The use of the S-transform in Prazeres clay site
DOI: 10.54647/cebc560120 73 Downloads 99475 Views
Author(s)
Abstract
In the framework of a research project led by the Faculty of Engineering - University of Porto (FEUP), an investigation and characterization campaign was carried out on a profile of the Lisbon Prazeres clay and limestone formation. The campaign comprised the use of in situ P and S-waves seismic cross-hole (CH) tests, using a borehole hammer and a sparker source, as well as mechanical tests such as SPT, PMT and SBPT. In addition, laboratory tests were carried out on undisturbed samples, using bender and ultrasonic transducers prior and during triaxial tests. The fact that two different in situ seismic sources were used allowed a comparative seismic signal analysis in time, frequency and time-frequency domains, using the Short Time Fourier Transform, STFT, and the S-Transform, ST. Following a summarized description of the developed work and obtained direct and indirect results, this paper addresses the analysis and comparison of the referred CH results using the STFT and ST approach.
Keywords
Prazeres Miocene clays, bender and ultrasonic transducers, seismic cross-hole, S-Transform
Cite this paper
Jorge Machado de Carvalho, Mafalda Lopes Laranjo,
The use of the S-transform in Prazeres clay site
, SCIREA Journal of Civil Engineering and Building Construction .
Volume 8, Issue 2, April 2023 | PP. 81-98.
10.54647/cebc560120
References
[ 1 ] | Antunes, M. T., P. Legoinha, P. P. Cunha and J. Pais. "High resolution stratigraphy and miocene facies correlation in Lisbon and Setúbal Peninsula (Lower Tagus basin, Portugal)." Ciências da Terra (UNL) 14: 183-190, 2000. |
[ 2 ] | Zbyszewski, G. "Panorama sur la Geologie de la Ville de Lisbonne." Boletim da Sociedade de Geografia de Lisboa 65, Série (9-10), 1947. |
[ 3 ] | Moitinho de Almeida, F. "Carta Geológica do Concelho de Lisboa". S. G. d. Portugal, Serviços Geológicos de Portugal, 1986. |
[ 4 ] | Stockwell et all. "Localization of the complex spectrum: the S transform". IEEE Trans Signal Process 44: 998-1001, 1996, DOI: 10.1109/78.492555. |
[ 5 ] | Carvalho, J., Fonseca, A.V., Almeida, F., Hermosilha, H. "ISC’2 experimental site investigation and characterization – Part I: conventional and tomographic P and S waves refraction seismics vs. electrical resistivity". Geotechnical and Geophysical Site Characterization, Proceedings of the 2nd International Conference on Site Characterization, ISC-2”, Porto, Portugal, 19-22 September 2004, Viana da Fonseca & Mayne (eds), 2004 Millpress, Rotterdam, ISBN 90 5966 009 9 (pgs. 1361-1369, (pp. 433-441). |
[ 6 ] | Viana da F. A; Carvalho, J.; Ferreira, C.; Santos, J. A; Almeida, F.; Pereira, E.; Feliciano, J.; Grade, J.; Oliveira, A. "Characterization of a profile of residual soil from granite combining geological, geophysical and mechanical testing techniques". Geotechnical and Geological Engineering V24, Nº 5: pp. 1307-1348. (ISSN: 0960-3182, Print, pp.1573-1529, Online).doi: 10.1007/s10706-005-2023-z. ICDS = 10.0.Viana et al., 2006 |
[ 7 ] | Clarke, G. B., Ed. "Pressuremeters in geotechnical design". London, Chapman and Hall, 1995. |
[ 8 ] | Cassan, M. "2Les Essais in situ em Méchanique des Sols. Tome 1: Realization et Interpretation". E. Eyrolles. Paris, Editions Eyrolles, 1978. |
[ 9 ] | Briaud, J. L. "The pressuremeter". Rotterdam, Netherlands, A.A. Balkema, 1992. |
[ 10 ] | Gibson, R. E. and W. F. Anderson. "In situ measurements of soil properties with the pressuremeter." Civil Engineering and Public Works Review 56(658): 615-618, 1961. |
[ 11 ] | Palmer, A. C. "Undrained plane-strain expansion of a cylindrical cavity in clay: a simple interpretation of the pressuremeter test." Géotechnique 22(3): 451-457, 1972. |
[ 12 ] | Ferreira, C. "The Use of Seismic Wave Velocities in the Measurement of Stiffness of a Residual Soil". Civil Engineering, Porto, Porto. PhD Thesis, 2009. |
[ 13 ] | Tallavó, F., G. Cascante and M. D. Pandey. "New Methodology for Source Characterization in Pulse Velocity Testing." Geotechnical Testing Journal 32(6), 2009. |
[ 14 ] | Lopes Laranjo, M. "Argilas Miocénicas de Lisboa. Parametrização para o Dimensionamento de Estruturas Geotécnicas". Civil Engineering, Porto, Porto. PhD Thesis, 2013. |