CONSIDERATION OF SOIL-STRUCTURE INTERACTION IN SEISMIC ANALYZING OF STEEL STRUCTURES BY USING OF HYBRID DAMPER –ACTUATOR BRACING CONTROL (HDABC) YSTEM

The traditional dynamic analysis of the structures has accomplished on the fixed-base models. In general, the response of structures subjected to earthquake excitations are involved by three main components: structure, foundation, and the soil site layers. Seismic analysis of structural systems with the fixed-base model is suitable for structures built on the bedrock. If the structure has constructed on soft soil, both the control algorithm and the structural system shall include the Soil-Structure Interaction (SSI) thatcovers the flexibility of the soil and the displacement of the foundation. This leads to an increase in the number of the system’s degrees of freedom that is changes the structural response behavior and accordingly control actions. This paper used a new type of hybrid control, combining passive and active systems, the Hybrid Damper-Actuator Bracing Control (HDABC), that is an effective protection system. In the structures which used the closed-loop control system whose utilities by Linear Quadratic Regulator (LQR) techniques to identify the structure with hybrid control. In this study, the effects of SSI on the seismic response of the steel structures under strong earthquakes who has built on shallow foundation and supplied with HDABC system, as energy absorber elements has been investigated. For this purpose, the moment resistant steel frames are considered and the time history analysis of them has treated on the structural models with either considering the SSI or without. The smart structure modeling and control design is carried out using MATLAB software in the state space form. The substructuring method achieved from SSI software such as SASSI2000 has used to evaluate the SSI dynamic response. Based on the analysis response, they are shown in the SSI cases, control forces result are more reduced of the structural response than without SSI. The control forces sequence in without SSI are smaller than with SSI case and SSI is effective for the hybrid control, needs to be included in the design of hybrid system as well as other types of the control for buildings on soft soil.

Keywords:

Hybrid Control System , Soil-Structure Interaction , State-Space Model , LQR