# title
Hacheem, Zuhair Abd (2020-07). ADAPTIVE CONTROL FOR SMART SOIL-STRUCTURE INTERACTION SYSTEMS WITH SEMI-ACTIVE DEVICES. Doctoral Dissertation.

# abstract
Supplemental structural control has become a focus for researchers to improve structural performance and to maintain structural safety during hazardous events and corresponding loads. For structures without supplemental control systems, the dynamic interaction between the structure and the soil can have significant impact on the structure response, and the impact increases when structures are constructed on soft soil. Existing research has not deeply investigated soil-structure interaction effects in structures with smart control systems. The object of this research was to study the theory of the simple adaptive control (SAC) algorithm and magnetorheological (MR) damper to reduce the response for soil-structure interaction in performance-based building control design with hazard loads. Three main issues were investigated to accomplish this goal. First, many simplifications and hypotheses were utilized throughout this work to obtain the investigation computationally comprehensibly. Model reduction techniques were adopted to estimate the equivalent stiffness matrices for structures and foundations. For structures, the equivalent stiffness matrices for frame and frame shear wall systems were developed in the finite element software ETABS, as they relate to three-dimensional structures and their geometric and material properties. For soil, the equivalent stiffness matrices for rigid foundations with different soil profiles were determined using the finite element software ABAQUS. Next, the effect of SSI is numerically investigated for the variation of the period of structures (T), the structure's slenderness ratio (?), the structure-to-soil stiffness ratio (?), and set of earthquake loads. The mathematical model of the one-story building (SDOF) is used to explore the general structure behavior under consideration. The results reveal that the SAC algorithm is capable to mitigate the responses of fixed base structures and SSI. Moreover, the responses and control forces of SSI systems increase with the increase in the slenderness ratio (?). The SSI systems need to more cost of control effort and the control forces increase with increasing of the period of the fixed support structure (T). Finally, the SAC algorithm was found to be highly effective at maintaining structures experiencing SSI effects in the presence of variations in the structural systems (i.e., frame and frame shear wall systems) and soil stiffness. The performance of controlled structure changes when the soil stiffness varies from soft to medium, decreasing with decreases in soil stiffness. The performance also decreases as the stiffness of the structure increases (i.e., the performance of a controlled frame shear wall structural system is less than that of a controlled frame system). The SSI effect is very clear in structures constructed on soft soil, stiff structures, and frame shear wall systems.

# websites[].label
ADAPTIVE CONTROL FOR SMART SOIL-STRUCTURE INTERACTION SYSTEMS WITH SEMI-ACTIVE DEVICES