Sharif Digital Repository

One of the most important elements of performance-based seismic engineering elements is precision in determination of seismic displacement demand evaluation. Although seismic demands which are estimated by utilizing non-linear dynamic analysis are most effective, but with regards to inherent complexities of these methods and demands for time-consuming calculations , non-¬linear static methods seems to be an appropriate representative and is recently considered by engineers. In countries with oil resources including Iran, offshore jacket platforms are among outstanding structures being considered. Inasmuch as high design and execution expenses of these structures and also important role of... 

The AISC Seismic Design Provisions include capacity design requirements for steel plate shear walls since 2005. This system consist of thin web plates that infill frame panels with steel beams as horizontal boundary elements (HBEs), and columns as vertical boundary elements (VBEs). The thin unstiffened web plates are expected to buckle in shear at low load levels and develop tension field action, providing ductility and energy dissipation through tension yielding of the web plate. HBEs are designed for stiffness and strength requirements and are expected to anchor the tension field formation in the web plates. VBEs are designed for yielding of web plates and plastic hinge formation at the... 

The aim of this research is to study performance of Rao Score Test control chart in phase II monitoring of generalized linear profiles for drift and multiple changes which can be isotonic or antitonic. Moreover, the performance of the method is compared with two common methods in the generalized linear profile literature: Hotelling T2 and multivariate exponential weighted moving average. Afterward multivariate cumulative sum chart is proposed to be used in monitoring antitonic multiple change in the parameter of Poisson profiles. Finally, a real world example is presented in which Rao Score Test method is applied to real data and the performance of this method is compared with other methods.... 

Nowadays, according to increasing development of construction industry in the world especially in the building area, the need to use technology and innovation for fabrication and maintenance of this industry has increased. And this fact becomes apparent that the use of traditional systems of construction isn’t tailored the countries’ requirements anymore. One of the construction industry’s limitations is the restrictions on architectural designs reys. The columns are among the most important components of structure and have a major role in bearing all gravity and lateral loads and transferring them to the foundation. The failure or destruction of the components in the structure under applied... 

Seismic design codes reduce loads by using response modification factor. Because of the reserved strength in structural elements and capacity of structure to dissipate energy, structures can be designed for lower seismic loads. This factor has modified over time. In this thesis, the effect of the reduction in behavior factor on the response of two kinds of reinforced concrete systems were evaluated. Moment resisting frames and dual systems with different heights and regularity in plan, heve been design according to the behavior factor which is recommended in the 3rd edition of the Iranian codes of practice for seismic resistance design of buildings (Standard No. 2800). Drift and... 

Structures having buckling restrained braces (BRB) as earthquake resisting system, have the qualities of high lateral stiffness and the ability to damp the energy coming from earthquake, at the same time.In addition to new structures, these braces can also be used in rehabilitating old steel or concrete buildings. By using this kind of resisting system, smaller sections are needed in design of buildings and also the cost of repair after earthquake can be highly reduced.The most important advantage of buckling restrained braces is their equal behavior and capacity in both tention and compression, that causes high energy absorption as a result of symmetric and stable cyclic behavior. All these... 

Over the past two decades, the production of ultra-light drones has increased dramatically. These aircraft are used in applications such as filming, surveying, etc. One of the most important goals is to fly them for a long time. From time immemorial, a lot of work has been done to get such birds to fly, but nothing has ever been done on their engines and propellers, and they have always been considered ideal models (in other words, their efficiency is a bit ideal). In this dissertation, the main purpose is to study some of these sets and to obtain the flight time of a particular drone. First, a low-velocity wind tunnel was built to examine these complexes, then we tested these complexes...