The overall objective of this dissertation is to develop new computational algorithms for application to real-time hybrid simulation (RTHS) of complex structural systems subjected to multi-natural hazards. Resiliency of structural systems under natural hazards is of interest. Real-Time Hybrid Simulation (RTHS) is a testing tool that can be used to assess the resiliency of such systems. In a RTHS the complete system is considered, where selected components for which computational models exist are modeled numerical and the remaining components are modeled physically in the laboratory. The former is referred to as the analytical substructure while the latter the experimental substructure. It is necessary to expand RTHS to accommodate large complex structural systems that reflect real world problems. The current state-of-theart includes modeling systems as two-dimensional planar problems with a limited number of degrees of freedom that excludes soil-foundation-structural system interaction effects. It is necessary to expand RTHS to three dimensional structural systems, to include soil-foundation-structural system interaction effects, to develop computationally efficient algorithms to enable the real-time numerical integration of the equations of motion of a system with a large number of degrees of freedom, and to deal with systems that possess many response modification devices (eg, nonlinear viscous dampers) while only a limited number of experimental testbeds are available for a RTHS. Expanding RTHS to investigate the resiliency of large and complex renewable energy generation structures, such as offshore wind turbines, is also investigated and RTHS is proven to be a viable tool to understand the long-and shortterm behavior of their piled foundation.