Plastic hinge properties play a crucial role in predicting the nonlinear response of structural elements. The plastic hinge region of reinforced concrete normal beams has been previously studied experimentally and analytically. The main objective of this research is to evaluate the behavior of the plastic hinge region of reinforced concrete deep beams and its comparison with normal beams through finite element simulation. To do so, ten beams contain six deep beams, and four normal beams, under concentrated and uniformly distributed loading, are investigated. Lengths in the plastic hinge region involving curvature localization, rebar yielding, and concrete crushing zones are studied. The results indicate that the curvature localization zone is not suitable for the prediction of plastic hinge length in reinforced concrete deep beams. Based on the results it can be stated that in simply supported normal beams the concrete crushing zone is focused on the middle span, but in simply supported deep beams by creating a compression strut between loading place and support, the concrete crushing zone spreads along the compression trajectory. The rebar yielding zone of simply supported beams increases as the loading type is changed from the concentrated load at the middle to the uniformly distributed load.

Progressive collapse studies generally assess the performance of the structure under gravity and blast loads, while earthquakes may also lead to the progressive collapse of a damaged structure. In this study, the progressive collapse response of concentrically braced dual systems with steel moment-resisting frames was assessed under seismic loads through pushover analysis using triangular and uniform lateral load patterns. Two different bracing types (X and inverted V braces) were considered, and their performances were compared under different lateral load patterns using the nonlinear static alternate path method recommended in the Unified Facilities Criteria (UFC) guideline. Eventually, the seismic progressive collapse resistance of models was compared to their progressive collapse response under gravity loads. These studies showed that models under the seismic progressive collapse loads satisfied UFC acceptance criteria and limited rehabilitation objective. The structures had better performance under seismic progressive collapse than models under gravity loads because of more resistance, ductility, suitable load redistribution, and more structural elements that participated in load redistribution. Furthermore, despite studies on progressive collapse under gravity loads, the dual system with X braces showed better progressive collapse performance (more resistance, residual reserve strength ratio and ductility) under seismic loads than the model with inverted V braces.

در این مقاله ابتدا به اثبات برخی از قضایای نقطه ثابت دوتایی در فضاهای متریک مخروطی مرتب جزئی بر نگاشت هایی که دارای خاصیت یکنوای آمیخته هستند پرداخته و سپس یکتایی این نقاط ثابت دوتایی را تحت شرایطی اثبات می نماییم. در قضایای مذکور فضاهای متریک مخروطی مرتب، لزوماً نرمال نیستند؛ و در پایان به بیان کاربردی از نتایج اصلی در معادله انتگرال می پردازیم. با وجود آنکه دوو در مقاله [W. S. Du, A note on cone metric fixed point theory and its equivalence, nonlinear analysis, 72(2010) 2259-2261. ] نشان داد که نتایج نقطه ثابت در فضاهای متریک مخروطی دارای خاصیت انقباض خطی در فضاهای متریک برقرار است، اما دوو در مقاله [W. S. Du, New cone fixed point theorems for nonlinear multivalued maps with their applications, Applied Mathematic Letters, 24(2011)172-178] و همچنین جانکوویچ و همکاران در مقاله [S. Jankovic, Z. Kadelburg, S. Radenovic, On cone metric spaces: A survey, nonlinear analysis, 74(2011) 2591-2601. ] ثابت کردند که هرگاه فضاهای متریک مخروطی غیرنرمال باشند، قضایای فضای متریک ممکن است برقرار نباشند. نتایج این مقاله به این دسته از فضاها اختصاص دارد.