Doctor of Philosophy

thesisOgden Valley, in Weber County, is a fault trough or graben. It is known as one of the "back valleys" of the Wasatch Range. Consolidated rocks of pre-Tertiary age, unconsolidated and poorly consolidated rocks of Tertiary age, and unconsolidated rocks of Quaternary age constitute the rocks of Ogden Valley and its watershed. The pre-Tertiary rocks are exposed in the mountains surrounding the valley. These rocks range in age from Precambrian to late Paleozoic. Several stratigraphic gaps exclude the rocks of Ordovician, Silurian, much of the Devonian, and the Permian systems from the area. The pre- Tertiary rocks are not very significant as water bearers in the area. The Tertiary rocks include Knight Formation, Norwood Tuff, and upper Pliocene (?) Fanglomerate and range in age from early (?) Eocene to late Pliocene(?). Miocene rocks are missing. The Knight Formation sup¬ plies about 860 acre-feet of water annually to Bennett Spring. The Norwood Tuff has a low permeability and acts as an underlying confining bed in Ogden Valley. The upper Pliocene (?) Fanglomerate is unconsolidated and unsorted. The formation has a relatively low permeability; therefore, it will not receive much recharge from precipitation. The Quaternary rocks include more than 400 feet of unconsolidated sediments of the Pleistocene and Recent epochs deposited within the graben. The Pleistocene sediments consist of pre-Lake Bonneville and Lake Bonneville gravels, sands, silts, and clays. The Recent deposits are fan gravels, flood-plain gravel, sand, and silt, landslide deposits, and slope wash deposits. Pre-Lake Bonneville deposits include fan gravels and stream-laid deposits of gravel, sand, silt, and clay; they make up the artesian aquifer, whose waters are confined by the over¬ lying silt and clay of the Alpine Formation of Lake Bonneville age and by the relatively impermeable underlying Norwood Tuff. Overlying the Alpine Formation are the sands and gravels of the Bonneville Formation which, together with Recent sands and gravels, contain perched water bodies. In the recharge area these Bonneville and Recent deposits are hydraulically connected with the artesian and water-table aquifer. Ogden Valley is drained by three forks of Ogden River, and the flow of this river is regulated by the earth-fill dam which impounds the water of Pineview Reservoir. Recharge to the ground-water reservoirs is by seepage from waterways and irrigated lands, and infiltration of precipitation. The estimated minimum recharge in 1970 was 34,300 acre-feet. The greatest contribution to this recharge is from seepage waters from the waterways and irrigated land. Discharge from the ground-water reservoirs is by (1) wells, (2) evapotranspiration,and (3) springs. The estimated minimum discharge in 1970 was 34,000 acre-feet, of which 20,000 acre-feet was discharged by evapotranspiration. The most important causes of water-level fluctuations in the artesian wells are discharge from the wells and loading by Pineview Reservoir. Since November 1936, Pineview Reservoir has created a unique situation in Ogden Valley by adding a load on the underlying artesian aquifer. Thus, with an increase in the storage of the surface reservoir, the artesian aquifer is compressed and the water levels in the wells start to rise. An increase of about 4,800 acre-feet in the storage of Pineview Reservoir corresponds to a rise of water level in the test well, (A-6-2) 18 bab-1, of one foot. The chemical quality of the ground water in Ogden Valley is good and the water is suitable for household and irrigation purposes. The results of bacteriological analyses of water samples from ten wells indicate that the water in six wells is satisfactory, but the water in four wells around Eden may be classed as unsatisfactory for drinking purposes. The artesian aquifer in Ogden Valley probably could be developed further if the present users would be willing to accept a reduction in pres¬ sure in exchange for the additional water. The water-table aquifer probably could be developed to yield five times its present yield of 100 acre-feet per year

D750 karayolu Kızılcahamam-Gerede arasındaki yol yarmalarında şev duraysızlıklarına yönelik tehlike sınıflandırma sistemi uygulaması

