Research On Soil-Steel High-rise Staggered Truss System Interaction

The Steel High-rise Staggered Truss is a new style structure system; its theoretic research and practical application just start. It's found that Soil-Steel High-rise Staggered Truss system Interaction (SSHSTI) research is in blank both at home and abroad. As part of National Natural Science Foundation of China (Grant No. 50078021), the dissertation is focused on the static and dynamic character of the Steel High-rise Staggered Truss, the three dimensions model of SSHSTI with finite element method (FEM) is used to analysis the Steel High-rise Staggered Truss. Some conclusions of SSHSTI and foundation model are derived in the research. The main researches are outlined as the following:1) The three dimensions FEM is used to investigate the displacement and forces of staggered truss with different foundation in elastic ground under horizontal and vertical loads. From the results, the dissertation first point out that the staggered truss system's deformation is mainly effected by the variation of moments and shear forces of columns considering the SSHSTI. Contrast with the results, the dissertation discover that in the three type foundation of strip foundation, raft foundation and pile-raft foundation, the structure system with strip foundation has large deformation and forces variation; the structure system with pile-raft foundation show mini different contrast with the norm calculation.2) The three dimensions FEM is used to investigate the displacement and forces of staggered truss with different foundation in elasto-plastic ground under horizontal and vertical loads. Contrast with the results, the dissertation concludes that the axial loads of column have no essential variation, the variations of moments and shear forces of column are small under horizontalloads in contrast with the structure system in elastic ground, the moments and shear forces variation of column cannot be neglected, and the structure system with different foundation have the close degree variation.3) The single pile horizontal dynamic impedance function in visco-elastic ground considering axial loads is first derived in this field, and the parameter analysis shows that the variation of single pile horizontal dynamic impedance cannot be neglected when considering the axial loads, and it's appropriate to considering the axial loads when calculate the single pile horizontal dynamic impedance.4) The dynamic interaction factors of pile groups under horizontal earthquake actions and dynamic forces considering axial loads are first derived in this field, and the affection degree of the factors by the axial loads are investigated. The Matlab language is used to calculate the pile-group-impedance, and the numerical calculation shows that the axial load only has effect on the numerical of the pile groups' dynamic impedance function, but has not effect on the frequency.5) The method to calculate the natural periods of staggered truss with SSHSTI with raft-pile foundation is decided, and the natural periods of staggered truss with column foot fixed and SSHSTI with raft-pile foundation are calculated and investigated. The natural periods of formal six modes were advanced researched, the floor panel is assumed to be elastic, contrast with the results, first time it's found that the third natural period has a small affection considering SSHSTI. When the axial loads on piles are considered, the other periods in the formal six modes have relative percent variation from 30% to 60%, and the relative percent changes small considering different ground. When the axial loads on piles are not considered, contrast with the considered one, the first and the second natural periods are mainlyeffected, from which conclusions can be drawn that the axial loads affection is obvious to the construction system considering Relaigh damp.6) The dynamic displacement and dynamic forces of SSHSTI with raft-pile foundation under horizontal...