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Stability investigations were conducted for a slope at the back of a borax stockpile site near the Bandirma Harbor in the northwestern Turkey. There was a slope failure at the site causing damage in the concrete sections of the harbour in front. Investigations started with deformation monitoring with an inclinometer. Failure mechanisms were determined with back analysis using method of slices and finite difference models. A combined failure mechanism involving a circular failure surface in the slope and a noncircular part in a weak zone under the stockpile area was found to be responsible for the failures in the region.

Rock samples from the Baglum-Kosrelik area, 30 km north of Ankara, Turkey have been studied petrographically in detail to differentiate between nodular limestones and hardgrounds. However, it is found that petrographic criteria alone may not always be used to differentiate between nodular limestones and true hardgrounds. Distinction between hardgrounds and other wellindurated carbonate rocks can be made based upon the strength properties of the rocks, including uniaxial compressive strengths, triaxial compressive strengths, modulus ratios, and elastic constant ratios. This study showed that rock petrophysical characteristics could be used to develop criteria for distinguishing hardgrounds. For example, strength tests using the International Society for Rock Mechanics result in very high strength and extreme hardness values, with a minimum uniaxial compressive strength value, of 130 MPa with 10% standard deviation, therefore the rock can be classified as “true” hardground. Classification of these carbonates in this manner would facilitate quantitative discussions between hardground carbonate petrographers and engineering geologists. Hardgrounds throughout the world then could be tested and classified accordingly.

In this paper, performance assessment studies for hydraulic and cable shovels carried out on a nationwide scale in the surface lignite mines of Turkish Coal Enterprises are explained. The work was involved manual stopwatch surveys of shovel dig cycle times, estimation of bucket filling and hourly excavation capacity of shovels. The accumulated data is compared with the literature values in order to be evaluated in terms of ease of digging. The observed bucket size ranges of hydraulic and cable shovels varied from 2,5 to 10.5 and 4.5 to 25 yd respectively. The work efficiencies were established by considering observed and net outputs. Furthermore, the performance results were cooperated with geotechnical data to define the ease of digging.