Sharif Digital Repository

The purpose of this research is to investigate the seismic behavior of plane moment resisting frame consisting of steel-concrete columns and steel I beams utilizing fragility curves. Due to the great influence of the column type in seismic performance of structure. To reach an optimal system, different types of steel-concrete composite columns has been used in the models and the fragility curve of each one is compared. Steel-Concrete composite columns can be divided into three types: (1) concrete filled steel tube (CFT), (2) steel reinforced concrete (SRC) and (3) new combinations of (1) and (2). Due to the abundance of the use of concrete filled steel tube (CFT) and steel reinforced... 

The main purpose of this research is to evaluate the probabilistic benefit of the implementation of second isolation layer in isolated structures to both the structure and the constructor. The innovation of this research is in the utilization of a seemingly useless part of the structure, which is the ridge, for mitigating the structure’s displacement. For this purpose, a five-story residential structure and its ridge have been isolated and modeled as an MDOF system with two degree of freedom in MATLAB software and the benefits due to the reduction in displacement and acceleration has been calculated. The results indicate 40 percent reduction in the main structure’s displacement and a benefit... 

The main goal of this study is to calculate the probability of exceedance from each level of failure zone. Seismic base isolation systems are one of the effective method to reduce seismic response of structures. This system helps to improve structural behavior by reducing acceleration and relative displacement of story. On the other hand, the main problem is to increase the base displacement of building. To solve this, these systems are used with passive or semi-active control systems. This type of system has benefits of both passive ad semi-active control simultaneously. Base isolation is less effective in tall structures due to the flexural and shear behavior. In this study Haselton... 

Although electronic banking service has been introduced in Iran for more than a decade، today half of the people who go to the physical bank branches are the ones can do their affairs via e-banking. The banks’ managers attribute the main reason for these unnecessary travels to insufficient trust towards e-banking systems. One of the important tools in this regard is mobile banking which is prevailing around the world، however it has not prevailed enough in Iran. This research has tried to investigate the cognitive and non-cognitive dimensions of trust to mobile banking. The data for this research has been collected from users of mobile bank service who have filled the online research... 

Preservation of historical monuments is a very important issue for future generations. The importance of this issue is doubled when we know that most of these buildings are traditionally built and do not have a single structure to withstand seismic loads. One of such buildings in our country is Bam Citadel, which was completely destroyed as the oldest brick building in the world during the 2003 Bam earthquake.In this project, we will try to find a model that can determine the structural behavior of the historical dome of Soltanieh for engineers in a case study. This building is a brick dome with a height of 48.5 meters and a diameter of 24.4 meters from the seventh century , which is unique... 

The Deep Fading Effect is a destructive factor in communication systems, one of the solutions to eliminate it is the use of Diversity, and there are two types of indicators of Diversity, Spatial Diversity and Polarization Diversity. Spatial Diversity is a common method to reduce the Fading Effect while increasing the cost and increasing the volume of the communication station, which to optimize the cost and reduce the volume of the communication station, the Polarization Diversity Structure is added to the telecommunication system. To apply Spatial Diversity, several Antennas with different Polarizations are used, which The most common method in mobile telecommunication station systems is... 

Reinforced concrete buildings with open ground storey are vulnerable to accumulate of large lateral displacement at the ground story. This is due to drastic reduction in the relative stiffness of the ground story compared to the upper stories, a phenomenon known as soft storey effect. Furthermore inevitable Existence of Opening in masonry infill and increasing it’s area reduces both the lateral strength and stiffness of the fully infilled RC frames so when percentage of the central opening is very high, the behaviour of the infilled frame approaches the bare frame. It is a perception about open ground storey buildings that openings in the upper stories infilled frame offset the soft storey... 

Rapid visual screening is a way to assess unsafe structures and reduce urban earthquake vulnerability. Although this method is faster than detailed analytical methods(e.g. Incremental dynamic analysis), it still requires a lot of time and financial resources to execute. Due to the widespread use of computer vision in engineering, this study has used this technology to perform rapid visual screening, improve its overall process and provide a standard method for automatic assessment of structures. In the process of rapid visual screening, the screener identifies features from the exterior view of the building, which are finally recorded in a scoring system. According to the score obtained,... 

The main purpose of this study is stochastic analysis of base-isolated structures considering soil-structure interaction. Due to stochastic nature of earthquake and existence of uncertainties in non-linear behavior of and properties of soil, it is better to calculate the responses of the structure via random vibrations approach. In this approach first of all, the differential equations of structure are obtained in deterministic vibration mode and then by the available theories, differential equations of covariance of the responses are obtained. Solving these equations leads to the finding of the standard deviations of the responses of the structure in each moment. In backward differential... 

With confidence in the recorded observations, the RLS method no longer estimates the recorded measurements by sensors, i.e. the displacement and speed of the floors, and only estimates the parameters. In contrast, in the EKF method, in addition to estimating the structure's parameters, a more precise estimation of the observations recorded by the sensors has been done by accepting the noise in the recorded observations. These methods, which are based on the Bayesian updating, investigate the two primary sources of uncertainty in a problem: a) measurement noise or observation noise, and b) process noise, which includes modeling errors. In these methodologies, the unknown system parameters,... 

In this research, using sensitivity equations and output-only modal analysis (OMA) methods, a finite element numerical model was updated, and in the updated model, damage identification was performed. The present study, utilizing a sensitivity-based updating method and a validated formulation from the technical literature, conducted the updating process under several different approaches and ultimately verified the fundamental assumptions in the OMA field to demonstrate the validity of the results. The combination of these elements, along with the use of an explicit formulation, establishes a framework for updating finite element models within the OMA field, which is introduced as the... 

The main objective of this thesis is investigation of cold formed steel sections capability for design and performance of beams, plate Girders and special moment resisting frames. Cold framed steel sections have special properties which are different from hot rolled sections and so their capability and efficiency for application in design and performance of beams, plate Girders and CFS-SBMFs must be investigated and studied particularly. In this thesis, the cold work effect on strength and ductility of virgin steel plates, the validity of Karren (AISI) equation and also ECCS (Euro code3) formula for thick plate sections and the failure modes of CFS Angle sections are investigated by...