Reza S. Jalali

University of Guilan · Department of Civil Engineering

Citation: Abbasgholiha, H.; Gičev, V.; Trifunac, M.D.; Jalali, R.S.; Todorovska, M.I. Collapsing Abstract: The sequence of collapsing stages of buildings during strong earthquake shaking is still a poorly understood phenomenon. This study aims to use numerical simulations to improve our understanding of the sequence of phenomena that accompany the...

We present a simple nonlinear model of a shear-beam building that experiences large nonlinear deformations and collapse when excited by large pulses of strong earthquake ground motion. In this paper, we introduce the model and show that its properties can be selected to be consistent with the damage observed in a seven-story hotel in San Fernando V...

A simple model of a three‐span, simply supported bridge consisting of three rigid decks supported by two axially rigid piers and rigid abutments at two ends is analyzed by solving the dynamic differential equations. The response spectrum method is not considered, and it is assumed that there is no soil–structure interaction. The bridge is acted upo...

We present examples of a controlled numerical experiment that contribute towards understanding of the physical phenomena that lead to the reduction of coherency of strong earthquake ground motion. We show examples for separation distance of 100 m between the two points on the ground surface, which is in the range of engineering interest. Our exampl...

The response of structures with large plan dimensions depends on the wave motion beneath their extended or multiple foundations. In addition to translational components of motion, which are different at the base of each column, or at different points of large foundations, point rotations at the base of individual foundations—as well as cord rotatio...

Elastic site response analysis in cross-anisotropic deposits has been elaborated due to incidence of inclined SH wave front. A site consisting of a single cross-anisotropic soil layer rested on a half-space representing the bedrock is examined, subjected to inclined SH wave and the out-of-plane displacement amplitude is obtained by assembling the d...

A two-dimensional model of a building supported by a rectangular, flexible foundation embedded in the soil is analysed for excitation by an incident SH-wave pulse. The building and foundation are assumed to be linear while the soil can experience nonlinear deformations. Work expanded on the development of nonlinear strains in the soil can consume a...

The research, presented in this paper, aims to investigate the behavior of a High-Strength Steel Fiber-Reinforced Concrete (HSSFRC) mesoscopic finite element model at compressive high strain rates. In order to produce a three-dimensional meso-scale finite element model, a computer code is developed to randomly produce mesoscopic models of SFRC spec...

The plane-wave assumption for incident SH waves can be a good approximation for cylindrical and spherical waves radiated from finite sources, even when the source is as close as twice the size of the inhomogeneity, and when the source and the inhomogeneity are described within the same coordinate system. However, in a more general setting, and when...

In this study a simple model of one and two-storey adjacent buildings excited by the horizontal and vertical components of fault-normal pulse and fault-parallel displacement with different magnitudes and time lags has been considered. In the considered model each storey consist of a rigid beam connected to two axially rigid mass-less columns by non...

Linear and non-linear responses of a two-story structural model excited by near-source fault-normal pulse and fault-parallel displacement are investigated. For the considered linear system, the multi-component differential-motion effects amplify the first-story drifts 3.0–4.0 times relative to the excitation by synchronous horizontal ground motion...

Wave passage and differential motions of long structures can lead to excessive demands in the near field of strong earthquakes. For long and stiff structures these demands are dominated by pseudo-static deformations resulting from differential ground motions. In our previous work we confirmed that replacing continuous bridge girder with multiple sh...

The impact force response spectrum between two adjacent linear structures excited by fault-normal pulse and fault-parallel displacement with different magnitudes has been considered. Both structures have been modelled by single-degree-of-freedom systems and pounding has been simulated by the non-linear viscoelastic model. The system of coupled equa...

Elementary consequences of the wave-passage effects are described for out-of-plane response of long structures, excited by SH wave earthquake ground motion pulses propagating along their longitudinal axis. For the passage times in the range of 0.005–0.10s, the maximum column drifts can increase several folds due to the combined action of out-of-pla...

In Jalali and Trifunac (2009), the section PSV Spectra at Short Periods contains errors in equations (12), (13), (14), and (15), and in two places within the text. PSVT→∞ should have been PSVT→0. The affected section is reprinted here, with corrections. Full references for citations within this erratum can be found in the original article.

It is shown that the pseudorelative spectral velocity (PSV) of an equiva-lent oscillator, which can be represented by a single degree-of-freedom system for excitation by synchronous horizontal excitation, can be extended to describe the PSV spectra of the same oscillator when excited by simultaneous action of horizontal, vertical, and rocking compo...

Strength-reduction factors are analyzed for simplified near-fault, fault-normal and fault-parallel strong-motion displacements. It is shown that the common design rules for selection of the strength-reduction factors are conservative and properly describe the reduction amplitudes near faults of strong earthquakes, for fault-normal pulses. However,...

Wave-passage effects are described for strength-reduction factors near faults, for fault-normal and fault-parallel strong-motion displacements. It is shown that the common design rules for selection of the strength-reduction factors are usually conservative and approximately describe the reduction amplitudes near faults of strong earthquakes for fa...

The effects of differential motions on strength-reduction factors are described for the structures subjected to propagating horizontal, vertical, and rocking near-source, fault-normal, and fault-parallel strong-motion displacements. It is shown that the common design rules for selection of the strength-reduction factors are not conservative for bot...