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Due to earthquake science advances, the prediction of probable earthquake intensity in different regions is approximately possible. But it is not possible to predict the time of earthquake occurrence, so there should be considered some other measures to have the lowest losses during this natural event. This research aims to predict the losses and damages caused by the earthquake and to utilize statistics and population structure using SELENA software. HAZARD US method is used in this study. In this method, the response curve achieved based on soil type and IBC-2006 standard and damping effect of structures listed on the FEMA 440 approach is applied. The results show that because of old structures and population density, the fabric of the old city including regions 1 to 4 and 10 to 12are more vulnerable.

Risk analysis pipelines in the quake as one of the most vital arteries in the current circumstances in the world is of special importance. in our everyday activities, used to underground structures such as pipes, tunnels, wells and so on for services such as transporting water, transportation, irrigation, drainage, sewage disposal, transporting oil and gas, carrying acid waste, industrial, household and so on. With regard to the huge investments structures, especially buried underground pipes, we need to study these constructs in response to the earthquake, is clearly felt. Pipelines used for transporting gas and other fluids, are widely distributed in all areas. These lines due to passing through the densely populated areas are always buried in the earth. Seismic behavior of these pipes as a result of the interaction between the soil and the pipe is different from the above-ground structures. The manner of modelling of the effects of soil liquefaction on the pipes in this thesis is that two shear springs and a normal spring is defined between soil and the pipe that in liquefaction mode minimize the friction shear strength.

The dynamic analysis of concrete arch dam by employing wavenumber approach has been investigating. In previous studies, the analysis was limited for concrete gravity dam. It is well-known that the difficult approach for solving this problem relies heavily on employing a three-dimensional semi-infinite fluid element. The hyper-element is formulated in frequency domain and its application in this field has led to many especial purpose programs which were demanding from programming point of view. In this paper, the method is initially described. Subsequently, the response of Morrow Point dam-reservoir system is obtained by wavenumber approach, and the results are compared against the exact response. Based on this investigation, it is concluded that this approach can be anticipated as a great substitute for the rigorous type of analysis.

In our country, concrete is commonly used for the construction of bridges deck. But the Heavy weight of concrete decks and the impossibility of making them as long-span bridges deck has caused the engineers to think a new material that besides lightness and ease of implementation can provide a good resistance against applied loads including both dead loads and dynamic loads caused by the passage of motor vehicles and also it causes to accelerate the projects implementation in compared with the specimens has made by concrete materials. Space structures due to the lightness, ease and speed of implementation, are considered a suitable replacement for deck bridges. Since the variations of members diameter and thickness can affect the behavior of structures and deflection due to dead and moving loads, so choosing an appropriate diameter and thickness for each member, in addition to impact on structures behavior and deflection of dead and moving loads, this factor has a major impact on buckling of members. Therefore, in this study by changing the member diameter, are investigate the behavior of bridges deck built with spatial structures.

Vulnerable buildings and their rehabilitation are important problems for earthquake regions. In recent decades the goal of building rehabilitation and strengthening has gained different rehabilitation systems. However, most of these strengthening techniques disturb the occupants, who must vacate the building during renovation. Several retrofitting techniques such as addition masonry infill wall, application of buckling restrained braces and local modification of components has been studied in order to improve the overall seismic performance of such buildings. In response to many of the practical issues and economic considerations, engineers use often convergent unbuckling steel bracing frames as the lateral load resisting system during an earthquake.This kind of bracings increases the hardness and strength of concrete structures.The aim of the present study is the evaluation and comparison of seismic performance and retrofitting of an existing 7-storeys concrete structure with buckling restrained bracings and shear walls by nonlinear static procedure (NSP) and accordance with cod-361. The results show that the buckling restrained bracing, decreased drift to acceptable levels and Structure behaves on the life safety of performance level.

