درخت حوزه‌های تخصصی

Applied studies addressing semi-rigid connections have been limited. Scant information exists in regulations except little brief information. Therefore, this research analyzes the behavior of three-dimensional steel frames and semi-rigid connections based on beam-column method and non-linear dynamic analysis. Stability functions and geometric stiffness matrix were used to study the non-linear geometric behavior of members. Then the dynamic behavior of rotational springs was simulated by stiffening, and the non-linear load-displacement responses and the final results were compared to prior studies that have taken place. It was finally concluded that the method used to analyze the semi-rigid connections was efficient, and if one element per member is used and a precise monitoring is delivered, end sections and nonlinear steel frames behavior with semi-rigid connections can be predicted.

Following the creation of economic, social and environmental issues in metropolises, strategies aimed to build new cities to decentralize, attract the overflow of crowed population and reduce its activity, in order to enhance the quality of life and to organize the population and activity in urban areas. In the present study, the role of spatial planning for new towns in the metropolitan suburbs of Mashhad or in other words, the role of these new towns on the space balance, creating the employment and self-sufficiency and to absorb some part of Mashhad’s population has been studied. In this regard, in addition to the library studies and comparisons of existing status with the predicted targets for studying new cities, two series of questions regarding the condition of every new town, as well as analysis network process (ANP) were used to assess their success and to rank them. Results showed that the infrastructure’s indicator plays the greatest role in the success or failure of these cities in achieving their goals, so if the government does not provide the platform and infrastructure, new towns policy does not help resolve the crisis of metropolitans. After infrastructure, employment, attraction of people and accessibility have almost equally important and are in secondary importance. Eventually, our results revealed that Gulbahar has been more successful than Binalud, According to the results of the present study, the coordinated and proper management at national and regional levels, especially in the Mashhad conurbation, creation of employment opportunities, improving the identify and the quality of new towns and provide appropriate services is necessary and essential to citizens.