Abstract    The design codes of building are mainly related to the strength of the building and there are no specific codes for the design of building with waffle floors for vibration sensitive equipment. The finite element model, ANSYS, is capable to consider the effects of floor thickness, the size of the bays and stiffness of the columns for analyzing the vibration of the waffle floors and vibration transmission along the waffle floor. Because the finite element analysis is time consuming and it needs enough expertise for modeling, in this study, an approximate relationship is proposed to design the waffle floor based on the comprehensive investigations of different effective parameters in the response of waffle floor and the results obtained from finite element analysis. This proposed relationship comforts the designers of industrial buildings and vibration sensitive equipment to attain a preliminary and appropriate outline to design the waffle floor considering the effective parameters on the floor vibration.

Keywords    Waffle floor, Vibration, Harmonic loading, Finite element

چکیده    آيين­نامه­هاي مهندسي عمران براي طراحي ساختمان­ها، عمدتاً به مقاومت ساختمان براي تحمل بارهاي زلزله و استاتيكي پرداخته و آيين­نامه جامعي براي طراحي ساختمان با كف­ مشبك براي تجهيزات حساس به ارتعاش موجود نمي­باشد. مدل اجزاي محدود ANSYS براي تحليل ارتعاش در مركز كف مشبك و انتقال ارتعاش در امتداد كف مشبك مي­تواند اثر ضخامت كف، اندازه دهانه­ها و سختي ستون­ها را لحاظ كند. با توجه به وقت­گير بودن آناليز در نرم افزار اجزاي محدود و نياز به مهارت كافي براي مدل سازي، در اين مطالعه با بررسي جامع پارامترهاي مختلف موثر در پاسخ كف مشبك به بار هارمونيك و استفاده از نتايج بدست آمده از تحليل اجزاي محدود، فرمولي تقريبي براي طراحي كف مشبك پيشنهاد شده است. اين رابطه­ پيشنهادي، به طراحان ساختمان­هاي صنعتي و دستگاه­هاي حساس به ارتعاش كمك مي­كند كه طرحي اوليه و مناسب را براي طراحي كف مشبك با توجه به پارامترهاي موثر بر ارتعاش كف بدست آورند.

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