تحلیل عددی اثر لایه‌های خاکی در جلوگیری از انتقال انرژی مکانیکی امواج ضربه‌ای سطحی در زمین با روش المان محدود

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار؛ مجتمع دانشگاهی پدافندغیرعامل، دانشگاه صنعتی مالک اشتر

2 دانش آموخته کارشناسی ارشد؛ عمران-زلزله، دانشگاه بین المللی امام خمینی(ره)

10.22044/tuse.2022.11548.1443

چکیده

امروزه اهمیت استفاده از سازه‌‌های زیرزمینی برای حفاظت از زیرساخت‌های ملی حیاتی و حساس مانند تونل‌های قطار شهری، تأسیسات زیرزمینی شهری، پناهگاه‌ها بر هیچ‌کسی پوشیده نیست. در تحقیق حاضر، ضمن بررسی مطالعات گذشته بر روی نحوه طراحی سازه‌های امن زیرزمینی، با استفاده از مدلسازی عددی، رفتار سازه‌های زیرزمینی در برابر بار ضربه‌ای مورد بررسی قرارگرفته است تا طرحی ارائه شود که با استفاده از خواص محیط دربرگیرنده این‌گونه سازه‌ها، اثر ضربه انتقال‌یافته در محیط بر روی سازة زیرزمینی کاهش داده شود. در این راستا، مدل‌سازی چیدمان خاک تک‌لایه، دولایه و سه لایه و همچنین  لایه‌های ترکیبی از خاک و سنگ، در نرم‌افزار المان محدود ABAQUS انجام‌شده است. بیشینه فشار ناشی از بار ضربه‌ای، در مدل‌های مختلف مورد مقایسه و درنهایت با مقایسه نتایج مدل‌های بکار گرفته‌شده در این مطالعه نشان داده شد که ترتیب چیدمان لایه در خاک‌ها در کاهش بیشینه فشار حاصل از بارگذاری ضربه‌ای مؤثر است، به صورتی که به بیشترین میزان دمپ موج ضربه‌ای زمانی حاصل‌شده که لایه سنگی با بیشترین درجه هوازدگی و یا خاک ماسه‌ای (مشابه خاک تیپ 2 در آئین‌نامه TM5-855) در نزدیک‌ترین موقعیت نسبت به سازة زیرزمینی موردنظر قرارگرفته باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical analysis of the effect of soil layers to prevent the mechanical energy transfer of surface shock waves on the ground using finite elements method

نویسندگان [English]

  • M. Y. Radan Koohpaee 1
  • Seyed A. Hosseini 1
  • A. Moghaddam 2
1 Faculty Member of Passive Defense, Malek Ashtar University of Technology, Tehran.
2 Researcher, Malek Ashtar University of Technology
چکیده [English]

Today, the importance of using Underground structures to protect vital and sensitive national infrastructure such as urban train tunnels, strategic item storage centers, urban underground facilities, shelters, as well as military uses is not hidden from anyone. One of these important loads in terms of intensity and time is impact and seismic loading. Due to the fact that the environment around the underground structures is rock and soil environment, so it is necessary to achieve a good result in reducing the effect of mechanical waves on these spaces, to ensure sufficient reduction of the environment. One of these important loads in terms of intensity and time is impact and seismic loading. On the other hand, natural phenomena such as gas explosion or fire can also be easily incorporated into the structure. These are enough reasons to pay more attention to the science of rebuilding structures against different loads on them. The importance of protecting these spaces increases when they have strategic applications. Therefore, in locating and designing them, it should be noted that they must have sufficient resistance to impact loading In order to achieve a plan that by using the properties of the environment including such spaces, the effect of the impact transmitted in the environment on the underground space can be reduced. Therefore, in the past few years, this software has attracted the attention of many researchers. Finite element modeling and analysis was performed with the commercial software package ABAQUS. The package was selected due to its diverse library of material behavior models and ease of Explicit/Implicit solution procedures. In this paper, impact loading on Underground structures is numerically modeled using the Coupled-Eulerian-Lagrangian (CEL) method in the ABAQUS software. In this regard, modeling of single-layer, two-layer and three-layer soil arrangement, as well as a combination of soil and stone layers, has been done in ABAQUS finite element software. The maximum pressure due to impact load has been compared in different models and finally, by comparing the results of the models used in this study, it shows that the arrangement of the layer in the soils is effective in reducing the maximum pressure due to impact load, So that the maximum amount of shock wave damping is achieved when the rock layer with the highest degree of weathering, or sandy soil (similar to type 2 soil in Regulation TM5-855) is in the closest position to the desired underground space.

