Experimental and Numerical Observations of the Frequency-Domain Method in Bender-Element Testing

• Type: Article in International Scientific Journal
• Date: 2017-08-01

Authors

A. Viana da Fonseca (Author) FEUP

Journal

The Journal is awaiting validation by the Administrative Services.

Title: JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING

Vol. 143

ISSN: 1090-0241

Indexing

ISI Web of Knowledge - 3 Citations

ISI Web of Science

Scopus - 14 Citations

Scientific classification

CORDIS: Technological sciences > Engineering > Civil engineering > Geotechnics

FOS: Engineering and technology ; Engineering and technology > Civil engineering

Other information

Authenticus ID: P-00M-HDE

DOI: 10.1061/(asce)gt.1943-5606.0001603

Abstract (EN): In bender-element (BE) testing, shear-wave velocities are measured using two main methods: time-domain analysis of vibration data from pulse excitation and frequency-domain analysis of vibration from sine-sweep excitation. The frequency-domain analysis can be performed automatically. However, its results show high variability because they are affected by different variables such as the frequency content of the excitation, the resonant frequency of the BE system, and the resolution of the frequency-domain analysis. The reliability of the frequency-domain method is studied in this paper using simplified mathematical models and experimental results from BEs, miniature accelerometers, and resonant-column (RC) tests. The mathematical models are used to understand the effects of different variables in the frequency-domain method. Both laboratory and numerical results show that amplification peaks in the transfer function of the BE system can significantly affect the estimation of the shear-wave velocity. A modified frequency-domain analysis is proposed to enhance the reliability of the method using a high-frequency narrowband excitation outside the resonant peaks of the BE system. Results from the modified frequency-domain analysis tests show less than 10% error in the measurement of the shear-wave velocity with respect to the RC results.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12