In this research presented modelling, computing and application particularities of the structural aseismic control device which response redaction effect an average 61-79% relatively to conventional structure under earthquake excitation. For modelling mention device reinforce solid, structural solid, spring and contact finite elements was used. For contact element accepted conventional Coulomb frictional model. Governing non linier equation of motion is modelled as multidegree of freedom system with discontinuous and continuous models and solved adopting direct integration algorithm with coupling of the control system and system identification toolboxes. One of the very important earthquake action phenomenon-restoring force mechanism was found out, proved and it was used for modelling a novel no restoring mechanism aseismic passive control device. Investigated control device may be economically in the simple or small scale structures because have no any restoring mechanism.

Presented Structural Seismic Isolation Method (SSIM) aims to provide high safety for Highly Reliable Structures (HRS) against strong earthquakes including near-fault and long-period ground motions. The examined structure is converted to Structural Seismic Isolation System (SSIS) by the SSIM method which exhibited inverse pendulum behaviour. For this purpose, structure foot base and foundation contact surfaces have been designed as any curved surfaces (spherical, elliptical, etc.) depending on the earthquake-soil-superstructure parameters and this contact surfaces have been separated by elastomeric (lead core rubber or laminated rubber bearings) seismic isolation devices. It would allow the structure foot base to turn around gyration centre through rubber bearing contact and maintains similar behaviour to the super-structure. SSIS system provides the possibility of keeping the natural-period of the structure in a larger interval, which is greater than the predominant-period of the majority of possible earthquakes (including near-fault pulse) using currently existing conventional elastomeric isolators with up to 4 second period. Thus, the structure can sustain its serviceability after strong and long-period earthquakes. In this study SSIS system’s performance is presented for high-rise building structures, for this aim, the finite element model of the building (Bg) structure with SSIS system (SSIS-Bg) has been prepared and the nonlinear dynamic analysis of the model has been conducted using strong and long-period ground motions. Results indicate that the base and top accelerations, base shear and base moment responses of the SSIS-Bg structure is 23.21 %, 75.47 % and 85.74 % in average lower than the Conventional Application Method of Seismic Base Isolation Devices for Building (CAMSBID-Bg) structures respectively and it is not prone to resonant vibrations under long-period earthquakes related with the excessive deformation in the isolation layers in case of using CAMSBID-Bg structures. It should be noted that in this study with the presented SSIM method and SSIS system, it is aimed to protect only the Highly Reliable Structures(HRS) from the effects of strong and long-period ground motions and these structures (HRS) are classified as follows: 1) Nuclear Containment Structures; 2) High-rise buildings that contain information, operating systems, sensitive instruments, communication systems, routing systems, bank operating systems, databases, management systems and other similar facilities that are linked to the security and economy of a country; 3) High-rise hospitals etc.

The new Structural Seismic Isolation System (SSIS) intends to provide high safety for important structures such as nuclear power plants, offshore oil platforms, and high-rise buildings against near-fault and long-period earthquakes. The presented SSIS structure foot base and foundation contact surfaces have been designed as any curved surfaces (spherical, elliptical, etc.) depending on the earthquake-soil-superstructure parameters, and these contact surfaces have been separated by using elastomeric (lead core rubber or laminated rubber bearings with up to 4-second period) seismic isolation devices. It would allow providing inverse pendulum behavior to the structure. As a result of this behavior, the natural period of the structure will possess greater intervals which are larger than the predominant period of the majority of the possible earthquakes including near-fault zones. Consequently, the structure can maintain its serviceability after the occurrence of strong and long-period earthquakes. This study has investigated the performance of the SSIS for the nuclear containment (SSIS-NC) structure. The finite element model of SISS-NC structure has been developed, and nonlinear dynamic analysis of the model has been conducted under the strong and long-period ground motions. The results have been presented in comparison with the conventional application method of the seismic base isolation devices for nuclear containment (CAMSBID-NC) and fixed base nuclear containment (FB-NC) structures. The base and top accelerations, effective stress, and critical shear stress responses of the SSIS-NC structure are 48.67%, 36.70%, and 32.60% on average lower than those of CAMSBID-NC structure, respectively. The result also confirms that the SSIS-NC structure did not cause resonant vibrations under long-period earthquakes. On the other hand, there is excessive deformation in the isolation layers of CAMSBID-NC structure.

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In this study, the possibility to use Horasan mortar as a sliding interface material for pure friction aseismic isolation system is investigated. Both experimental and numerical studies are conducted to examine the effectiveness of using this material in structural isolation systems of buildings with no overturning moment, as it has shown some attractive experiences in time based on the existing related literature. Responses of four storey lightweight building are numerically investigated by finite element modelling in MATLAB; whereas the University Consortium on Instructional Shake Table (UCIST) is used to study the responses of the same building during experimental works. Comparison of both studies is shown to be in a good agreement in terms of resulting structural response accelerations, velocity and displacements. Approximately 28 - 31 % reduction of base floor acceleration is achieved; and the maximum sliding velocity and displacement are found to lie between 0.33-0.45 m/sec and 0.0353-0.0559 m respectively; which fall within the recommended standards’ limits. As a result, these findings demonstrate the effectiveness of using Horasan mortar as friction interface material which has additionally gained experience in more than ten centuries.