Research On Structural Morphosis Design Method Based On The Characteristic Of Trussing Mechanics

Accompanied by rapid economic development,new buildings with abundant performance and strong visual impact are refreshing the name card of the city.Special latticed structure is highly recommended in new buildings due to light weight,reasonable stress and high degree of industrialization.Structural morphology is an interdisciplinary that involves architecture and structure.Moreover,it gives overall consideration to aesthetics and mechanics.From the previous design experience,structural engineers insufficiently participate in initiatory design scheme which restricts rationality in design process.Besides,minor imperfection within initial design stage will show up as a big difference away from reasonable structural style.Hence,deepen research in structural morphology field will provide ideas and instruments for engineers on the stage of primary design and offer effective approach to parametrization design in building.This will significantly improve the participation of structural engineers.The thesis mainly focuses on morphology design in new building.It aims at seeking an optimization method to find the superlative form of the special latticed structure.Under external loads,mechanism system tends to automatically transform into a force-resistant system which mainly contains axial forces.Based on this principle,the thesis puts forward a method in morphology design for special latticed structure.If a structure's shape is the same as a mechanism system in balancing state and the structure undergoes equal or opposite loading cases,then only exist axial forces in the structure.Accordingly in determinate loading case,the structure sharing the same shape with mechanical system which was searched for the lowest systematic potential state is the rational one with optimization.The final result achieves dual objectives that internal force is mainly axial force and that system's potential energy decreases.The change in shape conforms with mechanics logic in the process of optimization.The maximum moment,average moment and strain energy obviously decreases,ultimate capacity of the structure significantly improves,and susceptibility to initial imperfection lowers.The Innovation of method lies in the following items.(1)The method inherits and develops form-finding in flexible structure.The flexible structure experienced form-finding process contains mainly membrane stress,which conforms with the design idea of controlling moment in shell structure.So it is feasible with the help of characteristic in mechanics system to find the coordination between structural shape and stressing state in shell design.(2)The paper enriches chosen space of structure form.By changing the parameters,such as the initial model,the loading case and the constraint conditions,the method will achieve diverse shapes,which will make shape design convenient for the engineers.(3)It realizes numerical simulation of the inverse hanging experiment.Inverse hanging experiment was the important means to carry on research in form-finding in early time.It is vivid and intuitive.Numerical simulation of the whole experiment is able to avoid the precision and time-consuming problem.It tremendously improves efficiency in structure morphology design.Therefore,the method in the thesis is a correct and efficient way to find the coordination between structural shape and stressing state in shell design.It will provide technology support for practical architectural project in primary stage.