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seismic-vulnerability
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A Study on the Factors Resulting in Low Quality Structures And its Impact on the Seismic Performance of Public Structures in Tehran
,
M.Sc. Thesis
Sharif University of Technology
;
Mortaheb, Mohammad Mehdi
(Supervisor)
;
Ghaemian, Mohsen
(Supervisor)
Abstract
Tehran is surrounded by about ten active faults, which have had no major seismic activity during the last 200 years. Considering soil characteristics, the faults may cause fault ruptures, resonance, landslides in some areas. Tehran's MPE is determined to be about 0.4g which is a high seismic hazard. Specific codes have been generated in the last 50 years to ensure structures' stability when a quake occurs, but observations show that the codes are not fully implemented in the construction of public structures in Tehran. In this study, first the structural imperfections observed in the public structures and their effect on the structures' seismic performance were reviewed. The imperfections...
Quick Evaluation Instructions of Earthquake Damage in the Piping Systems Inside the Industrial Complexes
,
M.Sc. Thesis
Sharif University of Technology
;
Ghannad, Mohammad Ali
(Supervisor)
Abstract
This existing research has been conducted to reach quick evaluation instructions to pipe earthquake damages in the piping systems inside the industrial complexes. In the old complexes of such kinds there are cases where field inspections and quality evaluations are urgently required subject to peculiar conditions affecting each piping system inside the units and in certain cases subject to lack of access to the as built-drawings. However, so far any definite instruction hasn’t been available for a quick evaluation of likely damages in piping system: all because of various pipe types, complexity of pipes geometry, different temperatures and pressures in different sections. In this research...
Vulnerability Assessment of Existing RCMRF Structures Subjected to Near Field Earthquakes
, M.Sc. Thesis Sharif University of Technology ; Rahimzadeh Rofooei, Fayyaz (Supervisor)
Abstract
The objective of this study is to evaluate the seismic vulnerability of the existing buildings subjected to the near field earthquakes. The main applications of this research are loss estimation and performance evaluation of the existing buildings. That could provide a better solution and particularly more useful information to the owners, investors, and insurers about the expected performance of buildings under earthquake excitations. A number of 2, 5 and 8 story reinforced concrete buildings, designed according to the old Iranian seismic provisions of ISIRI-519 and ACI 318-83 codes for the ordinary moment resisting frames, are considered. By the use of a number of near field earthquake...
Seismic Vulnerability Assessment of Masonry Walls by Signal Processing
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
In this study, damage detection of brick masonry walls using a unique signal processing technique has been addressed. Firstly, the pushover analysis and the calibration of the model is performed. Then, the dynamic analysis of the wall under earthquake excitation in three cases with different aspect ratios is conducted. Finally the dynamic properties of the system, namely natural frequency and modal damping ratio, are identified using continuous wavelet transform. The advantage of wavelet transform is its fine time-frequency resolution. The Morlet mother wavelet is used since it can provide the best time-frequency resolution based on Heisenberg uncertainty principle. Afterwards, the...
A Framework to Select the Appropriate Combination of Retrofit and Insurance in Order to Reduce Earthquake Losses
, M.Sc. Thesis Sharif University of Technology ; Haj Kazem Kashani, Hamed (Supervisor)
Abstract
The aim of this research is presentation of A framework to select the appropriate combination of retrofit and insurance in order to reduce earthquake losses. The vulnerability of buildings to earthquakes can lead to significant damage to owners and residents of these buildings. It is imperative that appropriate measures be taken to reduce these adverse effects before the risk occurs. Some of these measures, such as seismic retrofit of buildings, can reduce the vulnerability of buildings and, consequently, financial and human losses. Some other measures like insurance, in the event of an earthquake, can reduce the financial losses incurred by owners and residents of vulnerable buildings....
