بررسی عددی تاثیر بار انفجاری بر پایداری سدهای خاکی

نوع مقاله : علمی - پژوهشی

نویسندگان

دانشکده فنی و مهندسی، دانشگاه محقق اردبیلی، اردبیل، ایران

چکیده

سدهای خاکی تأثیر بسزایی بر زندگی جوامع اطراف دارند بنابراین ضرورت پایش مستمر در حین ساخت و بهره‌برداری ایمن از این سازه‌ها به هنگام اعمال بارگذاری‌های دینامیکی بخصوص بارهای انفجاری ناشی از اقدامات احتمالی خرابکارانه و آتشکاری همواره مورد توجه بوده است. اثرات ناشی از بارگذاری انفجاری ضمن فرض شرایط تاثیرگذار بر عملکرد سدهای خاکی با استفاده از پارامترهای متعددی قابل سنجش بوده که از مهم‌ترین آنها می‌توان به ابعاد گودال ناشی از انفجار و ضریب پایداری شیب‌های سازه‌ی مذکور اشاره نمود. از این رو در پژوهش حاضر با توجه به تحقیقات صورت گرفته در زمینه‌ی بارگذاری‌ دینامیکی سدهای خاکی، ضمن انتخاب مدل و ویژگی‌های آن، به منظور صحت‌سنجی فرآیند شبیه‌سازی و اعمال بارگذاری دینامیکی، نتایج حل عددی با مقاله مرجع مقایسه گردیده که انطباق قابل قبولی را ارائه میدهد. سپس بارگذاری دینامیکی انفجار در قالب نرم افزار اجزای‌محدود در نقاط معینی از سازه شبیه‌سازی شده و پس از تحلیل، نتایج نشان می‌دهد که با افزایش میزان شارژ انفجاری و افزایش سطح آب مخزن سد و نیز کاهش چگالی مواد تشکیل دهنده‌ی بدنه؛ عمق و ابعاد حفره‌ی ایجاد شده‌ی ناشی از انفجار در تاج سد که بیانگر خرابی موضعی نیز خواهد بود، افزایش می‌یابد. در نهایت برای بررسی پایداری دینامیکی شیب‌ها، نتایج به صورت داده‌های جابجایی-زمان در عمق مشخص در زیر نقاط انفجاری، از نرم‌افزار اجزای‌محدود به نرم‌افزار تحلیل پایداری شیب‌ها منتقل شده و مدل تحت تحلیل شبه استاتیکی و دینامیکی و در نهایت تحلیل پایداری قرار می‌گیرد. نتایج بیانگر این موضوع است که تحت شارژ انفجاری 800 کیلوگرم با موقعیت بارگذاری مشخص، ضریب اطمینان پایداری شیب‌ها از میزان ضریب اطمینان معرفی شده توسط نشریه 624 بیشتر بوده که مبین عدم آسیب‌دیدگی جدی و عدم ناپایداری سازه‌ی سد می باشد

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical study of the effect of explosive load on the stability of earth dams

نویسندگان [English]

  • Amin Gholizad
  • soheil sarparast sadat
Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
چکیده [English]

Earthen dams have a significant impact on the lives of surrounding communities, so the need for continuous monitoring during the construction and safe operation of these structures when applying dynamic loads, especially explosive loads due to possible sabotage and firefighting has always been considered. The effects of explosive loading, assuming the conditions affecting the performance of earth dams, can be measured using several parameters, the most important of which are the dimensions of the pit caused by the explosion and the stability coefficient of the slopes of the structure. Therefore, in the present study, according to the researches done in the field of dynamic loading of earth dams, while selecting the model and its characteristics, in order to validate the simulation process and apply dynamic loading, the results of numerical solution with the article A reference is compared that provides acceptable consistency. Then the dynamic loading of the explosion in the form of finite element software is simulated in certain parts of the structure and after analysis, the results show that by increasing the explosive charge and increasing the water level of the dam reservoir and also reducing the density of constituents Of the body; The depth and dimensions of the hole created by the explosion in the crown of the dam will increase, which will also indicate local damage. Finally, to investigate the dynamic stability of the slopes, the results are transferred from finite element software to the slope stability analysis software, and the model under pseudo-analysis Static and dynamic, and finally stability analysis. The results indicate that under an explosive charge of 800 kg , the reliability coefficient of slope stability is higher than the reliability coefficient introduced by the publication 624, which indicates no serious damage and instability of the dam structure

کلیدواژه‌ها [English]

  • Earth Dam
  • Blast Load
  • Finite Element Method
  • Dynamic Analysis
  • Stability Analysis
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