Download or read book Analytical Study of the Spectral analysis of surface waves Method at Complex Geotechnical Sites written by Jeffrey D. Bertel and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Spectral-Analysis-of-Surface-Waves (SASW) method is an accepted means of measuring shear wave velocity (VS). In some settings, SASW measurements have produced results that were inconsistent with results from other methods of measurement. The effectiveness of the SASW methodology at complex geotechnical sites was investigated to identify site conditions where the SASW approach may produce erroneous results. Analytical simulations of surface wave measurements were performed. A traditional SASW methodology (global analysis), and a more rigorous approach (array analysis) were used to generate experimental dispersion curves. The effectiveness of these approaches was evaluated by comparing the experimental results to the true dispersion curve. The global analysis yielded dispersion curves that tend to underestimate surface wave velocities at long wavelengths. The array approach worked well for both simple, gradually increasing VS profiles as well as for some complex profiles with large VS contrasts. In some cases both the global and array analysis produce an experimental dispersion curve that is not consistent with the theoretical dispersion curve, especially for soft-over-stiff profiles, a common profile encountered in the field. These results have implications for earthquake site response analysis.
Download or read book SASW Measurements at Geotechnical Sites Overlaid by Water written by JM. Roesset and published by . This book was released on 1994 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Spectral-Analysis-of-Surface-Waves (SASW) technique is a nonintrusive, nondestructive technique that employs surface waves of the Rayleigh type to determine the layer thicknesses and stiffnesses of subsurface profiles. The SASW technique has been developed and successfully used on land. This paper extends the method to sites overlaid by water. A theoretical model has been developed to study the "surface" waves that propagate along a soil-water interface using a half-space overlaid by water as an approximation. The waves at the soil-water interface are termed "Scholte" waves. Results from the theoretical model show that in "deep" water, defined as a water depth exceeding the wave length of the Scholte wave, the effect of water is to reduce the surface wave velocity slightly from the velocity for a similar surface (Rayleigh) wave with air over the surface. Results of experimental studies are also described and shown to compare well with theoretical predictions.
Download or read book Unsaturated Soils Research and Applications written by Claudio Mancuso and published by Springer Science & Business Media. This book was released on 2012-06-26 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: These volumes contain the contributions to the Second European Conference on Unsaturated Soils, E-UNSAT 2012, held in Napoli, Italy, in June 2012. The event is the second of a series of European conferences, and follows the first successful one, organised in Durham, UK, in 2008. The conference series is supported by Technical Committee 106 of the International Society of Soil Mechanics and Geotechnical Engineering on Unsaturated Soils. The published contributions were selected after a careful peer-review process. A collection of more than one hundred papers is included, addressing the three thematic areas experimental, including advances in testing techniques and soil behaviour, modelling, covering theoretical and constitutive issues together with numerical and physical modelling, and engineering, focusing on approaches, case histories and geo-environmental themes. The areas of application of the papers embrace most of the geotechnical problems related to unsaturated soils. Increasing interest in geo-environmental problems, including chemical coupling, marks new perspectives in unsaturated soil mechanics. This book will provide a valuable up-to-date reference across the subject for both researchers and practitioners.
