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This paper discusses the engineering geological investigations, engineering properties of the rock mass at the dam site, and construction materials for the dam embankment. Kandil Dam is located in Kahramanmaras southeastern Turkey. It is used for energy production and water storage for irrigation. Engineering geological mapping, analysis of the discontinuity system, drilling, trial pitting, Lugeon water pressure tests and laboratory tests were undertaken. As a result of site survey and test results, three pervious and one impervious material quarries were identified. Rock mass classifications were performed in accordance with Rock Mass Rating (RMR) systems for the diversion tunnel. Bedrock in the foundation consists of amphibolites rated by the RMR method as 'good rock'. Based on evaluation of the site and laboratory data, two different quarries were selected for embankment fill materials. In addition, one impervious material quarry was located for cofferdam construction. [ABSTRACT FROM AUTHOR]

This paper describes the cut slope stability problems of southern engineered slopes along 57 km long Mersin-Tarsus Motorway. While the northern slopes were slipping during and following construction, the stability problems occurred at southern slopes after heavy rains in December 2001. The most recent slope stability problem took place on chainage at the km 10+800 embankment on 9 April 2009. About 3.62 × 10 m soil materials have currently slipped at 60 different location. After the occurrence of slides, different remedial methods (reshaping slopes, soil improvements, etc.) have been applied to stabilize the slipped slopes. The slope stability studies were carried out using back analysis to determine the slope failure mechanisms and to estimate effective shear strength parameters. Pore water pressures increase following intense rainfall events and cause reduced resistance to shear strength at the engineered slopes. In addition, the affects of the static and dynamic parameters to analyse the state of the slope after excavation were investigated and possible remedies to improve the state (toe rockfill and retaining wall) were assessed for motorway slopes through determining the slope stability with water parameter and seismic loading, separately and together. The results of the stability analysis have exhibited that a good drainage system and retaining wall prevents the motorway slope slides. [ABSTRACT FROM AUTHOR]

The article discusses the paper on geographical information system (GIS)-based kinematic slope instability and slope mass rating (SMR) maps as an application to a railway route in Sivas, Turkey. It shows the potential use of kinematic stability and SMR maps using a GIS. However, there is a debate on several aspects in the paper about the SMR geomechanical maps elaboration. The paper's authors explained that SMR is a slope geomechanical classification based on Bieniawski's classification. It is believed that the use of continuous slope mass rating instead of original discrete functions for the elaboration of SMR maps can considerably simplify the implementation of SMR through a GIS.

Grouting is one of the most popular methods used to control water leakage in dam constructions. The geological and engineering geological properties of the rock/soil to be grouted are important parameters influencing the design of the grouting. In this study, the geotechnical properties of Deriner Dam's foundation rock and the grouting procedure used for it were investigated to ascertain its suitability for grouting. Detailed investigations were conducted to unravel the reasons for and types of foundation grouting applications used on the main rock in Deriner Dam. The materials used in the grouting and the grouting pressures employed were investigated onsite, and the results obtained are presented in this paper. [ABSTRACT FROM AUTHOR]

The paper reports a study of the surface and ground water in Solaklı Basin, Trabzon, from an assessment of 33 sampling points. Many of the parameters analysed are only marginally acceptable as potable water, even though the samples were collected during the wet season. The highest concentrations of contaminants were found downstream of the centres of population. The results indicate regular monitoring is required and some measures should be taken to protect the limited resources. [ABSTRACT FROM AUTHOR]

The paper highlights the importance of establishing an appropriate database of information to assist planners in site selection and decisions regarding land usage. Such a database should include geological and geotechnical information, but this should be assessed from a geoenvironmental viewpoint. The city of Gumushane in the Black Sea region is discussed, as this area is close to the North Anatolia Fault Zone and there is a shortage of 'suitable' ground for development. [ABSTRACT FROM AUTHOR]

In urban areas, the use of pre-support in shallow tunnels is increasing in order to improve the excavation stability and reduce ground settlements induced by the tunneling. This paper describes the effects of pipe roofing on surface settlements and evaluates the settlements associated with the twin tunnels in the Istanbul metro in terms of numerical, semi-empirical and measured values. FLAC3D was used for the numerical modeling and the method suggested by Herzog for the semi-empirical solution. The numerical results indicate that the tunnel roof formed by the pipe roofing provides a restraining effect, reducing deformation and ground surface settlement by up to 65 %. Herzog's model yields higher maximum surface settlements than those observed. When modified to include the effect of pipe roofing and the distance between the pipes however, there is good agreement between the direct measurements and the values predicted by the numerical and modified Herzog models. [ABSTRACT FROM AUTHOR]

