The dynamic response of an initially flat viscoelastic membrane is investigated. The viscoelastic model is described with fractional order derivatives. The membrane is subjected to surface transverse and inplane dynamic loads. The governing equations are three coupled second order nonlinear partial FDEs (fractional differential equations) of hyperbolic type in terms of the displacement componen...

Retrofitted bridge fragility curves provide a powerful tool for assessing the effect of retrofit measures on the seismic performance of different bridge types under a range of loading levels. Traditional methods for retrofit assessment typically evaluate the effectiveness of retrofit based on the performance of individual components. However, the use of fragility curves for retrofitted bridges ...

Guidelines for seismic spectral amplification are provided in current building codes based on soil strength/stiffness by means of seismic site class. However, current codes do not make a difference between fully saturated and unsaturated soil deposits and do not account for effects of soil heterogeneity on seismic amplification. This study investigates the effect of natural small scale soil het...

The object of this paper is the evaluation of the seismic response of reinforced concrete frames designed according to the DDBD (direct displacement-based design) approach. The great part of research works about DDBD has been dedicated to planar frames, but recently also some proposals for 3D structures have been presented, in particular for wall structures. This paper will give a further contr...

A damage-based approach for the performance-based seismic assessment of reinforced concrete frame structures is proposed. A new methodology for structural damage assessment is developed that utilizes response information at the material level in each section fiber. The concept of the damage evolution is analyzed at the section level and the computed damage is calibrated with observed experiment...

Seismic design procedures in current building provisions are based on linear and nonlinear static approaches that use capacity-demand index relationships such as the relationship between the lateral strength and the maximum lateral displacement. Previous research on the development of these relationships is based on linear-elastic ground motion acceleration response spectra, whereas the current...

After learning from several devastating earthquakes in China in recent years, stricter design criteria have been introduced in the current Chinese seismic design code. To investigate the reliability of the current seismic design code, seismic fragility analyses were performed for 45 10-story reinforced concrete (RC) frame-shear wall structures designed according to the current Chinese seismic d...

Yielding elements (YE) are among those devices that not only help control structural damages, but make better seismic behavior by concentrating the frames in some removable part of the structures. YE are located at the intersection of Concentric Braced Frame (CBF) in a rectangular shape. In this paper, Seismic behavior of the frames with YE will be investigated. For this reason, 5 braced steel ...

hysteretic dampers as the most practical passive control methods have improved the seismic performance of steel structures through energy dissipation induced by large inelastic deformations. among them in this paper, kbf (knee braced frames), a special form of braced frames having a diagonal brace connected to a knee element instead of beam-column joint, is investigated. in such systems, the kn...

SUMMARY The quality of seismic-to-well tie is commonly quantified using the classical Pearson's correlation coefficient. However the seismic wavelet is time-variant, well logging and upscaling is only approximate, and the correlation coefficient does not follow this nonlinear behavior. We introduce the Dynamic Time Warping (DTW) to automate the tying process, accounting for frequency and time v...