Analysis And Software Development Of Complex Isolated Buildings

In the developed isolation approach and the buildings functional requirement, the isolated buildings become complex in the structural type, such as the irregularity superstructure, the multi-tower base isolated structure with large bottom, long span building, isolators mounted on independent columns and so on. As to these complex isolated buildings, current references and studies don't account explicitly in response of structure and the influences of isolated buildings on cushioning effects. What's more, there have no concrete regulations concerning complex isolated buildings in prevailing codes, It is only suggested that the rules of irregularity fixed based buildings are referred to. Therefore, this paper makes a detailed and systematic discussion on some kind of complex isolated buildings and mainly focuses on the following things:(1) To estimate the performance of vertical irregularity of isolated buildings, the vertical mass irregularity and vertical stiffness irregularity of isolated buildings are considered. A vertical irregular isolated building is derived for MDOF system, and the elastic and the elasto-plastic time history methods are used to analyze two actual multi-stories isolated buildings. Distributions of shear force and variability coefficients of shear force are discussed due to various mass and stiffness, Weak layers are indicated as to the vertical irregular isolated buildings. Some advices are presented in this paper for designing the vertical irregular isolated buildings.(2) The rigid layers in series models is obtained as the torsional irregular isolated buildings and the torsional response of the torsional irregular isolated building is investigated, there are bidirectional lateral displacement and a torsional angle in a floor. With the objective of studying the influence of:the stiffness eccentricity in the superstructure; eccentricity in the isolation system; the stiffness of the isolation system. Results are presented in torsional amplification of isolation. Proposed guideline define that a base-isolated building has torsional irregularity.(3) The special type isolated building defined as multi-tower with large bottom is discussed in this paper. The rigid layers in series/parallels models are obtained and the elastic time history method is used to analyze the performance and response of structure. Model analysis is applied to symmetric multi-tower with large bottom isolated building. The results reveal that the symmetric multi-tower isolated building with large bottom can be a simplified general isolated building. With the objective of studying the influence of the mass eccentricity in the towers and the asymmetric towers, coefficients of shear force, the ratios of period and the ratios of drift are discussed. An actual multi-tower isolated building with large bottom is used to compare the response in the vertical earthquake, bidirectional lateral earthquake with tri-directional earthquake, the effects of bottom height, the mass eccentricity in the towers and the asymmetric towers are investigated. It is concluded from the study that the multi-tower base isolated building with large floor should be symmetric and central in order to increase performance of isolation.(4) When isolators are mounted on independent columns, large displacement of the isolator in the earthquake results to P-Δeffects. The special type isolated building is defined as isolator mounted on independent column isolated building. This special type isolated building is possible to be development of overall or local structural instability under earthquake due to P-Δeffects. This paper deals with the local isolators mounted on independent column static stability equilibrium equation, the failure criteria of local structures and the ultimate lateral force is revealed. What's more, the overall structural dynamic stability is investigated. An actual special isolated building is carried out to discuss the dynamic failure of structure with the effect of earthquake, vertical force and stiffness of independent column.(5) The deformation of isolators of an actual long span isolated building is tested due to temperature variation and concrete contraction, the results reveal that the end isolators deformation has exceeded the tolerance deviation. Therefore, the reinforced concrete frame isolated building is analyzed the response under temperature variation and concrete contraction, the rules about deformation and force of isolators and superstructures are obtained. According to buildings thermal design region, the distance of expansion joint of isolated building are proposed in different regions. Meanwhile, the distance of construction joint are defined due to heating design of building. (6) The observation and the life cost analysis are described the seismic performance of complex isolated buildings. Several actual isolated buildings are investigated after Wenchuang earthquake, the cracks and destructions of buildings are observed. The cost-effective seismic performance criteria are proposed. The costs of construction, failure consequences, including death and injuries, as well as discounting cost over time, are considered. The selection of building function and buildings life are evaluated to influent life cost of the complex isolated buildings.(7) This paper use Matlab and Java to accomplish the complex isolated buildings analysis software. According to Chinese seismic design code, the software can be employed to calculate the dynamic response, stability analysis and life cost anlysis.