ABSTRACT:The aim of this study is to investigate the causes of the landslide occurred on 18 February 2013 at the NW–facing slope of the Harmandalı waste disposal site located in İzmir–Çiğli a n d the reactivation potential of the same circular slip surface. In the light of the geological a n d geotechnical studies resumed in September–2016; the reactivation potential has been evaluated. An embankment (a barrier) was built as a protection structure in front of the slopes of solid waste in 2010. It was determined from the readings in the inclinometer boreholes drilled right after the landslide that the sliding slowed down gradually after the initial landslide. A 64.5 mm displacement occurred in horizontal direction towards NW along the circular slip surface passing through the high plasticity clay band located under the embankment. This movement caused cracks on the walls of the administration buildings, disruption of the main connection road, a n d deformation such as buckling indicating the effect of compression within the embankment. The longitudinal cross-section showing the sliding mechanism has been prepared basedon the pressuremeter tests a n d the readings taken from the inclinometer boreholes drilled at different locations in March–2013 a n d September–2016. In addition, the engineering properties of high plasticity clays (CH), which are the weathering products of the andesitic tuffs that cause sliding, have been investigated.

ABSTRACT:In order to minimize the disaster risk caused by earthquakes, not only province a n d district-based studies, but also studies covering small areas such as neighborhoods a n d villages should be carried out. In this study, Abdurrahmangazi Neighborhood, one of the districts that was severely damaged by two earthquakes that took place on 23 October a n d 09 November 2011 in the province of Van, was examined. The building conditions a n d the ground conditions in the study area where the quarter is located have been considered together. Shear wave velocity (Vs) was used to determine the dynamic behavior of soils. The borehole data obtained in the study area were evaluated a n d the shear wave velocities were determined by using 5 different empirical relations developed by some researchers for the relationship between SPT-N a n d Vs. Using these, VS(30) values were determined a n d ground classifications were made according to the National Earthquake Hazard Reduction Program (NEHRP-2000), EUROCODE-8, the Regulation on Buildings to be Built in Earthquake Zones (DBYBHY-2007). In addition, the new earthquake regulations is Turkey Earthquake Building Regulations (TBDY-2018) were also considered. The building damage conditions a n d the ground conditions in the area where the quarter is located were evaluated together. It was determined that the building damages after earthquakes were caused by structural deficiencies a n d building quality for this neighborhood, regardless of the ground conditions, a n d damage distributions were interpreted accordingly.

ABSTRACT:The gravity data used in this study were taken from the Earth Gravity Model (EGM08) to investigate the crustal structure in the mid-Black arc region. In this study, geological structure boundaries that offer differences in density were tried to determine in the mid-Black arc region. For this purpose, the possible geological structure limits at the basement levels were especially focused on. For this reason, horizontal gradient a n d tilt angle techniques were practiced to find possible geological structure limits using first vertical derivative data of the regional gravity data of the region. The soft-hard sediment, basement, Conrad a n d Moho interfaces have been determined using the radial mean amplitude spectrum of Bouguer data of study region. The topographies of these interfaces were also presented utilizing the Parker-Oldenburg algorithm. Depth values found by inversion calculations for soft-hard sediment, basement, Conrad a n d Moho interface topographies are changed as 0.7-3.5, 2.1-7.4, 9.1-14.2, a n d 35.1- 42.5 km, respectively. The linearities determined in the study were matched against to substantial faults of region. It has been observed that there is a qualitative relationship between the faults, ore deposit a n d earthquake epicenters in the region. The results of this practice were based on studies such as exploring the ore deposits a n d investigating the risks of earthquakes in the future.

