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Pushover and nonlinear dynamic analysis method are applied to analyze the seismic performance of RC frame structure with or without slabs under the action of multiple factors in this thesis. Meanwhile, the structural response exerted by oblique seismic action is summarized from the theoretical formula derivation. By analyzing and comparing two kinds of established models, the results demonstrate that with various axial compression ratio and moment magnifying factors of columns, the seismic performance of the structure will be degraded when the influence of the floor is taken into account. And the increment of the values of axial compression ratio μ and moment magnifying factor of column η c with the floor exceeds that without the floor. Moreover, Earthquakes input along the principal axis can realize the “strong column weak beam” of the structure. Considering the influence of floor, when the value of axial compression ratio is higher than 0.56 or moment magnifying factors with the floor increases above 2.0, frame structure under oblique seismic action can form “strong column weak beam” yield mechanism.

In reinforced concrete (RC) column footings, the soil stiffness can significantly affects the punching shear strength of the foundation slab. The present study conducted eccentric compression tests on three RC column footings considering the complex interaction between the soil and structure, and investigated the load-carrying capacity, displacement distribution, reaction distribution, failure mode, crack development, and strain distribution. The test parameter was flexural reinforcement ratio in the foundation slab. The test results showed that the footing specimen with lower reinforcement ratio was susceptible to brittle punching shear failure, and the flexural reinforcement ratio affected the crack distribution and the spalling of concrete cover. Since only one specimen was used in each flexural reinforcement ratio, however, the test results should be carefully considered. On the basis of the test results including existing studies, the effect of design parameters on the punching shear strength was evaluated. As a result, a new method was developed to predict the punching shear strength by addressing the eccentric compression force.