Download or read book Surface Wave Analysis for Near Surface Applications written by Giancarlo Dal Moro and published by Elsevier. This book was released on 2014-11-04 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic Wave Analysis for Near Surface Applications presents the foundational tools necessary to properly analyze surface waves acquired according to both active and passive techniques. Applications range from seismic hazard studies, geotechnical surveys and the exploration of extra-terrestrial bodies. Surface waves have become critical to near-surface geophysics both for geotechnical goals and seismic-hazard studies. Included in this book are the related theories, approaches and applications which the lead editor has assembled from a range of authored contributions carefully selected from the latest developments in research. A unique blend of theory and practice, the book’s concepts are based on exhaustive field research conducted over the past decade from the world’s leading seismologists and geophysicists. Edited by a geophysicist with nearly 20 years of experience in research, consulting, and geoscience software development Nearly 100 figures, photographs, and examples aid in the understanding of fundamental concepts and techniques Presents the latest research in seismic wave characteristics and analysis, the fundamentals of signal processing, wave data acquisition and inversion, and the latest developments in horizontal-to-vertical spectral ratio (HVSR) Each chapter features a real-world case study—13 in all—to bring the book’s key principles to life
Download or read book Experimental study of applying the spectral analysis of surface waves method offshore written by Robert C. Gauer and published by . This book was released on 1990 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of Factors Affecting the Spectral analysis of surface waves Method written by Glenn J. Rix and published by . This book was released on 1991 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Efficient Joint Analysis of Surface Waves and Introduction to Vibration Analysis Beyond the Clich s written by Giancarlo Dal Moro and published by Springer Nature. This book was released on 2020-06-20 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book bridges the gap between theory and practice, showing how a detailed definition of the shear-wave velocity (VS) profile can be efficiently obtained using limited field equipment and following simple acquisition procedures. It demonstrates how surface waves (used to define the VS profile) and vibration data (used to describe the dynamic behaviour of a building) can be recorded using the same equipment, and also highlights common problems, ambiguities and pitfalls that can occur when adopting popular methodologies, which are often based on a series of simplistic assumptions. Today, most national and international building codes take into account a series of parameters aimed at defining the local seismic hazard. Sites are characterised based on the local VS profile, and the dynamic behaviour of existing buildings is defined through the analysis of their eigenmodes. The book includes a series of case studies to help readers gain a deeper understanding of seismic and vibration data and the meaning (pros and cons) of a series of techniques often referred to as MASW, ESAC, SPAC, ReMi, HVSR, MAAM and HS. It also provides access to some of the datasets so that readers can gain a deeper and more concrete understanding of both the theoretical and practical aspects.
Download or read book Surface Wave Methods for Near Surface Site Characterization written by Sebastiano Foti and published by CRC Press. This book was released on 2014-08-21 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Develop a Greater Understanding of How and Why Surface Wave Testing WorksUsing examples and case studies directly drawn from the authors' experience, Surface Wave Methods for Near-Surface Site Characterization addresses both the experimental and theoretical aspects of surface wave propagation in both forward and inverse modeling. This book accents
Download or read book Geotechnical and Geophysical Site Characterization 4 written by Roberto Quental Coutinho and published by CRC Press. This book was released on 2012-09-06 with total page 1888 pages. Available in PDF, EPUB and Kindle. Book excerpt: Site characterization is a fundamental step towards the proper design, construction and long term performance of all types of geotechnical projects, ranging from foundation, excavation, earth dams, embankments, seismic hazards, environmental issues, tunnels, near and offshore structures. Geotechnical and Geophysical Site Characterization 4 provides practical applications of novel and innovative technologies in geotechnical and geophysical engineering, and is of interest to academics, engineers and professionals involved in Geotechnical Engineering.
