In order to increase the accuracy of evaluating seismic response of structures, it is critical to conduct dynamic analyses based upon precise nonlinear models being as consistent as possible with the real conditions of corresponding structures. The concentrated plasticity model including one elastic element and two nonlinear spring elements at both ends has been considered within the research c...

‎in this paper‎, ‎we present a new modification of chebyshev-halley‎ ‎method‎, ‎free from second derivatives‎, ‎to solve nonlinear equations‎. ‎the convergence analysis shows that our modification is third-order‎ ‎convergent‎. ‎every iteration of this method requires one function and‎ ‎two first derivative evaluations‎. ‎so‎, ‎its efficiency index is‎ ‎$3^{1/3}=1.442$ that is better than that o...

We study the construction of nonlinear impulse responses in linear structural dynamic models that include nonlinearly transformed regressors. derive closed-form solution for population to a given shock and propose control function approach estimating these without taking stand on how remainder model is identified. Our plug-in estimator dispenses with need simulations and, unlike conventional lo...

Due to their dual behavior under tension and compression, structures with tension-only members show non-linear behavior. To analize such structures, it is necessary to use a nonlinear analysis scheme. Nonlinear analysis methods generally use gradual loading techniques with/without modification of stiffness matrix of the structure. These methods, in addition to being time consuming algorithms, a...

in this paper, pile behavior embedded in layered soil deposits subjected to seismic loadings is analyzed using a nonlinear fiber element for simulation of soil – pile interactions. in the created model, both pile and surrounding soil are modeled using fiber elements in a practical beam on nonlinear winkler foundation (bnwf) concept. herein, the features of drain–3dx finite element software are ...

The design of earthquake-resistant buildings starts with defining the maximum lateral earthquake forces or their resultant. The amount of these forces depends on various factors, including coefficient of system behavior which depends on overstrength and its ductility. In this study, a method is presented for designing an earthquake-resistant system in which the distribution of lateral forces is...

in this paper we have discussed the main features of a finite clement program which we have developed for nonlinear dynamic analysis of plates and shells with material and geometric nonlinear behaviour. for this purpose, initially, the finite element model which we have used is briefly described. afterwards, the nonlinear viscoplastic material model in one-dimensional and multi-dimensional medi...

The nonlinear system becomes an area with numerous investigations over the past decades. The conventional modal analysis could not be  applied on nonlinear continuous system which makes it impossible to construct the reduced order models and obtain system response based on limited number of measurement points. Nonlinear normal modes provide a useful tool for extending modal analysis to nonlinea...

In this paper, static response and buckling analysis of functionally graded saturated porous beam resting on Winkler elastic foundation is investigated. The beam is modeled using higher-order shear deformation theory in conjunction with Biot constitutive law which has not been surveyed so far. Three different patterns are considered for porosity distribution along the thickness of the beam: 1) ...