ارزيابي روش هاي رايج پوش آور براي سازه هاي بتن مسلح نامنظم در پلان

تحليل استاتيكي غيرخطي (پوش آور) به دليل سهولت كاربرد و هزينه محاسباتي كمتر به عنوان جايگزيني مناسب براي روش تاريخچه زماني غيرخطي معرفي شده است. محققان روشهاي پوش آور مختلفي را براي سازه هاي دوبعدي ارايه كرده اندكه ارزيابي آنها در سازه هاي واقعي سه-بعدي و نامنظم ضروري به نظر مي رسد. در پژوهش حاضر، كارايي روش هاي رايج پوش آور در پيش بيني پاسخ قاب هاي سه بعدي بتن مسلح با استفاده از المان هاي غيرخطي نيرويي فيبري ارزيابي شده است. قاب هايي با درجات متفاوت نامنظمي پلاني به روش هاي پوش آور با توزيع بار ثابت، پوش آور با توزيع بار مثلثي معكوس، آناليز پوش آور به هنگام شونده نيرويي مودال و آناليز پوش آور به هنگام شونده نيرويي طيفي تحليل شده و پارامترهاي نيرو و جابجايي با نتايج تحليل ديناميكي غيرخطي دو مولفه اي تحت شتابنگاشت هاي حوزه هاي دور و نزديك گسل، مقايسه شدند. نتايج حاصل نشان مي دهد گرچه رويكرد چند روشي مي تواند تصوير بهتري از پاسخ سازه اي قاب هاي سه بعدي بتن مسلح ارايه دهد اما روش هاي به هنگام شونده بطور متوسط از موفقيت بالاتري در پيش بيني رفتار غيرخطي اينگونه سازه ها برخوردارند. Because of its relative simplicity and less computing costs, Pushover analysis, gains a supremacy over nonlinear time history analysis in structural engineering communities. Researchers conducted several 2D pushover methods that their efficiency in real 3D structures should be evaluated. In this research the proficiency of common pushover analysis procedures to predict the response of 3D in-plan Irregular reinforced concrete frames has been evaluated. Several RC frames with different in-plan Irregularities and heights was analysed using conventional pushover analysis with rectangular and triangular loading scheme, modal pushover and forced-based adaptive pushover analysis. Comparing results with bi-directional nonlinear dynamics analysis using ordinary and near-fields seismograms indicate that although the multi-procedure approach can present a better picture of the structural response of 3D RC frames, the more advanced procedures in contrast to other procedures, on the average, have higher achievements on predicting nonlinear behaviour of such structures.

Because of its relative simplicity and less computing costs, Pushover analysis, gains a supremacy over nonlinear time history analysis in structural engineering communities. Researchers conducted several 2D pushover methods that their efficiency in real 3D structures should be evaluated. In this research the proficiency of common pushover analysis procedures to predict the response of 3D in-plan Irregular reinforced concrete frames has been evaluated. Several RC frames with different in-plan Irregularities and heights was analysed using conventional pushover analysis with rectangular and triangular loading scheme, modal pushover and forced-based adaptive pushover analysis. Comparing results with bi-directional nonlinear dynamics analysis using ordinary and near-fields seismograms indicate that although the multi-procedure approach can present a better picture of the structural response of 3D RC frames, the more advanced procedures in contrast to other procedures, on the average, have higher achievements on predicting nonlinear behaviour of such structures