department, Malayer University, Hamedan, Iran
چکیده [English]

The superiority of the geosynthetic reinforced soil wall to another reinforced soil systems, is led to the increasing expansion. So far many studied have been conducted on geosynthetics reinforced soil walls, with assuming rigid bed. But the behavior of this system and mechanism of it components has less been considered when the bed is compressible or loose. The present study investigated the effect of effective parameters (i.e., facing inclination, connection type of geogrids to the facing, toe condition, length of reinforcement and vertical distance of reinforcements) on the behavior of reinforced soil wall seated on compressible bed, using finite element method. Also the behavior of the wall under conditions of end of construction and surcharge loading has been investigated. The results showed that the parameters that had the greatest effect on the behavior of the reinforced soil wall during the weakening of the bed, is facing inclination, vertical distance between reinforcements and toe condition. Decreasing vertical distance of reinforcements and increasing facing inclination, has led to significantly decrease in horizontal displacement of wall and maximum reinforcement load. Also according to the results, the bed with compressible soil, the type of connection of reinforcement and length of reinforcement did not show a significant effect on the improvement of the wall’s behavior, except when the wall was placed on a loose bed.

کلیدواژه‌ها [English]

  • Reinforced soil wall
  • Numerical modeling
  • Geo-grid
  • Facing inclination
  • Toe Conditions
[1] K. Kazimierowicz-Frankowska, A case study of a geosynthetic reinforced wall with wrap-around facing, Geotextiles and Geomembranes, 23(1) (2005) 107-115.
[2] C. Yoo, S.-B. Kim, Performance of a two-tier geosynthetic reinforced segmental retaining wall under a surcharge load: full-scale load test and 3D finite element analysis, Geotextiles and Geomembranes, 26(6) (2008) 460-472.
[3] G. Yang, B. Zhang, P. Lv, Q. Zhou, Behaviour of geogrid reinforced soil retaining wall with concrete-rigid facing, Geotextiles and Geomembranes, 27(5) (2009) 350-356.
[4] M. Ehrlich, S. Mirmoradi, Evaluation of the effects of facing stiffness and toe resistance on the behavior of GRS walls, Geotextiles and Geomembranes, 40 (2013) 28-36.
[5] S. Mirmoradi, M. Ehrlich, Effects of facing, reinforcement stiffness, toe resistance, and height on reinforced walls, Geotextiles and Geomembranes, 45(1) (2017) 67-76.
[6] S. Mirmoradi, M. Ehrlich, Evaluation of the effect of toe restraint on GRS walls, Transportation Geotechnics, 8 (2016) 35-44.
[7] S. Mirmoradi, M. Ehrlich, C. Dieguez, Evaluation of the combined effect of toe resistance and facing inclination on the behavior of GRS walls, Geotextiles and Geomembranes, 44(3) (2016) 287-294.
[8] O. Rahmouni, A. Mabrouki, D. Benmeddour, M. Mellas, A numerical investigation into the behavior of geosynthetic-reinforced soil segmental retaining walls, International Journal of Geotechnical Engineering, 10(5) (2016) 435-444.
[9] S. Mirmoradi, M. Ehrlich, Numerical evaluation of the behavior of GRS walls with segmental block facing under working stress conditions, Journal of Geotechnical and Geoenvironmental Engineering, 141(3) (2014) 401-409.
[10] A. Abdelouhab, D. Dias, N. Freitag, Numerical analysis of the behaviour of mechanically stabilized earth walls reinforced with different types of strips, Geotextiles and Geomembranes, 29(2) (2011) 116-129.
[11] H. Ling, D. Leshchinsky, Finite element parametric study of the behavior of segmental block reinforced-soil retaining walls, Geosynthetics International, 10(3) (2003) 77-94.
[12] Y. Yu, I.P. Damians, R.J. Bathurst, Influence of choice of FLAC and PLAXIS interface models on reinforced soil-structure interactions, Computers and Geotechnics, 65 (2015) 164-174.
[13] R. Brinkgreve, Plaxis: Finite Element Code for Soil and Rock Analyses: 2D-Version 8:[user’s Guide], Balkema, 2006.
[14] R.J. Bathurst, D. Walters, N. Vlachopoulos, P. Burgess, T. Allen, Full scale testing of geosynthetic reinforced walls, in: Advances in transportation and geoenvironmental systems using geosynthetics, 2000, pp. 201-217.
[15] K. Hatami, R.J. Bathurst, Development and verification of a numerical model for the analysis of geosynthetic-reinforced soil segmental walls under working stress conditions, Canadian Geotechnical Journal, 42(4) (2005) 1066-1085.
[16] K. Hatami, R.J. Bathurst, Numerical model for reinforced soil segmental walls under surcharge loading, Journal of Geotechnical and Geoenvironmental engineering, 132(6) (2006) 673-684.
[18] N. Janbu, Soil compressibility as determined by oedometer and triaxial tests, in: Proceedings of the European conference on soil mechanics and foundation engineering, 1963, pp. 19-25.
[19] FHWA, Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes, Volume I, (2010).