Application Of Substructure In Large Chassis Tower Connecting Structure

With the continuous proceeding of urbanization, the structure of complicated high-rise building is becoming an increasingly popular trend in urban architecture, among which the large multi-tower chassis piece of tall building structure attracts much attention due to its diversified forms and various functions. However, the mechanical characteristics of the complex-structured high-rise building and its deformation properties make force analysis and deformation analysis difficult and the accuracy is quite low. The current commonly used research methods include test method and finite element numerical simulation analysis. The test method often takes a lot of time and money and is confined by the complexity of the structure; finite element numerical simulation of the law raises strict requirements for the computer hardware and sometimes, there are some difficulties impossible to solve. Substructure analysis technique is a new method of calculation with quick and efficient analysis. Some of the results have been used in finite element analysis software. For example, the technology sector based on dynamic substructure method is developed in finite element software ANSYS. Substructure technique is mostly used for complex structures which raise high requirements for precision, such as aerospace and mechanical structure of large areas, and it is rarely used in the field of complicated building structures. Therefore, the thesis applies substructure analysis method to the finite element modeling analysis of complex high-rise building structure to improve the accuracy and speed of the analysis of complex high-rise buildings.This thesis sets Siamese twin towers and large chassis structure as calculation model and divides the overall structure into four sub-structures, including the sub-structure portion repeating geometric model of the sub-structure portion and the non-repetitive geometric model. The simple repetitive geometric model structure only forms a substructure when using substructure analysis and undergoes the deviation of models to form other substructures. Therefore, the jointing points between substructures which have the same deviation can be autonomously combined without any special disposal. Therefore, dealing with the jointing between these complex structures needs respective consolidation of the jointing points of substructures. In this way, the sub-structure analysis method in the field of building structureis not confined to repeating geometric model of the structure of the form, which enables us to enter the field of analysis of complex structures. In the analysis of the process of modeling sub-structure, the finite element model of the overall structure should be first set up, then the model will be divided, removed and retained according to specified rules. The pre-set finite element model of the sub-structure is then formed and forms each of the super unit by defining the degree of freedom the way.On the basis of formation of each super unit, substructure analysis goes on, and finally the sub-structure is expanded and the results are extracted. In the analysis of process modeling and analysis of sub-structure, mode of operation are used in the command stream, eventually finishing forming the sub-structure technology template command in circulation, including the generation and use of repetition and non-repetitive geometric model of the sub-structure of the template and static structure force analysis and structural dynamic analysis template. In order to facilitate the accuracy of visual observation sub-structure analysis method, efficient and operability, while using the finite element method analysis model is the same, and the same number, the same form of meshing, in order to ensure that the data in both analysis models under exactly the same premise results of two analysis methods of comparison. The results by two methods are compared as follows:The two analysis methods undergo static analysis and then enter general-purpose processing module to obtain the corresponding displacement contour, the magnitude of the displacement and stress values while recording static analysis and run-time data share memory. Then the modal analysis based on static analysis, analysis methods were used to solve the latter two into the general post processor, to give top twenty natural frequencies and the corresponding mode shapes FIG both Structural analysis method, while the recording mode share data and analysis run time memory. As the results show, in the substructure method for analysis and finite element method to analyze the obtained numerical, results are basically the same. The time taken by substructure analysis is half of that by finite element method and its memory storage is only one third of finite element method.Analyzing efficiency is much higher than the finite element method, at the same time, Since the sub-structure analysis method has a large number of cells forming a small advantage over finite element, which solves many problems which cannot be solved in large and complex structures.