Influence of Local Soil Conditions on the Structural Design and Associated Costs

Abstract

It is known that earthquakes occur along the faults as a result of the tectonic plate movements [1]. The North Anatolian, Northeast Anatolian and East Anatolian Faults create three major fault lines in Turkey. In connection with these fault lines, there are various studies concentrated mostly on the seismicity and the topic of earthquake hazard has been examined by many researchers until today. According to the literature, to cope with earthquake related problems, an utmost attention should be given to the existing building stock and currently available design principles used for earthquake resistant structures in the country. In general, the damage to buildings stem from the lack of knowledge and experience in the field, lack of soil survey database, and structural irregularities in plan and elevation. According to building design codes, the seismic load acting on the structures depends on the seismic zone, the soil type, its period of vibration and the mass of the building [2]. In the present study, the main objective is to evaluate the influence of local site effects on the seismic response of buildings in terms of 2018 Turkish Seismic Design Code provisions and to analyze their impact on the cost of construction of buildings. In the study, a two-story reinforced concrete-framed building (residential house) is used as an example. Using the architectural layout of the building, the thickness of floor slabs and column size are determined. The construction cost is estimated roughly by considering unit costs method. The cost of the reinforced concrete structure is determined by considering 2017 unit price list, specified by the Ministry of Environment and Urbanization [3]. It’s quite clear that the cost of structure built on soil class ZD is more expensive than the cost of the one built on the soil class ZA. The cost difference is around 22,57% between soil classes ZA and ZD.