This paper addresses the problem of quantifying the mechanical contribution of rockbolts installed systematically around tunnels (regularly spaced around the tunnel) excavated in rock masses. Assuming that the mechanical contribution of grouted rockbolts is that of increasing internal pressure within a broken rock mass, a new procedure for computation of ground response curves for a circular tu...

Probabilistic seismic hazard analysis is a technique for estimating the annual rate of exceedance of a specified ground motion at a site due to the known and suspected earthquake sources. A Monte-Carlo approach is utilized to estimate the seismic hazard at a site. This method uses numerous resampling of an earthquake catalog to construct synthetic catalogs to evaluate the ground motion hazard a...

near-fault ground motions with long-period pulses can place severe demands on structures near an active fault. these pulse-type ground motions can be represented by pulse sequences with simple shapes. half-sinusoidal pulse sequences are used to approximate recorded ground motions and dynamic responses of sdof system under the excitation of these pulse sequences are studied. four cases are consi...

The Hartley transform, a real-valued alternative to the complex Fourier transform, is presented as an efficient tool for the analysis and simulation of earthquake accelerograms. This paper is introduced a novel method based on discrete Hartley transform (DHT) and radial basis function (RBF) neural network for generation of artificial earthquake accelerograms from specific target spectrums. Acce...

Characteristics of ground motions close to the earthquake source can be considerably different from those of far-field motions which should be considered in design process of structures. The current study aimed to present new design response spectra for Iranian seismic design code taking into account the near-fault effects. For this purpose, a new attenuation relation based on the ground motion...

Understanding strong ground motions in the near-fault areas is important for seismic risk assessment in densely populated areas. In the past, lack of information on strong ground motion for large and moderate earthquakes led to the use of mainly far field large and moderate earthquake records in equations for calculation of the strong ground motion parameters. In this article, we collected and ...

Recently, concerning failure of structures due to earthquakes, special investigations of near fault ground motions have been noticed. Hence, in this paper, characteristics of near field ground motions have been considered in horizontal and vertical directions. In this consideration, the record averages have been compared with Uniform Building Code and Eurocode8 spectra in two levels. In additio...

Abstract General faults in regular electrical railways system could be detect by implementing the specific protection functions such as ground fault or sensitive earth fault. Otherwise, in ungrounded electrical railway systems which using both feeding and return contact rail at the same time, fault detection cannot done with above-mentioned function. Due to recent growth in electrical railway ...

has been studied by several authors, where 1 < p for N = 2, 1 < p < (N + 2)/(N − 2) for N ≥ 3 and Q(x) is a positive bounded continuous function. If Q(x) is a radial function, we can find infinity many solutions of problem (PQ) by restricting our attention to the radial functions (cf. [2, 5]). IfQ(x) is nonradial, we encounter a difficulty caused by the lack of a compact embedding of Sobolev ty...