تاثیر انعطاف پذیری خاک بر طرح بهینه شبکه قطری با ویژه سازی الگوریتم شاهین ها

نوع مقاله : پژوهشی

نویسندگان

1 عضو هیات علمی دانشکده فنی و مهندسی، دانشگاه خوارزمی

2 دانشجوی کارشناسی ارشد دانشگاه خوارزمی

چکیده

شبکه های قطری از جمله سیستمهای مقاوم جانبی هستند که در سالهایی اخیر کارایی آنها در ساختمانهای بلند بسیار مورد توجه می باشد. پژوهش حاضر به بررسی اثر اندرکنش ایستای خاک از طریق اعمال فنرهای معادل پرداخته و از بهینه یابی ابعادی برای غربالگری شبکه قطری استفاده شده است. در این راستا یکی از الگوریتمهای نوین و موثر فرا ابتکاری به نام بهینه یابی شاهینهای شکاری برای مساله مذکوربا لحاظ شماره مقاطع بعنوان متغیرهای طرح گسسته ویژه سازی گردیده است. سپس طرح های بهینه شبکه قطری نمونه با تابع هدف کاهشی وزن فولاد مصرفی تحت قیود تنش و تغییرمکان آیین نامه در برابر بارگذاری همزمان ثقلی و باد در دو حالت تکیه گاه صلب و انعطاف پذیر بدست آمده اند. در نهایت با بررسی مدلهای حاصل طی تحلیل ظرفیتی، مقایسه شاخصهای مختلف برای شبکه قطری ارائه شده که مزایای و ملزومات تاثیر انعطاف پذیری خاک را نه تنها از دیدگاه کاهش هزینه بلکه طی برآورد شاخصهای رفتاری مذکور نشان می دهند.

کلیدواژه‌ها


عنوان مقاله [English]

Soil flexibility effect on optimal diagrid design utilizing falcon optimization algorithm

نویسندگان [English]

  • Mohsen Shahrouzi 1
  • Neda Khavaninzadeh 2
1 Faculty of Engineering, Kharazmi University,
2 MSc. Student of Earthquake Engineering, Kharazmi university
چکیده [English]

Diagrids as lateral-resistant systems in tall buildings, have received much attention in recent years. Most of previous research works model the structure on rigid foundations. It is while, the soil beneath the foundation has some degree of flexibility that should be modeled. Hence, the present work take into account the static soil-structure interaction in such systems. Therefore, a vertical spring is inserted in the structural model. A finite element program is provided here for analyzing diagrid systems under a number of loading combinations considering both gravitational and lateral wind loading. As the structural behavior depends on the distribution of section profiles among its members, sizing optimization is employed for screening the diagrid designs.

In this regard, falcon optimization algorithm is concerned as a recent meta-heuristic. As FOA is based on just sampling the design space without need to any gradient calculation, it is selected and utilized for structural design. The algorithm is recently developed in 2019 and applied for heat exchanger design. It is inspired by Falcons’ hunting behavior simulated via distinct parts of their flight: 1) logarithmic spiral flight in which the falcon keeps its head straight looking sideways at the prey with maximum visual acuity, and 2) diving toward the prey by binocular vision. The first stage provides exploration while the second models search intensification in such a metaheuristic algorithm. In addition, the phenomena of klepto-parasitism between falcons is modeled to enhance the search.

In order to exactly apply both axial and flexural section properties in such a discrete problem, profile indices are taken design variables. They are to be selected from the practical list of profiles during optimization. Member grouping is also employed to deserve symmetry and practical consideration in the models.

Consequently, diagrid design is fixed minimizing the structural weight under code-based stress and deformation constraints. The designs are distinctly obtained for two cases of rigid and flexible soil-structure connections. Applying the external penalty approach, constraints are checked under simultaneous gravitational and wind loading and satisfied in the final optimal designs. Applying pushover analyses, various measures are studied and compared showing importance of soil-flexibility not only in the optimal costs but also in non-linear structural results.

کلیدواژه‌ها [English]

  • Diagrid
  • Metaheuristic algorithm
  • Sizing Optimization
  • Soil-structure interaction
  • Wind loading