The paper reports a study to assess the relationship between slake durability indices and uniaxial compressive strength, Schmidt hardness, P-wave velocity, modulus of elasticity, effective porosity, water absorption and dry and saturated unit weight for seven types of carbonate rocks obtained from south west Turkey. It was found that the dry unit weight, saturated unit weight and Schmidt hardness gave the best relationship with first cycle slake durability ( r = 0.99) while uniaxial compressive strength has a strong relationship with fourth cycle slake durability ( r = 0.94). The results showed little difference in the correlation coefficients obtained after the fourth cycle. It is concluded that, for the rocks studied, the first and fourth cycles provide sufficiently good data on the durability for preliminary engineering/design works and that the second to fourth cycle results could be estimated using the first cycle slake durability index ( r = 0.99-0.97). [ABSTRACT FROM AUTHOR]

Concrete faced rock-fill (CFR) dams are now very popular. The structural complexity of these dams and the high risk associated with the social and environmental consequences of failures require very reliable analyses of their performance, especially as regards seismic loading. In this paper, a dynamic analysis procedure for CFR dams is proposed and described, using the Damlapınar CFR dam as a case study. The acceleration time history and maximum horizontal peak ground acceleration values were developed based on maximum credible earthquakes over 50 years from nearby seismic sources. Numerical studies showed that the Damlapınar CFR dam will remain stable under the maximum credible earthquake with a peak ground acceleration of 0.15 g. According to the numerical results, earthquake-induced deformations of the dam are expected to be within the safety margins determined by the Ministry of Public Works and Settlement, Turkey. The results also indicate that a non-linear analysis capable of capturing dominant non-linear mechanisms can be used to assess the stability of CFR dams. [ABSTRACT FROM AUTHOR]

The Kayranlik Mountain (Goksun) in Kahramanmaras is a rich resource of an attractive conglomerate with many uses in the construction industry including blocks, shaped stones, pavement, sidewalks and landscape architecture. The paper reports a study to assess their compliance with the relevant Turkish and European Standards and provides correlations between the uniaxial compressive strength, flexural strength, Brazilian tensile strength, water absorption, abrasion and density. [ABSTRACT FROM AUTHOR]

This paper presents the engineering geological properties and support design for a diversion tunnel through diabase at the Kapikaya dam site, eastern Turkey. The rock mass rating and rock mass index were used to determine the support requirements, which were also analyzed using commercial software based on the finite element method. The parameters calculated by the empirical methods were used as input parameters for the FEM analysis and the results from the two methods were compared. It was found that the optimum solution was obtained by using a combination of both empirical and numerical approaches. [ABSTRACT FROM AUTHOR]

Unlike the symmetrical surface settlement trough of a single tunnel which can be described using the Gaussian function, surface settlement over twin tunnels can be symmetric with respect to the mid-point between two tunnels or asymmetric. The paper reports the settlement troughs which developed when earth pressure balance (EPB) machines were used to excavate twin tunnels at shallow depth in the soft ground conditions beneath a developed part of Istanbul. An attempt is made to evaluate the effects of different factors on the surface subsidence. Detailed monitoring was undertaken when one tunnel was advanced ahead of the other and when only one tunnel was being driven. It was found that the shapes of the subsidence troughs over the two tunnels were different and varied with the excavation of the second/subsequent tunnel. It is concluded that changes in the subsidence trough are related to disturbance in the geo-material when an excavation is advanced ahead, as well as the nature and thickness of the overburden. [ABSTRACT FROM AUTHOR]

The Kayranlik Mountain (Goksun) in Kahramanmaras is a rich resource of an attractive conglomerate with many uses in the construction industry including blocks, shaped stones, pavement, sidewalks and landscape architecture. The paper reports a study to assess their compliance with the relevant Turkish and European Standards and provides correlations between the uniaxial compressive strength, flexural strength, Brazilian tensile strength, water absorption, abrasion and density. [ABSTRACT FROM AUTHOR]