Common methods analysis and design of structures are based according to elastic analysis and and reduction of earthquake forces. This reduction design load in the codes is done by the behavior factors. Applying the non-linear static analysis and make ideals pushover curves obtained from its, including conventional in determining behavior factor. The purpose of this study is evaluating the accuracy of nonlinear static analysis in determining behavior factor reinforced concrete moment-resisiting framesby performing nonlinear incremental dynamic analysis that is a more accurate analysisby considering the damping, dynamic nature of the load and higher modes effects. The response modification factors for reinforced concrete moment-resisiting framesobtained in this study by performing nonlinear incremental dynamic analysis are difference about %13 those obtained by pushover analyses analysis. The results of nonlinear incremental dynamic analysis are generally more than those obtained from pushover analysis.

Having very simplicity, nonlinear static procedures (NSPs) are the most popular tools for estimation of structural capacity. These approaches construct a graphic display of the overall structural response via a pushover curve. The overall response of the system provides a direct simulation of the building as single degree of freedom (SDOF) system that simplifies the design and evaluation of the structure. In this research, the first step in any nonlinear static analysis or in other words perform a pushover analysis has been studied. Applied lateral load to the structural model not only affects the overall responses of the structure through structural capacity curve, but also directly affects the local responses of the structure. In order to evaluate these lateral loads, steel buckling restrained braced frame structures are examined by advanced modal pushovers. Next, the results of these pushover analyses will be compared with nonlinear time history analysis as the most accurate method. Finally, the most efficient method in this particular structure is introduced. The analysis conducted in these structures shows that the lateral load pattern based on story shears offers a good prediction of the maximum response of the concentrically buckling restrained braced frame buildings.

Nowadays, various factors complicate the decision making process and the need to make decisions that consider all the factors in question, they are more than ever before. The internal and external researchers, have shown interest in the multi-criteria decision making. In our study, the method includes a multi-criteria decision making method such as Analytical Hierarchy Process, Simple additive weighting and TOPSIS )Technique for order-prefrence by similarity to ideal solution( to solve the selection problem of building efficient systems we have used. Systems that have been evaluated in this issue include: Lightweight Steel Frames, Insulating concrete formwork, 3D-PANEL and Prefabricated reinforced concrete systems. Required data using the questionnaire sample (n = 150) were examined. Questionnaires among the mass of experts, academic institutions and conferences were distributed. According to the research results, using different methods of decision making, the results will yield fairly similar, so that all three methods, Prefabricated reinforced concrete systems in the first place, and the Lightweight Steel Frames system was in the Second place. The Prefabricated reinforced concrete systems, in terms of administrative and economic criterias, in the first place, and the system Lightweight Steel Frames, ranked first in terms of environmental criteria accounted for.

This paper was present a seismic hazard analysis and uniform hazard spectra for different regions of Kerman city. A collected catalogue containing both historical and instrumental events and covering the period from 8th century AD until now within the area of 200 Km in radius were used and Seismic sources are modeled. Kijko method has been applied for estimating the seismic parameters considering lack of suitable seismic data, inaccuracy of the available information and uncertainty of magnitude in different periods. To determine the peak ground acceleration the calculations were performed by using the logic tree method. Two weighted attenuation relations were used; including Ghodrati et al, 0.6 and Zare et al, 0.4. Analysis was conducted for 13×8 grid points over Kerman region and adjacent areas with SEISRISK III software and in order to determine the seismic spectra Ghodrati et al, spectral attenuation relationships was used.

Public private partnership has been used extensively in both developing and developed countries in delivering various types of projects, ranging from transportation projects, health care facility and power plants. The high speed rail projects which implemented by public private partnership in recent years has faced with difficulties. This paper aims to develop an identification and assessment method for critical risks of public private partnershiphigh speed rail project in Iran. In this research at first, risks of public private partnershiphigh speed rail projects are identified by integration of extensive literature review and Public private partnership high speed rail project experience in Iran and other countries. In the next step, the identified risks are assessed by questionnaire survey and multivariate statistical analysis. Analytical investigations show that the number of critical risks in high speed rail projects and their mean importance is higher than that of general public private partnership projects. In this study in addition of confirming pre identified risk groups consisting political and financial groups, two major groups of initialisation and contractual risks specific to high speed rail projects are identified and two groups specific to developing countries named circumstances and private risks are proposed. Because of insufficient studies and lack of experience in developing countries about transportation mega projects via Public private partnership this study can be a helpful reference for public private partnership implementation of high speed rail mega projects in developing countries.