Design And Application Of Typical Large-span Structural Morphology Based On Combination Equilibrium Modeling

The history of the development of large-span structures is closely related to the history of human development.With the continuous development of social economy and the continuous improvement of people's living standards,people's demand for various beautiful and diverse buildings is also increasing.However,the traditional form-finding methods such as stress relaxation method and finite element method are more cumbersome to use,and it's difficult to take into account the changes of the "shape" and "force" of the structure at the same time,which is difficult to meet the actual engineering needs.There is a demand for convenient and fast design tools in the conceptual design stage of the structure.In view of the above problems,this paper conducts a detailed study on the composition,principle and application of the parametric form-finding method based on the traditional graphic static method,the Combination Equilibrium Modeling(CEM),and summarizes the design rules based on this method to achieve the form-finding process.Visualization provides a new perspective for designers to conceptually design structures.In view of the above background,this article mainly completed the following aspects:(1)Introduce and analyze the basic mathematical principles,parameter types and morphological design process of the Graphical Static method and its parameterized improvement method-Combination Equilibrium Modeling,summarize and summarize this method in progress The advantages and disadvantages of structural form design,the preparation of pre-and post-processing interfaces based on RHINO and GRASSHOPPER,the realization of form-finding program based on RHINO interface,and through a simple example to show the program's operation process and the changes in structural form after parameter adjustment;(2)The sensitivity of the design results to each parameter when using CEM for morphological design is studied.Different parameters in the topology diagram have different priorities.Its essence is that the number and degree of other parameters are affected when different parameters are adjusted.The greater the impact,the higher the priority.Then,CEM was used to design the morphology of the bridge structure and design engineering examples.The design results were concise and clear,which was consistent with the CEM philosophy.However,at present,it is difficult to use the spatial position of elements or nodes as the design target in the process of structural form design using CEM,and the constraint on the change of structural form is small.The whole may be distorted due to the change in the design value of some units.In view of the advantages and disadvantages of CEM,the idea of improving the design procedure in the next stage is proposed.(3)The design process of the single-layer ribbed spherical reticulated shell structure was systematically studied.The load used in the design considered the structure's dead load and live load.Combined with the stability analysis of the shell structure,the empirical design formula based on CEM is summarized.Secondly,the results of other structural morphological designs based on the single-layer ribbed spherical reticulated shell structure topological diagram are shown.Finally,for the shortcomings of conventional CEM when designing reticulated shell structures,an improved design concept is proposed.