TMMOBABSTRACT: The slope stability of rock masses which the engineering constructions build on is controlled by thestrength parameters of discontinuity surfaces rather than shear strength parameters of rock bodies. Inaddition, it is known that the aperture, persistence, roughness, and if it presents, thickness and type of infill materials are the major parameters which control the strength of discontinuities. In this study, theshear strength parameters of discontinuities in the hornfels lithology in the Doğu Ocak (eastern sector ofBalıkesir-Şamlı-Iron Open Pit Mine) were determined by using the Barton empirical failure criterion. Theprobable rock slope failure modes were established by means of kinematic analyses performed consideringthe orientations and shear strength parameters (cohesion and internal friction angle) of discontinuitysurfaces. It is proposed that the orientation of the slopes are 218° in northern side and 15° in southern sidewhereas bench slopes are 65° and 60° in W3 and W3-W4 weathering zones respectively, in accordancewith the stability analyses performed in the light of the information obtained from the models in the DoğuOcak.
ABSTRACT: Landslide is the most common mass movement in open-pit mines. A serious slope-instability conditionis usually accompanied by gradual development of one or more tension cracks behind or near the crestof the slope, allowing for time-displacement monitoring. Surface-displacement movements employingGPS and other instruments with attendant prompt analysis of slope-movement velocities are usuallyadequate for predicting slope behavior. This study relates to investigate the causes of this phenomenaand monitoring of the slope movements in the landslide area in southeastern side of the Alipaşa openpit albite mine in Karpuzlu/Aydın. In this context, two relations were investigated in order to determineboth the mode of failure of mass movement and the recognition of landslide causes. The first one isbetween the trend and plunge of cumulative surface-displacement movement at each observation pointand dip angle-dip direction values of the foliation planes in gneiss unit. The second is, on the other hand,between the flowing directions of the stream beds in the former topography of the landslide area and dipdirections of the foliation planes located in and nearby of these beds. The affected area from the slide stillthreatens the mining operations. Absolute lateral and vertical movements within the sliding mass in thelandslide area were measured by using GPS. During the monitoring studies, rainfall amounts were alsomeasured and recorded. They have been evaluated in conjunction with the slope movement data. In orderto prevent and control the sliding-movement, the excavations were implemented in the landslide area withthe purpose of decreasing the slope height and the surface water was drained out of the landslide area.Thus, decelerating slope movements and the positive effects of the mitigation measures were attained andmonitored in this study.
ABSTRACT: Toppling is a failure mode observed in rock slopes with parallel and almost vertical discontinuities which are inclined in to the hill. The rock slope excavated in Eocene aged tuffs, is located in the Devgeriş (Samsun) district of Black Sea coast highway, and exposed to discontinuity-controlled failures. As a result of the quarry operation at the northwest side of studied rock slope, some cracks occurred along the direction of J2 (245/80) joint set. Therefore, the kinematic and FEM-based numerical analyses were carried out in order to investigate the possibility of discontinuity-controlled failures. The results of the kinematic analyses showed that toppling failure is possible along the J2 joint set. It was determined that the factor of safety value is 0.86 for the worst condition and 1.23 for current condition when possibility of toppling failure is investigated by numerical analyses. After bolting or slope flattening, the rock slope becomes stable
ABSTRACT: Aggregate has widely used in concrete composition and its properties directly affects the durabilityof concrete. Geological factors such as aggregate type, mineralogy and texture have significant effects onconcrete strength and durability. In this study, granitic rocks collected from different parts of Turkey, havebeen investigated from the point of alkali-silica reactions in concrete. Firstly, mineralogical, petrographicand chemical characteristics of granitic rocks were investigated. Then, accelerated mortar bar testswere performed on these granite samples. The effects of alkali-silica reactions were also investigatedby scanning electron microscope (SEM). According to results obtained, granites, when used as concreteaggregate, are not generally found to be potentially dangerous for alkali-silica reactions.
ABSTRACT: Many studies have been carried out in recent years on estimating consolidation properties of claysfrom their plastic and index properties, and to prefigure about consolidation behaviour of soils. The simpleempirical equations between these parameters can be calculated and applied to specific soil types easily,thus saving time on estimating the consolidation properties of soils prior to detailed laboratory tests.Although there are quite a number of studies presented in the literature, most of these studies have beendone on pure clays (e.g. glass clay), which restrict the applicability of the calculated equations. In thisstudy, a different approach was applied to the clayey soils near Cevizdere region in Ünye (Ordu, Turkey),and the consolidation properties via standard one dimensional consolidation (oedometer) test, Atterberglimits, specific gravities, grain size distribution via wet sieve analysis and hydrometer tests, and the typeof clay minerals via X-ray diffraction (XRD) analyses of 15 natural soil samples were determined. Thesoil samples overall consist of 28 % sand-sized, 38 % silt-sized, and 34 % clay-sized particles. The liquidlimits of the samples vary between 63 % and 76 %, and plastic limits between 24 % and 34 %. Accordingto the IAEG (1976) plasticity classification, the soil samples are classified as highly-very highly plastic.The XRD analyses show the clay minerals in the soil samples are of montmorillonite type. The oedometertest results indicate that the soil samples have compression index (Cc) values ranging between 0.189and 0.625, re-compression index (Cr) values ranging between 0.011 and 0.041, and over-consolidationratio (OCR) values ranging between 4.16 and 95. The studied soil is classified as moderately-highlyover-consolidated according to the over-consolidation limit classification. The pre-consolidation stressesand liquid limits of the soil samples were investigated statistically and the coefficient of correlation iscalculated as 0.5
ABSTRACT: The Sarma Stream is located in southwest of Akcakoca town in Duzce City, Turkey. Its drainage basin is approximately 121.2 km2 . The Sarma stream flows muddy in to the Black Sea with an output of 85 l/s during rainy season . It was decided that the Sariyayla reservoir should be built on the Sarma Stream for the drinking water needs of Akcakoca. Chemical compounds in natural water are altered by interactions with geologic units, by physical and chemical weathering and environmental factors. Generally, research on acid rain and its effect has been done in Istanbul. In this study, effects of acid rainfall on the hydrogeochemistry of the Sarma stream water were investigated. Therefore, samples of rock, soil, rainfall, stream water, suspended and bed sediments were taken in the Sarma Stream basin. The pH of rainfall and snowmelt in the research area are below 5.6. Acid rain affects the dissolution of the geological units and the abundance of principal ions in stream water. The Chemical Index of Alteration (CIA) values of the bed sediment sample and suspended sediment sample are 76 and 77, respectively. Sandstone, which erodes easily and is rich in clay minerals, causes the Sarma Stream to become muddy during the rainy season. The suspended sediment amount of the Sarma Stream in the rainy season is 70 mg/l. The water of the Sarma Stream is rich in calcium and bicarbonate. Rain water is richer in NH4, NO3 and SO4 ions than snowmelt. Snowmelt is richer than rain water in heavy metals such as Al, Ba, Cu, Pb, Mn, Ni, Si, U and Zn. The concentration of heavy metals and some elements such as Al, Ba, B, Fe, Mn and Zn are 10 ppb and more in rain, snowmelt and stream water. Some ions in the Sarma Stream basin waters exceed the drinking indicator water limit values (e.g. Al, Fe and Mn ions). Hence, water in the Sariyayla Reservoir might need to be treated