Development of Fragility Curves for a Number of Existing Buildings in Qazvin
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
The objective of this study is to assess seismic vulnerability and more specifically to develop analytical fragility curves for a number of existing buildings in Qazvin. Fragility curves represent exceedance probability of the structural response from a specific limit state at a given seismic intensity level. In this study, Maximum Interstory Drift Ratio and Spectral Acceleration at fundamental period of the structure with 5% viscous damping are considered as Damage Index and Intensity Measure, respectively. Limit states are also applied as it is suggested in FEMA 356. In order to obtain comprehensive and extensible results as far as possible, the type of buildings under study must be...
Analysis of Seismic Vulnerability Reduction Policies of Residential Buildings Using a Multi-agent Evolutionary Game Model Based on Prospect Theory
, M.Sc. Thesis Sharif University of Technology ; Kashani, Hamed (Supervisor)
Abstract
Due to the vulnerability of urban fabric and residential buildings to earthquakes and considering its destructive social and economic effects on society, the need to adopt appropriate policies to prevent and reduce vulnerability, has been increasingly considered by policy makers. Despite the laws, regulations, incentives and penalties that policymakers have envisioned to prevent unprincipled and unsafe construction, evidence shows that a significant number of new buildings being built in the country are not earthquake resistant and there are many violations in design, implementation and supervision that is done by the stakeholders. To solve this problem, research has been done on the...
Risk based seismic assessment of structures
, Article Advances in Structural Engineering ; Volume 16, Issue 2 , 2013 , Pages 307-314 ; 13694332 (ISSN) ; Tonekaboni, M ; Sharif University of Technology
2013
Abstract
In this paper a new approach to risk based seismic assessment of structures is proposed based on acceptable risk levels. In this approach, the probabilistic seismic vulnerability, predicted lifetime of structure, importance and knowledge factors are considered in the evaluation process. Park & Ang damage index is used to quantify damage states of structure. By performing several incremental dynamic analyses, all damage states of structure from minor to heavy and collapse are considered under all possible ground motions. The structural risk level and the necessity of seismic retrofit measures are specified by seismic risk index of structure. This probabilistic performance based method is...
Quantitative Evaluation of Seismic Vulnerability of Reinforced Concrete Bridges Pier's Using the Theory of Distributed Plasticity, Plastic Hinges and C/D Methods and Compare their
, M.Sc. Thesis Sharif University of Technology ; Vafaei, Abolhassan (Supervisor)
Abstract
Performance based design was first introduced in order to evaluate seismic vulnerability of structures in retrofitting topic and was rapidly implemented in new design codes. The main cause conducting widely developing of performance based design methods, has been accurate estimation of seismic demand parameters. Since seismic structural members displacement during earthquake has a direct effect on the amount of sustained damages, displacement index has always been a key concept in performance based design. The main goal followed by this research is comparing the results obtained from the standard pushover method (with two theorems of distributed plasticity and plastic hinges) and the...
Machine Learning-Based Rapid Visual Screening of Buildings for Potential Seismic Damage Using BuildingImages
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
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,...
Risk assessment of confined unreinforced masonry buildings based on FEMA P-58 methodology: a case study—school buildings in Tehran
, Article Bulletin of Earthquake Engineering ; 30 October , 2020 ; Bakhshi, A ; Ghannad, M. A ; Panahi, M ; Sharif University of Technology
Springer Science and Business Media B.V
2020
Abstract
Seismic performance of a representative single-story confined unreinforced masonry school building in Tehran, Iran is evaluated by means of incremental dynamic analyses according to FEMA P-58 framework. For this purpose, fragility curves are derived for each of the constituent walls of the building. The in-plane behavior of the walls is considered only. Both flexible and rigid diaphragm conditions are investigated. For comparison purposes, the corresponding unconfined building exactly duplicating the considered confined unreinforced masonry building is also studied. In order to analyze the effects of near-source seismic actions on the performance of masonry buildings, two separate far-field...
