Reliability Analysis Of Large-span Reticulated Shell Structure Under The Random Fluctuating Wind Field

With the technological innovation in the field of construction,the large-span reticulated shell structure is widely used in landmark buildings due to its beautiful facade shape.As a structure with small mass and low damping,the large-span reticulated shell structure is naturally wind-sensitive,and is prone to collapse and damage due to the dynamic characteristics of wind disasters.Based on this,it has become an urgent need in the field of civil engineering to analyze the wind resistance of large-span reticulated shell structure in a more refined manner and calculate its reliability under wind disasters.In the past few decades,domestic and foreign scholars have completed a lot of researches on the wind reliability of large-span reticulated shell structures,and formed a clear research ideas,which are mainly divided into three steps:1)Generating random fluctuating wind field;2)Wind-induced responses of reticulated shell structure 3)Quantitative assessment about wind reliability of reticulated shell structures.However,the above research still has certain shortcomings: on the one hand,for reticulated shell structures,the algorithm about generating random fluctuating wind field and Wind-induced responses is not efficient,which poses lots of challenges to the hardware.On the other hand,the randomness of the fluctuating wind field is easily coupled with the nonlinearity of the structure,which increases the difficulty of quantitative assessment of the reliability of the reticulated shell structure.Owing to this,in order to analyze the reliability of Large-span reticulated shell structure in wind disasters more efficiently and accurately,this paper,based on the related achievements of the predecessors,has completed the corresponding improvement.The content is as follows:（1）An optimized method for simulating steady random fluctuating wind field is proposed : based on the classic spectral expression model,a new point-selecting method in high-dimensional random space is introduced.In this way,a random wind field with complete probability information can be constructed with fewer samples.Finally,two engineering examples are selected to verify the efficiency of the method in this paper.The results show that,under the premise of the same number of samples,compared with the classical spectrum expression and dimensionality reduction method,the proposed method in this paper has a significant advantage in the accuracy of the results.（2）Aiming at the large-span spherical reticulated shell structures,an optimized method about wind-induced response analysis is proposed basing on the coupling characteristics of the random wind field and the mechanical property of the reticulated shell structure.Taking the reticulated shell structure with 60-meter span as a numerical example,the rationality of the optimized method is verified.The result shows that compared with the traditional method,the proposed method in this paper can greatly reduce the calculated amount required for wind-induced responses analysis under the premise of meeting the engineering accuracy.（3）Based on the probability density evolution method and the equivalent extreme value distribution,a wind reliability analysis scheme that is generally applicable to large-span reticulated shell structure is proposed.Using this scheme as a quantitative evaluation method for the reliability of the reticulated shell and conducting the parametric study about the reticulated shell structure,the influence of different wind speed conditions and different parameters on the wind reliability of the reticulated shell structure can be obtained,which provides an important reference for the design and construction of the actual structure.