Determination of shear modulus along with damping ratio values in the field when shear strains exceeds those maximum strains obtained from laboratory tests has a crucial importance in the seismic design of structures whose interaction with soil is more pronounced. In this study, shear modulus of undisturbed samples, obtained from Adapazarı city center during drilling works conducted within the scope of the geotechnical investigation following the 1999 Kocaeli earthquake, were determined. Elasticity of undisturbed Adapazarı samples was measured using a cyclic triaxial test rig. The aim is to obtain relationships between the elasticity moduli from the stress–strain relations of specimens in dynamic and static loading setups, and the axial strains following termination of dynamic tests. Minimum and maximum shear moduli were determined for non-plastic soils and for soils with the plasticity index of PI = 40%. The elasticity modulus ratio (E_N=20/E_N=1) for samples with plasticity index of PI = 40% is higher than those with PI = 20% at the same level of deformation. As the plasticity increases at the same deformation level, both of the E_ds/E_N=1 and E_ds/E_N=1 ratios increase. Moreover, seismic performance of a reinforced concrete frame is evaluated for both fixed and soil-structure system. Seismic demand in soil-structure model with the frame and soil profile considered in this study is observed to be higher as compared to fixed-base frames.

当剪切应变超过从实验室测试获得的最大应变时，在现场确定剪切模量和阻尼比值对于与土壤相互作用更明显的结构的抗震设计至关重要。在这项研究中，确定了在 1999 年科贾埃利地震后岩土工程调查范围内进行钻孔工作期间从 Adapazarı 市中心获得的未受干扰样品的剪切模量。使用循环三轴试验台测量未受干扰的 Adapazarı 样品的弹性。目的是从动态和静态加载设置中试样的应力-应变关系中获得弹性模量与动态测试终止后的轴向应变之间的关系。确定了非塑性土壤和塑性指数为 PI = 40% 的土壤的最小和最大剪切模量。弹性模量比（E_N=20 /E _N=1 ) 对于塑性指数为 PI = 40% 的样品，在相同变形水平下高于 PI = 20% 的样品。随着塑性在相同变形水平下增加，E _ds /E _N=1和 E _ds /E _N=1比率都增加。此外，钢筋混凝土框架的抗震性能被评估为固定和土结构系统。与固定基础框架相比，本研究中考虑的框架和土壤剖面的土壤结构模型中的抗震需求被观察到更高。