Mechanics Properties Of Rubber Bearings And Earthquake Response Analysis Of Isolated Structure

Seismic isolated structure system is a passive active control system, which is different from traditional anti-seismic structure system. Through setting isolation layer, earthquake energy is absorbed and dissipated and earthquake response of structure is reduced, so that the safe of structure is ensured. Isolated structure system changes the energy dissipation mechanism of traditional anti-seismic structure, i.e. the earthquake energy is absorbed and dissipated by energy dissipative device set in a isolation layer rather than by the structure and structure elements. This excellent energy dissipation characteristic can not be realized by traditional anti-seismic structure. After studying for thirty years, many research results of applied foundation theory and engineering application of isolation technique have been obtained. Up to now, near twenty countries and region in the world have constructed isolated buildings. The strong motion observation records of Northridge earthquake 1994 and Kobe earthquake 1995 have indicated that this isolated structure system is one of the effective and new type structure system for earthquake disaster reduction.Based on the research of many scholars and researchers, this dissertation investigates systematically applied foundation theory and test research related isolation technique, including following aspects: (1) Research on the calculation model and analysis theory of mechanics property of rubber isolating device, such as compression property, tension property, shear property, rotational property and yielding property of isolating bearings, etc. (2) Based on the theory of isolating device, the related test research on natural rubber isolating bearings (RB) and lead-rubber isolating bearings (LRB) has been completed, so as to verify the reliability and calculation precision of proposed calculation model and analysis theory. (3) Simulated earthquake tests of small or large height-width ratio of isolated structure model on a shaking table have been completed, based on the tests, the multi-mass calculating analysis model of the isolated structure system with large height-width ratio has been completed. (4) Proposing the simplified calculation theory of isolated structure system with large height-width ratio and establishing corresponding analysis theory of earthquake response. (5) Researching the practicality of the proposed new calculating model in real isolated structure system with large height-width ratio.Rubber isolating bearing is the key element of isolated structure system .In this dissertation, the research on applied foundation theory of compression, tension, shear, rotation and yielding property of isolating bearing was carried out systematically in the field of linear and nonlinear elasticity. In the research related to compression property theory, a constant related to the vertical stiffness of NRB and LRB has been found respectively, which is defined as compression stiffness factor. The simplified calculation theory of vertical stiffness is established based on stiffness factor. In comparison with otherelastic modulus related to compression, the compression stiffness factor has a significant feature, i.e. it can be obtained directly from test, so that it is a measurable parameter. In addition, in other to estimate systematically the stiffness property of isolating bearing, a series of basic concepts, such as origin compression stiffness, origin longitudinal compression elastic modulus, biasing pressure vertical stiffness, etc. are suggested with corresponding theoretical formula and testing estimation method. Based on the basic concept and calculating theory suggested newly, the deformation calculating theory related to pure compression state and shear- compression state of isolating bearing is established.In the research on applied foundation theory of rubber isolating bearings, the theory related tension property is also established. Based on the compression stiffness factor, concept of tension stiffness factor is proposed and its value is given. The...