Engineering geological characterization of the Antalya karstic rocks, southern Turkey

This study encompasses engineering geological characterization of the Antalya karstic foundation rocks, particularly tufa, whose mechanical behavior is highly variable. The Antalya tufa rock has no well-developed discontinuity systems. It is variably porous, and is composed of different rock types with variable structures. To reveal the engineering geological parameters and to develop a thorough engineering geological database, which is not available in the literature for the Antalya tufa rock, geological observations, engineering geological site investigations, mineralogical analyses, field (plate load tests) and laboratory geomechanics tests have been performed. The physico-mechanical properties such as porosity, seismic wave velocity, uniaxial compressive strength, Young’s modulus, deformation modulus, tensile strength, cohesion, angle of internal friction and other petrographic characteristics such as organic matter content and rock fabric that are expected to have a significant influence on its behavior were determined. Regression analyses have been performed to obtain relationships between the engineering geological parameters of the Antalya tufa rock. A number of good correlations (R ² ≥ 0.75) obtained by regression analyses indicated that the Antalya tufa rock types could be differentiated better by using the strength parameters (namely, uniaxial compressive and tensile strength) and the index parameters (namely, unit weight and porosity).