Basics of dynamic PUSH-OVER analysis and static PUSH-OVER are same. But in the dynamic case the wave or seismic loads are exerted to structure dynamically. With increasing intensity of dynamic loading in every step, structure would then be analyzed. Results of these two analyses are “PUSH-OVER graphs” that show behavior of structure. Two platforms were selected for investigation. At first static PUSH-OVER analysis and then dynamic PUSH-OVER was performed for two platforms. Results of the two analyses were compared to each other. FEM based program “ABAQUS” was used for modeling. In this investigation, following results were found: Jackets behavior in both dynamic and static PUSH-OVER analysis is same for linear range of jacket behavior, but in nonlinear range, results are different. In dynamic PUSH-OVER analysis reserve strength of jacket structures was estimated to be higher than that of static PUSH-OVER analysis. In dynamic PUSH-OVER analysis ductility capacity was increased compared with static PUSH-OVER and structure can bear more partial failure in comparison with static case.

Many existing buildings are irregular in plan or elevation because of asymmetric placement of masonry infills. The stiffness of masonry infill is a considerable value relating to that of the structure. Produced torsion from eccentricity because of infill stiffness leads to extra forces and deformations in structural members and diaphragms. An appropriate alternative to solve this problem especially in existing buildings is using dampers. Dampers can enhance structural performance by reducing seismically induced lateral displacements and by reducing inelastic behavior of beams and columns. In this paper some simple models are used to show structural modeling and a conceptual discussion is presented on the numerical results. An accurate model for masonry infill has been used in structural model. Numerical results show the efficiency and high performance of added dampers to reduce the torsion effects in the structural elements.

Dynamic characteristics of steel structures including flexural frame system with semi-rigid connections are investigated in this study. With this regard, four frames have been modeled including two-span two-story, three span four-story, three-span six-story and four-span eight-story frames. The frames are analyzed and evaluated for variation of the connections stiffness from semi-rigid to rigid and for both cases of PUSH OVER static analysis and nonlinear dynamic analysis under earthquake acceleration. After that, plastic hinge formation in the frame, frame failure, energy dissipation in members and connections, maximum displacement of stories and frame, base shear force, behavior coefficient, coefficient of design load increased strength have been investigated.The results showed that stiffness increase of connections in the frame, increases the base shear force and coefficient of increased strength, and reduces the period, maximum and relative displacement (drift) and coefficient of frame behavior.

RC buildings has been constructed in our country for decades. Many of the existing buildings have been designed and implemented when well-known seismic design bases have not been common, so these buildings are not strong enough. The purpose of this research was to investigate the technical and economic effects of retrofitting methods on the technical and economical effects of two retrofitting methods including buckling restrained braces and retrofitting using a concrete shear wall. The results of this study showed that with the use of retrofitting, the amount of displacement of the target in the models has significantly decreased, and it is observed that the concrete shear wall has more effect on the structure. drift also been reduced by retrofitting, and this amount has been reduced by adding a concrete shear wall in comparision to buckling braces. Also, the evaluations showed that, despite the fact that the reinforced concrete shear wall had a better technical effect on the structural performance, it is observed that the use of a buckling brace is more economical.

Results of seismic damage evaluation of a tall reinforced concrete building are presented. Plastic hinge formation patterns obtained by using DRAIN-2D and IDARC computer programs for dynamic analysis are compared. Damage indices given by IDARC are interpreted and their implications compared with those of drift ratios. Results of static PUSH-OVER analysis are compared with those of inelastic dynamic time history analysis. MoreOVER, the result of collapse mechanism approach is compared with that of static PUSH-OVER analysis. It is shown that simple collapse mechanism approach can predict the failure mode given by static PUSH-OVER analysis for this building. It is concluded that drift limits in codes do not necessarily predict the degree of damage that this type of construction can sustain in severe earthquakes.

Iran, due to its geographical location, has low rainfall and is considered a dry land. As a result, different regions of the country grapple with drought. The presence of water management systems, such as aqueducts and reservoirs, in most parts of the country, along with a variety of methods for conserving water for irrigation, may contribute to this claim. Considering that drought is an inherent phenomenon in Iran's climate, people have invented and used numerous methods to combat it and store water. The aim of this study is to monitor and evaluate drought in Iran. In order to realize this goal, precipitation data from synoptic, rain gauge, and climatology stations were extracted OVER a 51-year period, from 1970 to 2020. The results obtained from examining drought occurrences in five ten-year periods reveal that, with the exception of the third decade (1991 to 2000), drought has prevailed in the majority of Iran's regions compared to other decades. On the other hand, in the recent decades leading to 2020, the intensity of drought occurrences, especially in the Middle Zagros, has intensified, which has consistently been among the regions with the highest rainfall in Iran after the Caspian region. This situation can cause concern in Iran, a country where its agricultural production hub is established along the Zagros mountain range. MoreOVER, the fluctuating behavior of Iran's droughts, with return periods of 2 to 5 years, has complicated the management strategies for these types of hazards. These conditions appear to have created numerous issues in many areas of Iran, particularly in the agricultural sector of the western provinces, due to the lack of conformity with these types of occurrences.

In this paper, the effect of number of stories, link length (e/l ratio), vertical loading level and strain hardening ratio on seismic OVER strength factor W of different moment-resisting eccentrically braced steel frames under three different earthquake ground motions is studied. For this purpose nonlinear static PUSH-OVER analysis is used. Then a new method is presented to evaluate seismic OVER strength factor of steel moment resisting eccentrically braced frames using nonlinear incremental dynamic analysis (IDA). Incremental Dynamic Analysis (IDA) is an emerging analysis method which involves performing nonlinear dynamic analysis of the structural model under a suite of ground motion records, each scaled to several intensity levels designed to force the structure all the way from elasticity to final global dynamic instability, thus producing curves of response parameterized versus intensity level. To demonstrate the proposed methodology three ground motion records are selected and scaled to several levels of intensity and subsequently applied to three different steel frames with dual lateral load resisting systems of Moment Resisting (MR) and Eccentrically Braced Frames (EBF). DRAIN-2DX is used for all static and dynamic analysis.

In microwave oscillators, the quality factor of the resonators decreases with an increasing frequency. There exist some methods for compensating the losses in the resonators. The PUSH-PUSH configuration is able to improve the oscillator phase noise. In this work, a PUSH-PUSH voltage-controlled oscillator utilizing a parallel coupled resonator has been designed for the frequency range of 1200-1400 MHz. The PUSH-PUSH oscillator consists of two similar Collpits oscillators, which are designed for the frequency range of 600-700 MHz. These sub-oscillators are coupled by a phase coupling network and with 180 degrees phase difference. The in-phase combiner combines the even harmonics of each sub-oscillator and cancels the fundamental and odd harmonics. The OVERall oscillation of the PUSH-PUSH oscillator consists of the second and even harmonics of the sub oscillators. By this technique, the phase noise is improved 9 dB compared to the case of the stand-alone oscillation of each sub circuit at the output frequency.