Efficient seismic risk assessment of irregular steel-framed buildings through endurance time analysis of consistent fish-bone model
, Article Structural Design of Tall and Special Buildings ; 2021 ; 15417794 (ISSN) ; Hosseini, M ; E. Estekanchi, H ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
The seismic risk framework of building structures has been presented to reduce earthquake-induced adverse consequences. In this context, probabilistic analysis of engineering demand parameters (EDPs) is always associated with many uncertainties and high computational demand for use in practical applications. This study has been presented to efficiently estimate the distribution of EDPs in probabilistic seismic risk assessment of irregular steel moment-resisting frames (SMRFs). For this purpose, the incorporation of the consistent fish-bone (CFB) model and the endurance time (ET) analysis method has been used. The proposed method (i.e., CFB-ET) has a substantial impact on reducing the...
Efficient seismic risk assessment of irregular steel-framed buildings through endurance time analysis of consistent fish-bone model
, Article Structural Design of Tall and Special Buildings ; 2021 ; 15417794 (ISSN) ; Hosseini, M ; E. Estekanchi, H ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
The seismic risk framework of building structures has been presented to reduce earthquake-induced adverse consequences. In this context, probabilistic analysis of engineering demand parameters (EDPs) is always associated with many uncertainties and high computational demand for use in practical applications. This study has been presented to efficiently estimate the distribution of EDPs in probabilistic seismic risk assessment of irregular steel moment-resisting frames (SMRFs). For this purpose, the incorporation of the consistent fish-bone (CFB) model and the endurance time (ET) analysis method has been used. The proposed method (i.e., CFB-ET) has a substantial impact on reducing the...
BIM and machine learning in seismic damage prediction for non-structural exterior infill walls
, Article Automation in Construction ; Volume 139 , 2022 ; 09265805 (ISSN) ; TohidiFar, A ; Alvanchi, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Despite the seismic vulnerability of non-structural Exterior Infill Walls (EIWs), their resilient design has received minimal attention. This study addresses the issue by proposing a novel framework for predicting possible damage states of EIWs. The framework benefits from an automated combination of Building Information Modeling as a visualized 3D database of the building's components and the Machine Learning classification as the prediction engine. The framework's applicability is studied in a Proof of Concept example of the exterior walls of the buildings damaged in the 2017 earthquake in Kermanshah, Iran. The Extremely Randomized Trees classifier produced the best results for predicting...
Efficient seismic risk assessment of irregular steel-framed buildings through endurance time analysis of consistent fish-bone model
, Article Structural Design of Tall and Special Buildings ; Volume 31, Issue 2 , 2022 ; 15417794 (ISSN) ; Hosseini, M ; E. Estekanchi, H ; Sharif University of Technology
John Wiley and Sons Ltd
2022
Abstract
The seismic risk framework of building structures has been presented to reduce earthquake-induced adverse consequences. In this context, probabilistic analysis of engineering demand parameters (EDPs) is always associated with many uncertainties and high computational demand for use in practical applications. This study has been presented to efficiently estimate the distribution of EDPs in probabilistic seismic risk assessment of irregular steel moment-resisting frames (SMRFs). For this purpose, the incorporation of the consistent fish-bone (CFB) model and the endurance time (ET) analysis method has been used. The proposed method (i.e., CFB-ET) has a substantial impact on reducing the...
On the modal incremental dynamic analysis of reinforced concrete structures, using a trilinear idealization model
, Article Engineering Structures ; Volume 33, Issue 4 , 2011 , Pages 1117-1122 ; 01410296 (ISSN) ; Mofid, M ; Sharif University of Technology
Abstract
In order to estimate the seismic demands at the performance level, the inelastic behavior of concrete structures should be considered. Incremental dynamic analysis (IDA) based on a nonlinear response time history analysis (NL-RHA) is considered to be the most accurate method in seismic demand calculations. However, modal incremental dynamic analysis (MIDA), based on the equivalent single-degree-of-freedom (SDF) oscillator, is also often used in studying structural engineering performances. As the MIDA method has usually not been applied to reinforced concrete (RC) structures, in this study an attempt is made to investigate the performances of RC frames and to compare the results obtained...