Download or read book Wind and Seismic Effects written by United States-Japan Cooperative Program in Natural Resources. Panel on Wind and Seismic Effects. Joint Meeting and published by . This book was released on 1994 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geophysical Characterization of Sites written by Richard D. Woods and published by Science Publishers. This book was released on 1994 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental study of factors affecting the spectral analysis of surface waves method written by Glenn Jay Rix and published by . This book was released on 1988 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of the Spectral Analysis of Body Waves SABW Method for Downhole Seismic Testing with Boreholes Or Penetrometers written by Changyoung Kim and published by . This book was released on 2012 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Downhole seismic testing and seismic cone penetration testing (SCPT) have shown little change since the 1990s, with essentially the same sensors, sources, test procedures and analytical methods being used. In these tests, the time differences of first-arrivals or other reference points early in the time-domain signals have been used to calculate shear and compression wave velocities in soil and rock layers. This time-domain method requires an operator to pick the first arrival or other reference point of each seismic wave in the time record. Picking these reference points correctly is critical in calculating wave velocities. However, picking these points in time records is time consuming and is not always easy because of low signal-to-noise ratios, especially in the case of shear waves which arrive later in the time record. To avoid picking reference points, a cross-correlation method is sometimes applied to determine travel times of the seismic waves, especially in traditional downhole testing. One benefit of the cross-correlation method is that it can be automated. The cross-correlation method is not, however, appropriate for evaluation other body wave characteristics such as wave dispersion and material damping. An alternate approach is to use frequency-domain analysis methods which are well suited for evaluating time changes between all types of waveforms measured at spatially different points. In addition, frequency-domain methods can be automated and attenuation measurements can also be performed. Examples of such testing procedures with Rayleigh-type surface waves in geotechnical earthquake engineering are the Spectral-Analysis-of-Surface-Waves (SASW) and Multi-Channel-Analysis-of-Surface-Waves (MASW) methods. In this research, an automated procedure for calculating body wave velocities that is based on frequency-domain analysis is presented. The basis for and an automated procedure to calculated body wave dispersion is also presented. Example results showing shear wave velocity and material damping measurements in the SCPT are presented. The objective of this study is to improve downhole seismic tests with boreholes, cone penetrometers or flat-plate dilatometers by developing a frequency-domain analysis method which overcomes many of the disadvantages of time-domain analyses. The frequency-domain method is called the Spectral-Analysis-of-Body-Waves (SABW) method. The SABW method does not require an operator to pick the first-arrival or other reference times. As a result, the shear wave velocities and wave dispersion can be calculated in real time using the interpretation method with an automatic calculation procedure, thus reducing human subjectivity. Also, the SABW method can be used to determine additional information from the dispersion curves such as the material damping ratio and an estimate of soil type based on the dispersion relationship. In this research, field SCPT measurements are presented as an example to illustrate the potential of the SABW method. Measurements with shear waves are highlighted because these measurements are most often required in geotechnical earthquake engineering studies.
Download or read book Detection of Subsurface Cavities Using the Spectral analysis of surface waves Method written by Naser Abdul-Rahman Al-Shayea and published by . This book was released on 1994 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geotechnical Site Characterization Using Multi channel Analysis of Rayleigh and Love Waves written by James David Lane and published by . This book was released on 2009 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Multi-Channel Analysis of Surface Waves (MASW) is a technique in which surface waves can be analyzed to determine soil shear wave velocity profiles with depth. The shear wave velocity of soil can be used to calculate the shear modulus, which is an important geotechnical engineering parameter. Site surveys were conducted and analyzed located at a location on the flood plain of the Tennessee River. The flood plain consists of a thin layer of soil above rigid (Knox Dolomite) bedrock and exhibited strong stratification. Three different aspects of MASW data acquisition and analysis are presented in the study. The first aspect is the response correction of the classical horizontal and vertical component geophone and its effects on surface wave dispersion; the second aspect is the effect of Rayleigh wave MASW data acquisition, analysis, and modeling as influenced by Rayleigh wave guides; the third aspect is the use of MASW and Love wave data acquisition, analysis, and modeling. MASW is performed using a seismic source and geophones (velocity sensor) without correcting the amplitude and phase errors induced by the equivalent single degree of freedom response function representing the mechanical response of a given velocity sensor. Geophones were experimentally tested in the laboratory to determine their natural frequency, damping ratio, and transduction constants. The results from these tests were mathematically corrected for their mechanical response and compared to uncorrected and corrected field data. Several seismic sources and various sourceoffset distances were evaluated to determine their effects on Rayleigh wave dispersion. Rayleigh waves, guided in a layer, were interpreted to have a profound influence on the Rayleigh wave dispersion data obtained using different seismic sources and source-offset distances. Results from Love wave data analysis produced superior dispersion data in comparison to the dispersion data obtained from Rayleigh wave data, making interpretation much more certain.
Download or read book Theoretical Investigation of the Spectral analysis of surface waves SASW Technique for Application Offshore written by Mahmoud Sedighi Manesh and published by . This book was released on 1991 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and theoretical studies in support of implementing the spectral analysis of surface wave SASW method offshore written by Brent Lyndon Rosenblad and published by . This book was released on 2000 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:
