بهینه‌سازی ظرفیت باربری و نشست تفاضلی گروه شمع قائم با استفاده از الگوریتم ژنتیک

نوع مقاله : علمی - پژوهشی

نویسندگان

1 استادیار، دانشکده مهندسی عمران، دانشگاه تربیت دبیر شهید رجایی، تهران، ایران

2 کارشناس ارشد مهندسی ژئوتکنیک، دانشکده مهندسی عمران، دانشگاه تربیت دبیر شهید رجایی، تهران، ایران

چکیده

طول شمع‌ها در اغلب گروه‌های شمع‌، بصورت مساوی انتخاب و اجرا می‌شوند در حالیکه اندرکنش بین شمع‌ها نشان می‌دهد که این روش و شکل اجرا، همواره بهینه‌ترین و بهترین گزینه ممکن جهت دستیابی به ظرفیت باربری مناسب با کمترین نشست و جابجایی نمی‌باشد. در این مقاله بهینه‌سازی ظرفیت باربری، سختی محوری و نشست تفاضلی کلاهک در یک گروه شمع، با هندسه و طول متفاوت مورد ارزیابی قرار می‌گیرد. روش بهینه‌سازی مورد استفاده در این تحقیق برای یک گروه شمع با ظرفیت باربری اصطکاکی قابل کاربرد است. معیار بهینه‌سازی در این پژوهش، کاهش حجم بتن مصرفی در اجرای کلاهک و گروه شمع است که برای مقاصد اقتصادی و زیست محیطی می‌تواند بسیار مفید باشد چرا که با مصرف مصالح کمتر و به دنبال آن هزینه کمتر، گروه شمع می‌تواند عملکرد مورد انتظار را از نظر ظرفیت باربری و نشست نشان ‌دهد. در این مقاله گروه شمع 5×5 با آرایش مربعی و سطری مورد بررسی قرار می‌گیرند و بهینه‌سازی با بهره‌گیری از الگوریتم تکاملی ژنتیک انجام شده و برای تحلیل ظرفیت باربری شمع‌ها از نرم‌افزار اجزاء محدود Fb-Pier استفاده شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Optimization of bearing capacity and unsymmetrical settlement of vertical pile group using genetic algorithm

نویسندگان [English]

  • Saeed Ghaffarpour Jahromi 1
  • Abdollah Hoseini 2
1 Assistant Professor, Department of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran
2 MSc of Geotechnical Engineering, Department of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran
چکیده [English]

Capacity of pile group is the summation of the individual piles capacity with influence of spacing between the piles. Pile groups usually have the same length, so if the spacing between piles is too close, the zones of stress around the pile will overlap and the ultimate load of the group is less than the sum of the individual pile capacities especially in the case of friction piles, where the efficiency of pile group is much less. In this research the optimization of bearing capacity and unsymmetrical settlement of cap in the vertical pile group using genetic algorithm were studied. Friction pile in granular soil, with different length and arrangement were investigated to find the best performance of the group for the axial stiffness, bearing capacity and unsymmetrical settlement. The criterion of optimization is the volume of concrete needs for piles and cap. Two patterns of 5×5 pile groups (row variation and squared variation) are studied in this research. The analysis of pile group to find bearing capacity was conducted using the finite element software (Fb-pier) and for optimization used evolutionary genetic algorithm method.

کلیدواژه‌ها [English]

  • Pile group
  • optimization
  • Efficiency of pile group
  • Overall stiffness
  • Unsymmetrical settlement
  • Evolutionary genetic algorithm
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