ABSTRACT: This study includes the investigation of the quality of agricultural soils a n d groundwater in the plains located in the east of Söke Plain in Aydın province in Western Anatolia a n d the detection of its effect on human health. The rocks belonging to the Menderes Massif form the basis of the geological structure in the study area a n d surrounding.Metamorphic rocks composed of gneiss, granitoid a n d rocks outcropping in the region are essential parameters determining the water a n d soils’ chemistry. The total carcinogenic a n d non-carcinogenic health risk values of waters were calculated for dissolved As, B, Ba, Cd, Cr, Cu, Ni, Pb, U a n d Zn. Anthropogenic a n d geogenic inputs that cause groundwater contamination were distinguished. Also, major ions (Ca, Mg, K, Na, Cl, SO4, HCO3) a n d many trace elements (Ag, Al, Co, Fe, Ge, Mn, Pd, Rb, Se, Si, Sr, Ta, Tl a n d V) were analyzed. Collected soil samples were analyzed for As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, U a n d Zn. The elemental enrichment factors of Söke Plain soils were calculated a n d compared with the background values. Carcinogenic a n d non-carcinogenic total health risks, which is occurred by inhalation, ingestion a n d dermal contact of soil, were calculated. Some groundwater contains above-average dissolved uranium a n d arsenic, which are determined to originate from the gneiss unit.In the plain, the abundance of dissolved uranium increases as the depth of groundwater wells rises. Groundwater containing uranium 3 times the limit value (30 µg/L) is consumed for drinking purposes in the Karacahayıt region.Groundwater containing arsenic above the allowed limit in Yeşilköy, Karacahayıt a n d Kisir regions (23.1, 24.1 a n d 61.1 µg/L, respectively) is consumed for drinking purposes. The highest cancer risk for As in groundwater consumed for drinking was found to be 2.07E-03 in Kisir. The highest cancer risk for As in agricultural soil was found to be 2.38E-04 in Sayrakçı. The local people health status who work on soil with health risks a n d consume carcinogenic waters should be investigated, a n d suggestions for the solution should be implemented.

ABSTRACT:Swelling soils which are problematic in terms of geotechnics should be determined in preliminary works a n d appropriate cautions should be taken. The most frequently used method among the cautions to be taken is to stabilize soil with in-situ operations. One of the most widely used stabilization methods is lime column technique. Before stabilizing a swelling soil with lime column technique, it is investigated if the lime column works for the soil. This is done by creating a small-scale model of the land in the laboratory. The created models are left for a specific curing time to ensure the stabilization. Determination of the appropriate curing time is important for the performance of lime column. The aim of this study is to determine the curing time for the laboratory models, which are designed for investigating lime column performance, with an easy a n d economic method. The method is based on measuring the ion migration distance by using phenolphthalein which is an acid base indicator. In the scope of the study, a small scale laboratory model was designed for a Na-bentonite clay. The ion migration distance from the lime column in the model was measured by using phenolphthalein in various curing times a n d the measurements were stopped when the ion migration distance reached a constant value. The time in which the ion migration distance started not to change was taken as the cure time. The results obtained in this study showed that phenolphthalein can be a useful tool for determination of curing time in the laboratory applications of lime column.

ABSTRACT: Stabilisation of swelling soils by using lime column technique has been investigated for many years a n d there have been numerous studies on this topic in the literature. The common view in these studies is that stabilisation mechanism of lime column technique is based on physico-chemical reactions occurred as a result of migration of Ca2+ a n d OH- ions from lime column to the surrounding soil. In spite of this, ion migration which is the basis of stabilisation, a n d the factors affecting ion migration have been mentioned in very few studies. This study is a review type study a n d the purpose of the study is to provide a better understanding of the mechanism of ion migration in lime column applications. In the scope of the study, firstly, movement of ions in soil medium in general is explained. Afterwards, ion migration mechanism that occurs during the stabilisation of swelling soils with lime column technique, a n d finally the factors affecting ion migration mechanism are explained by referring to the studies on this topic. In the result of the study, it was seen that in the literature there is no a single a n d precise mechanism that explain ion migration. However, it can be said that the migration of ions in to the soil is a function of ion diffusion a n d mass transport depending on water flow.