Engineering geological characterization of volcanic rocks of ethiopian and sardinian highlands to be used as construction materials

However, their relatively higher water absorption and porosity limit them not to be used in public walkways, horizontal pavements, public car parks and flooring in supermarkets in an open environment as intensive use while some flow layers of the basalts are mainly suitable for production of coarse aggregates for cement concrete mix. The Sardinian project area is part of the Plio-Quaternary volcanic rocks that covered the north western central plateaux of the island forming flat topped land feature. The studied area is specifically covered with the †˜Basalti di Plateau†� consisting of porphyritic basalt, vesicular basalt, andesitic basalt and trachybasalt. The physical and mechanical tests conducted on these rocks proved the high potential of the studied rocks to be used in the construction industry. The Uniaxial compressive strength ranges from 35 to 177MPa, Ultrasonic P-wave velocity from 4143m/s to 6066m/s, Water absorption from 1.51 to 3.11%, Porosity from 0.64 to 10.33%, Specific gravity from 2.26 to 2.71, Bulk density from 2.2 to 2.69g/cm3, Abrasion Resistance(Capon wheel) from 19.4 to 23.6mm, Point Load index from 1.98 to 7.05MPa, ACV from 19 to 46%, LAAV from 17 to 33%, Dynamic Young's Modulus from 33GPa to 92GPa to mention a few test results. Furthermore, Alkali Silica Reactivity test, X-ray diffraction analysis and detail petrographic studies were conducted on the collected Sardinian samples. According to the Alkali Silica Reactivity test, a sample is found to be deleterious (highly reactive) and later XRD analysis and petrographic study also confirmed the Alkali Silica Reactivity test result. The Sardinian samples have