TÜBİTAK ÇAYDAG01.12.200

Usedanje šibko cementiranega tufa

Weakly cemented tufas are sand and silt size soils that are weakly bonded with thin films of carbonate cement. The void ratio is rather high and equal to approximately 1.2. Collapse occurs as a result of the destruction of the weak bonds upon loading and/or wetting. The index properties and the collapse potential (Cp) of tufa were determined in the laboratory. In the determination of the collapse-potential values the single-ring oedometer method was considered to be a suitable and simpler tool. In plotting the oedometer test results the use of a natural scale was preferred over a logarithmic scale so that the void ratio-pressure relationship is polynomial. Under loading the soil settles with the natural water contenthowever, saturation increases the collapse that is initially triggered by the pressure increase. The pressure level is a significant parameter in the magnitude of the collapse and therefore in the total settlement. The settlement of foundations due to a collapse of the soil structure can be estimated directly using the oedometer test results and empirically using the index properties, like the initial void ratio (e0), the difference in the fine content between the dry and the wet sieve analyses (PFAW) and the natural unit weight. A comparison of the direct and empirical approaches yielded a good agreement.Šibko cementiran tuf je zemljina z velikostjo zrn peska in melja, ki so šibko povezana s tankimi plastmi karbonatnega cementa. Količnik por je dokaj velik, okoli 1,2. Zrušitev teh zemljin se pojavi kot rezultat popuščanja rahlih vezi zaradi obtežitve ali namočenosti. Njihove indeksne lastnosti in zrušitveni potencial smo določili v laboratoriju. Pri določanju vrednosti zrušitvenega potenciala smo uporabili edometrsko metodo, s tem da smo pri risanju rezultatov testov privzeli naravno skalo in ne logaritemske, tako da je razmerje med količnikom por in tlakom polinomsko. Pri obremenitvi se naravno vlažna zemljina posede, poveča se zasičenost in s tem obseg zrušitve. Pritisk je pomemben parameter pri obsegu zrušitve in s tem tudi pri celotnem posedku. Posedanje temeljev zaradi zrušenja zemljinske strukture lahko neposredno ocenimo iz rezultatov edometrskih testov in empirično z uporabo indeksnih lastnosti kot so začetni količnik por, razlika v fini sestavi med suho in mokro sejalno metodo in prostorninska teža. Primerjava med direktnimi in empiričnimi pristopi je pokazala precejšnje ujemanje

Characterization of the Antalya (Turkey) tufa deposits

Carbonate rocks in Antalya (Turkey) which have previously been called travertine should, because of their biogenic origin and deposition in a cool-water regime, be termed tufa. Tufas in Antalya are the products of physico-chemical and biogenic precipitation. In the biogenic process, precipitation was caused by decreasing partial pressure of CO, via photosynthesis of algae or bacteria. Following precipitation, the tufas under-went meteoric-vadose cementation and diagenesis. the Antalya tufa basin consists of horizontally-bedded carbonate sediments which are end products of a lacustrine depositional environment. However, a perched springline system has played an important role, serving as a starting point for calcium-carbonate precipitation. The morphology of tufa coastal cliffs is controlled by sea erosion. Thus, terraced morphology, except for small areas (e.g., Masadagi), should be considered a result of erosion. In this study, tufa deposits of Antalya were characterized with respect to mineralogy, sedimentology and surface morphology. In addition, for the future multidisciplinary needs (engineering and environmental) other aspects on tufa formation are discussed

3-DIMENSIONAL NUMERICAL MODELING OF TUNNEL INDUCED DEFORMATION FIELD (NECATIBEY SUBWAY STATION, ANKARA, TURKEY)

In heavily settled areas, deformations induced by the tunnel excavation may cause serious damage to nearby structures. Therefore, it is necessary to study effective means of controlling tunnel induced deformations. The main parameters affecting the failure and deformation state of the soil around a circular underground opening are the physical characteristics of the soil, the diameter of the opening, and the support pressure. In this study, 3-Dimensional (3D) FDM analyses were conducted to assess tunneling induced deformations, along with movements around Necatibey Station of Kizilay-Cayyolu metro line (Ankara, Turkey). During sequential excavations, temporary and permanent shotcrete lining was also simulated. The soil behavior is assumed to be governed by an elastic-perfectly plastic constitutive relation based on the Mohr Coulomb criterion. The computed deformations around these openings have been compared with the in-situ measurements. The results of the study revealed that the 3-D elasto-plastic analyses yield comparably good correlation with the in-situ measurements

Integration of electrical resistivity imaging (ERI) and ground-penetrating radar (GPR) methods to identify soil profile around Necatibey Subway Station, Ankara, Turkey

Electrical Resistivity Imaging (ERI) and Ground-Penetrating Radar (GPR) methods were utilized in this study to identify soil profiles around Necatibey Subway Station of Kizilay-C, ayyolu metro line, Ankara, Turkey. The Necatibey Metro Station is located within the alluvial deposits of Dikmen stream and the so-called Ankara clay. At the metro station, a number of boreholes were drilled. However, due to the spacing of the boreholes the boundary between alluvium and Ankara clay deposits could not be separated precisely. Thus, in this study, ERI and GPR methods were utilized to distinguish soil types at the study area. GPR measurements were taken from a total of 14 profiles and total length of the profiles was about 320 m. For every ERI measurement section, Schlumberger Dipole-Dipole, Dipole-Dipole, Schlumberger and Wenner arrays were used. Results from the geophysical measurements identified that the fill materials are underlain by the Dikmen stream channel deposits, which consist of silty clay and gravelly sand units. The study also shows that the Dikmen stream channel deposits are underlain by the Ankara clay unit. The meaningful range of resistivity values was between 1 and 15 Omega m, and the GPR signals were strong in sandy units while they attenuated in clayey environments. Based on borehole logs, ERI and GPR data, three-dimensional lithological subsurface model of the survey area was constructed. The resultant three-dimensional diagrams may serve engineers as a practical tool during different construction stages, groundwater-surface water interactions within short and long term, and probable remedial measures