Assessment of Dynamic Effects of Soils With In-Situ Tests and Numerical Methods On Adapazarı-Karasu State Road

Abstract

Earthquakes are natural events that cannot be prevented. However, with the measures taken, the loss of life and property in earthquakes can be reduced. To take this importance, it is necessary to understand the relationship of the earthquake with both the ground and the structure. Considering the ground relations of the earthquake, liquefaction and related settlement and lateral deformations have an important place. Türkiye is located in fault zones that can cause major earthquakes and is in a problematic area as a result. For this reason, it is necessary to carefully examine the behavior of the ground during an earthquake. Sakarya province, which is close to the North Anatolian Fault Zone route, is located on the Sinanoğlu-Limandere route of Adapazarı-Karasu State Road. This area is one of the most dangerous areas in terms of earthquakes. 1999 Kocaeli and Düzce Earthquakes confirm this situation. The entire study area consists of gravel, sand, and clay deposits in flat areas that have been developed in older depressions in stream beds located in the flooded alluvial plain of the Sakarya River. It consists of floodplain sediments that have not undergone little or no consolidation. In general, these units containing silt, clay, and sandy character are also rich in organic matter content. The plain elevation is very close to the water level of the Sakarya River and it is seen that the groundwater level is at the surface for a significant part of the year. In cities such as Sakarya that contain alluvium and have high precipitation, the probability of ground damage due to earthquakes is high. The liquefaction potential of the soil can be examined by in situ geotechnical experiments and laboratory experiments in the field. Since it is difficult to take undisturbed samples for cohesionless soils in the field, field tests are used extensively in the literature to determine liquefaction potentials. Over the years, many studies and related case studies have been conducted to determine the liquefaction potential of SPT and CPT. In the thesis, the soils that are thought to have liquefaction potential and which are located at the Adapazarı-Karasu State Road Sinanoğlu-Limandere transition in Sakarya province will be investigated. Alternatives have been considered instead of the road crossing to prevent the settlements that will occur and will occur at the road crossing. The bridge alternative, which is seen as the most economical solution, has been studied. While studying the bridge alternative, earthquake records specific to the region were selected. One-dimensional free-field analyses were carried out. The related bridge alternative has been modeled in three dimensions with the finite element program. By using the obtained free field displacements, the effect on bridge piles under dynamic displacements has been investigated. The analytical and numerical analysis results were then compared and suitable remedial measures have been proposed.