Peats consist of the partly decomposed remains of vegetation, which have accumulated in waterlogged areas. They are often unsuitable for supporting structures of any kind due to their high water content, high compressibility, low shear strength and high degree of spatial variability. The paper reports a preliminary study on peats from industrial sites in the city of Kayseri, Turkey. The soils in the study area are classified as peat to muck. The peats are fibrous at shallow depth and become amorphous as they extend to some 8 m depth. The ranges of geo-engineering properties are generally consistent with those reported in the literature, with some variation due to their higher mineral soil contents. The behavior of the peats is essentially frictional, with high friction and relatively small cohesion. The direct shear tests yielded higher shear strengths than those from the triaxial tests, due to the fact that the peat specimens used in the direct shear tests were rich in fibers and mineral soils. Back analysis of the settlement of heavy rolls of metal wires laid on the peat generally confirmed the consolidation properties of the soil determined in laboratory. [ABSTRACT FROM AUTHOR]

Abstract  The paper reports an assessment of the engineering geological characteristics of the rock mass to be encountered between Mecidiye and Gazino stations on the new extension of the Ankara metro and the determination of appropriate support and excavation methods. The rock mass quality was estimated using the rock mass rating (RMR), geological strength index (GSI) and rock mass quality (Q) systems and the tunnel divided into sections. The RMR, Q and NATM systems were used to determine the support and excavation methods in these areas. The deformations and stress concentrations around each tunnel section were investigated and the interaction of the support systems with the rock mass was analyzed using finite element software. It is concluded that rock mass classification systems should be used in tandem with numerical tools, although it is emphasized that the estimation of rock mass properties is not an exact science and both rock properties and numerical models should be refined based on observations and the results of instrumentation installed during the construction of a tunnel. [ABSTRACT FROM AUTHOR]

Abstract  The 1998 Ceyhan (Adana, Turkey) earthquake caused major damage to construction on caliche formations. Caliche (a heterogenous secondary calcium carbonate deposit formed in arid and semi-arid regions) is widespread in the Adana area. The paper distinguishes three types of caliche: massive, containing vegetation remains and containing gravel. The porosity, water absorption and unconfined compressive strength of these three groups of caliche were determined. The compressive strengths are low compared to caliches in other areas—an important consideration as Adana is the fourth largest city in Turkey. [ABSTRACT FROM AUTHOR]

Abstract  The paper summarizes the different modes of failure affecting earth dams as a consequence of earthquake shaking. A case study is presented to illustrate seismic deformation analysis using the Alibey Earth Dam, Istanbul, Turkey as an example. The dynamic behaviour, failure modes and mechanisms of failure of the dam under possible ground motions were investigated. The results from finite element analysis are compared with the experimental study. [ABSTRACT FROM AUTHOR]

Abstract  Each day some 400–450 ton solid waste is dumped on land and in the sea and rivers in the coastal cities of the eastern Black Sea, creating serious environmental problems. The paper reports the engineering geological studies of a proposed landfill site for Trabzon, a major city in the region. Fieldwork included scan-line and seismic surveys as well as boreholes and in-situ testing. Water absorption tests indicated permeabilities in the order of 10−8 m/s. [ABSTRACT FROM AUTHOR]

Abstract  Recent examples show that strong earthquakes can cause damage to dams, notably tailings or hydraulic fill dams or relatively small earth fill embankments. Liquefaction is known to be one of the most dangerous consequences of the dynamic loading of an embankment dam and hence must be considered during the dam site selection and construction stages. This paper presents the liquefaction analyses undertaken for the Demir�z� dam site in Northeast Turkey. The liquefaction assessments are mainly based on field-performance data using SPT- and CPT-based methods in conjunction with the results of the available cyclic triaxial tests. The presence of a very shallow groundwater table, loose sandy layers and the seismic features of the region result in a high susceptibility to liquefaction. The results obtained from the SPT- and CPT-based criteria for evaluating the liquefaction potential are generally consistent and show that the thickness of the liquefiable layers increases in the area between the left bank and the central part of the proposed dam. Further studies are required to evaluate the suitability and efficiency of measures which could be taken to avoid liquefaction-induced problems at the dam site. [ABSTRACT FROM AUTHOR]

Abstract  The paper presents the geotechnical properties along the route of the 9,325 m twin tunnel metro route in the Greater Municipality of Ankara. Convergence measurements taken during tunnel construction are presented and discussed. In addition, the convergence of the twin metro tunnels was analysed by means of a 2D plane strain finite element (FE) analysis. The FE model estimations and the field measurements are compared. [ABSTRACT FROM AUTHOR]