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...

In this study, we revealed rapid detection of streptomycin-producing Streptomyces spp. by extraction of total soil DNA from 14 soil samples using a modified lysis method followed by PCR amplification ofa genus-specific sequence in the Streptomyces' 16S rDNA gene. DNA band of the expected size (438 bp) was seen with all the samples. Additionally, specific amplification of the streptomycin-coding...

The average strongto weak-motion amplification ratios during the 1989 Loma Prieta and 1987 Whittier Narrows earthquakes in California are estimated by modeling strong ground motions at soil sites in the linear-response assumption and comparing the simulated and observed records. The linear amplification function, used to synthesize ground motions, is the generic transfer function developed for ...

The need for identification of soil microbial community mainly depends on direct extraction of DNA from soil, a multifaceted environment that is a major pool for microbial genetic diversity. The soil DNA extraction procedures usually suffer from two major problems, namely, inappropriate rupturing of cells and contamination with humic substances. In the present study, five protocols for single t...

Three amplification mechanisms of large accelerations over 20 m/s2 are related to various non-liner behaviors and explained by using the non-stationary Fourier spectra. The frequencies of dominant components are compared with the natural frequencies with the ratios (1:3:5:7) of a shear-spring model of the underground soil. Thus, one of the amplification mechanisms is supposed to result from the...

Chronic wasting disease (CWD) and scrapie can be transmitted through indirect environmental routes, possibly via soil, and a practical decontamination strategy for prion-contaminated soil is currently unavailable. In the laboratory, an enzymatic treatment under environmentally relevant conditions (22°C, pH 7.4) can degrade soil-bound PrPSc below the limits of Western blot detection. We develope...

In this paper, the spectral ratio of mmicrotremor, HSVR, is presented for estimating the liquefaction potential of layered soil in the coastal area of the Persian Gulf, which consists of a hard sandstone layer situated between two saturated sandy layers. The surface layer is thin, with a thickness between 2 and 5 meters. The purpose of this paper is to identify the relation between the liquefac...

Millions of financial losses and thousands of people which die are due to earthquakes that happen every now and then in all corners of the world. Safety against the hazards of earthquake relates to two basic factors: safety of the structure and site. Site's conditions play an important role in damages of structures. This factor has a geotechnical cause and could be appeared as seismic wave ampl...

The mechanism of earthquake energy input to building structures is clarified by considering the surface ground amplification and soil-structure interaction. The earthquake input energies to superstructures, soil-foundation systems and total swaying-rocking system are obtained by taking the corresponding appropriate free bodies into account and defining the energy transfer functions. It has been...