Doctrines of earthquakes and also the latest approaches of earthquake resistant building design in standards need to be revised periodically. While the revisions and updates in the American standards occur over periods of three or five years including limited subjects, in Turkey the same revisions are done once over long periods including the whole subjects of the standards. As examples the standards of 1975, 1998, 2007 and finally 2018 could be given. Especially, in 2018 standard (TBEC-2018) many changes were made over concepts and criteria. The procedure of calculating the earthquake loads in 2018 standards is similar to the one in the American standards of (ASCE-7-16), however for the element design the changes are shown as developments over the one of 2007 earthquake standard (TEC-2007). The changes made by 2018 standard for calculations of earthquake loads and their effects on civil engineering are very important factors of new building design. The earthquake load affecting a building which is the first factor of earthquake resistant building design shows important differences according to the condition changes in the standard. Based on this motivation in this study reinforced concrete frame type buildings of different elevations were researched by using ETABS (structural software for building analysis and design) according to linear equivalent seismic load method. According to the analysis results of the chosen buildings, a comparison forthe base shear force, top displacement and relative story displacement between TEC-2007, TBEC-2018 and ASCE 7-16 standards was carried out. From the analysis results, it is found that for most of the soil classes while the maximum base shear forces in 3 and 5-story buildings are achievedat TEC-2007, the maximum base shear forces in 7 and 9-story buildings are achieved at TBEC-2018. Also, it is predicted that the higher increment in the design forces of buildings with higher elevations is obtained at TBEC-2018 for strong soils, and at TEC-2007 for weak soils. By considering cracked sections at TBEC-2018 the calculations displacement and period was affected as periods in TBEC-2018 were increased by almost 34% respected to TEC-2007. The same increment ratio was determined for ASCE 7-16 as 45%. Also, as a response for the increments in period, the spectral acceleration determined from the elastic spectrum diagram was decreased. At the end of the study, nonlinear performance analysis was also performed and performance points were determined according to the demand spectra of the seismic codes. ASCE's demand displacement values are in any case lower than Turkish codes. TBEC-2018 reveals less displacement demands in high-rise buildings than TEC-2007. The closest results for the three regulations occurred on the softest grounds.According to the results obtained from the static pushover analysis, a ductile behavior occurred in all of the structural systems and plastic hinge mechanism started from the beams firstly.

In the present research, the optimum condition of the grout consisting of cement, fly ash, superplasticizer, and water was determined to produce the most durable and impermeable deep mixing columns (DMC) on silty soils. It is aimed to reduce the grout cost and environmental pollution by using high-rate fly ash in the grout. Superplasticizer additive was used to increase the flow consistency of grout consisting of high-rate fly ash. The design of the experiments was made using the 5-parameter and 4-level L16 orthogonal array table specific to the Taguchi method. Accordingly, the unconfined compression strength (qu) and the permeability coefficient (k) of the soil-binder mixtures at the end of the 7-and 28-days curing time were determined. According to the test results, regression analyzes were performed and models with high reliability were created for qu and k. As a result of optimization studies, to produce DMC having high strength and low permeability, grout content should be consisting of 14% cement, 14% fly ash (ratio of fly ash in the binder is 50%), 2.68% super plasticizer additive, and 0.95 water/binder ratio. The pozzolanic reactions in soil-binder samples with different grout contents were examined by SEM analysis.