Geotechnical features of the welded ignimbrites of the Canary Islands

Abstract

First geotechnical data of two pyroclastic deposits are provided: The Arico (Tenerife) and Arucas (Gran Canaria) welded ignimbrites. Average data are summarized for different coloured specimens. Ultrasonic wave velocity varies between a maximum of 4741 m/s and a minimum of 2316 m/s for the Arucas ignimbrites and a maximum of 4865 m/s and a minimum of 3041 m/s for the Arico ones. Bulk density ranges from 1.4 gr/cm3 to 2.4 gr/cm3 (Arucas) and from 1.7 gr/cm3 to 2.4 gr/cm3 (Arico). Uniaxial compressive strength varies from 92.40 MPa to 6.12 MPa (Arucas) and from 127 MPa. to 22.5 MPa (Arico). Tensile strength ranges from 51 MPa to 50 MPa (Arucas) and from 36 MPa to 20 MPa (Arico). Point Load Test gives values from 8 MPa to 0.6 MPa (Arucas) and from 8.2 MPa to 1.7 MPa (Arico). Additionally, the effect of the textural anisotropy is considered.