کلیدواژه‌ها [English]

  • impact loading
  • Numerical Modeling
  • Soil protective layers
  • Underground structure
Ahmad, S., & Al-Hussaini, T. (1991). Simplified design for vibration screening by open and in-filled trenches. Journal of geotechnical engineering, 117(1), 67-88.
Baziar, M., Salehzadeh, H., Kazemi, M., & Rabeti Moghadam, M. (2014). Centrifuge Modeling of an Underground Structure Subjected to Blast Loading. Underground Structure.
Buonsanti, M., Leonardi, G., & Scopelliti, F. (2011). 3-D Simulation of shock waves generated by dense explosive in shell structures. Procedia Engineering.
Choi, S., Wang, J., Munfakh, G., & Dwyre, E. (2006). 3D nonlinear blast model analysis for underground structures. In GeoCongress. Geotechnical Engineering in the Information Technology, (pp. 1-6).
Cimo, R. (2007). Analytical modeling to predict bridge performance under blast loading. University of Delaware.
Davies, M. (1994). Dynamic soil structure interaction resulting from blast loading In Centrifuge. Balkema Rotterdam, Vol. 94, pp. 319-324.
De, A. (2012). Numerical simulation of surface explosions over dry,cohesionless soil. Computers and Geotechnics, 43, 72-79.
De, A.; Morgante, A.N.;. (2013). Mitigation of blast effects on underground structure using compressible porous foam barriers. In Poromechanics V: Proceedings of the Fifth Biot Conference on Poromechanics, pp. 971-980.
Duffy, M. (1983). Tunnels: Planning, design, construction. vols. 1 & 2: by TM Megaw and JV Bartlett, Ellis Horwood, Chichester, Vol. 1: ISBN 0-85312-223-7, 284 pages,.
Feldgun, V., Karinski, Y., & Yankelevsky, D. (2014). The effect of an explosion in a tunnel on a neighboring buried structure. Tunnelling and Underground Space Technology, 44, pp.42-55.
Gui, M., & Chien, M. (2006). Blast-resistant analysis for a tunnel passing beneath Taipei Shongsan airport–a parametric study. Geotechnical & Geological Engineering, 24(2), 227-248.
Jayasinghe, L., Thambiratnam, D., Perera, N., & Jayasooriya, R. (2014). Effect of soil properties on the response of pile to underground explosion. Structural Engineering International, 24(3), 361-370.
Johnson, G. (1983). A constitutive model and data for materials subjected to large strains, high strain rates, and high temperatures. Proc. 7th Inf. Sympo. Ballistics, 541-547.
Khan, S., Chakraborty, T., & Matsagar, V. (2016). Parametric sensitivity analysis and uncertainty quantification for cast iron–lined tunnels embedded in soil and rock under internal blast loading. Journal of Performance of Constructed Facilities, 30(6), 0.
Larcher, M., & Casadei, F. (2010). Explosions in complex geometries a coMParison of several approaches. International journal of protective structures, 1(2), 169-195.
Lee, J., & Fenves, G. (1998). Plastic-damage model for cyclic loading of concrete structures. Journal of engineering mechanics.
Li, J., Li, H., Ma, G., & Zhou, Y. (2013). Assessment of underground tunnel stability to adjacent tunnel explosion. Tunnelling and Underground Space Technology, 35, pp.227-234.
Mussa, M., Mutalib, A., Hamid, R., Naidu, S., Radzi, N., & Abedini, M. (2017). Assessment of damage to an underground box tunnel by a surface explosion. Tunnelling and Underground Space Technology.
Suazo, G., & Villavicencio, G. (2018). Numerical simulation of the blast response of cemented paste backfilled stopes. Computers and Geotechnics.
Tiwari, R.; Chakraborty, T.; Matsagar, V. (2016). Dynamic analysis of tunnel in weathered rock subjected to internal blast loading. Rock Mechanics and Rock Engineering, 49(11), 4441-4458.
Tiwari, R.; Chakraborty, T.; Matsagar, V. (2017). Dynamic analysis of tunnel in soil subjected to internal blast loading. Geotechnical and Geological Engineering, 35(4), 1491-1512.
TM5-855-1. (1986). Fundamentals of protective design for conventional weapons. US. Department of the Army.
UFC 3-340-02. (2008). Structures to Resist the Effects of Accidental Explosions. Unified Facilities Criteria .
Veyera, G., & Ross, C. (1995). High strain rate testing of unsaturated sands using a split-Hopkinson pressure bar.