Search for: vertical-excitation
A study of endurance time method in the analysis of elastic moment frames under three-directional seismic loading, Article Asian Journal of Civil Engineering ; Volume 11, Issue 5 , 2010 , Pages 543-562 ; 15630854 (ISSN) ; Estekanchi, H ; Sharif University of Technology
Endurance Time (ET) method is a time history based analysis procedure that applies special intensifying acceleration functions for estimating the seismic performance of structures at different excitation levels in each single analysis. One of the extensions of the ET method is in the seismic assessment of buildings considering multi-component excitation. In this paper, a procedure for three-directional seismic analysis of buildings is proposed and application of this method to several steel moment frames is investigated. Several Steel Moment Frames were designed according to INBC Code. These Frames were analyzed under ET acceleration functions in horizontal and vertical directions...
The Effect of Vertical Excitation on the Response of Soil-Structure Systems Allowed to Uplift, M.Sc. Thesis Sharif University of Technology ; Ghannad, Mohammad Ali
The simultaneous effect of uplift phenomenon and vertical vibration of soil-structure system is investigated in this study. The super-structure is modeled as an equivalent single-degree of freedom with bilinear behavior mounted on a rigid foundation resting on distributed tensionless Winkler springs and dampers. The effect of vertical excitation on the response of soil-structure systems allowed to uplift is investigated parametrically through time history analysis for a wide range of systems subjected to sine pulse and a group of ground motions recorded on the soil type of C. The results consist of maximum displacement of the uplifting system and ductility demand of the super-structure as a...
Buckling behavior of the anchored steel tanks under horizontal and vertical ground motions using static pushover and incremental dynamic analyses, Article Thin-Walled Structures ; Volume 112 , 2017 , Pages 173-183 ; 02638231 (ISSN) ; Rahimzadeh Rofooei, F ; Khajeh Ahmad Attari, N ; Sharif University of Technology
Elsevier Ltd 2017
This paper investigates the static and dynamic buckling of an anchored cylindrical steel tank subjected to horizontal and vertical ground acceleration. The buckling capacity of the tank is estimated using static pushover (SPO) and incremental dynamic analyses (IDA). Appropriate load patterns due to the horizontal and vertical components of ground excitations are utilized for SPO analyses. The buckling capacity curves and critical buckling loads computed using SPO analyses are compared to those obtained from IDA. A proper vertical to horizontal acceleration ratio (av/ah) for SPO analysis is proposed that leads to good agreement between SPO and IDA results. © 2017
Adsorption of pollutant cations from their aqueous solutions on graphitic carbon nitride explored by density functional theory, Article Journal of Molecular Liquids ; Volume 260 , 15 June , 2018 , Pages 423-435 ; 01677322 (ISSN) ; Shamkhali, A. N ; Tafazzoli, M ; Parsafar, G ; Sharif University of Technology
Elsevier B.V 2018
In this study, adsorption of important pollutant cations on the surface of graphitic carbon nitride (g-C3N4) was investigated by density functional theory. The calculations indicated that N6 cavity surrounded by triazine units is the most probable adsorption site on this surface. The structural optimizations also predicted a planar surface for Cr3+, and Ni2+/g-C3N4 systems while the structure of the surface for other systems indicated a considerable distortion with strong dependency on the cation size. Also, g-C3N4 surface exhibited the high adsorption energies for Cr3+, As3+, and Sb3+ ions in the gas phase. However, formation energies of the metal-aquo complexes of these cations indicated...
Dynamic analysis of rectangular liquid containers in three-dimensional space, Article Canadian Journal of Civil Engineering ; Volume 33, Issue 5 , 2006 , Pages 501-507 ; 03151468 (ISSN) ; Mirzabozorg, H ; Ghaemian, M ; Sharif University of Technology
A new method for seismic analysis of containers in three-dimensional space is introduced in which the effects of both impulsive and convective components and their corresponding damping are accounted for in time domain. A case study is performed to investigate the behaviour of a concrete rectangular container under the effects of horizontal and vertical ground motions using the scaled earthquake components of the 1940 El-Centro earthquake record. Two-dimensional behaviour of the tank is assumed. The results of the study are compared with those obtained using the current practice and those determined from finite element (FE) analysis based on a lumped mass model. The results of the FE...
Seismic Response and Buckling behavior of Aboveground Cylindrical Steel Tanks, Ph.D. Dissertation Sharif University of Technology ; Rahimzadeh Rofooei, Fayaz ; Khaje Ahmad Attari, Nader
In this study, the seismic response of aboveground, anchored cylindrical steel tanks subjected to horizontal and vertical ground acceleration is investigated. The buckling capacity of the steel tanks is estimated using static pushover (SPO) and incremental dynamic analyses (IDA). Finite element models of a broad tank and a tall tank with height to diameter ratios (H/D) of 0.40, 0.80 and with a liquid level of 90% of the height of the cylinder were used in this study. Appropriate load patterns due to the horizontal and vertical components of ground excitations are utilized for SPO analyses. The influence of the vertical component of ground acceleration on buckling capacity curve of the tank...
A modal approach to second-order analysis of sloshing using boundary element method, Article Ocean Engineering ; Volume 38, Issue 1 , Volume 38, Issue 1 , 2011 , Pages 11-21 ; 00298018 (ISSN) ; Ghasemi, M ; Haddadpour, H ; Sharif University of Technology
This paper aims at developing a modal approach for the non-linear analysis of sloshing in an arbitrary-shape tank under both horizontal and vertical excitations. For this purpose, the perturbation technique is employed and the potential flow is adopted as the liquid sloshing model. The first- and second-order kinematic and dynamic boundary conditions of the liquid-free surface are used along with a boundary element model which is formulated in terms of the velocity potential of the liquid-free surface. The boundary element model is used to determine the natural mode shapes of sloshing and their corresponding frequencies. Using the modal analysis technique, a non-linear model is presented for...