Non-gaussian Stochastic Process Simulation And Its Application In Wind Disaster Vulnerability Analysis Of Transmission Tower Structure

In nature,there are many natural disasters,such as earthquake,typhoon and so on.These disasters seriously threaten the safety of the structure,so in the structural design,we often hope to be able to predict the failure probability of the structure under the disasters of different strength,so as to guide the safety design of the structure.These disasters usually have the characteristics of randomness,such as earthquake,wind,wave and so on.The randomness of the load often makes the behavior of the structure show randomness,which is a random time function.The structure itself also has complex randomness.The randomness of the two interact with each other,which will make the structure show more complex behavior.Therefore,it is necessary to study the behavior of the structure under random vibration People pay more and more attention to the damage problem.Generally speaking,the randomness of structure can be expressed by random variables,and the randomness of load is often treated as a random process.In practice,the random load often presents a certain non-Gaussian characteristic,which will make the behavior of the structure more complex.Based on this,it is necessary to study the influence of non-Gaussian random load on the vulnerability of the structure.Therefore,aiming at this research content,this paper first studies the stationary non-Gaussian stochastic process,trying to find a more applicable and efficient simulation method.In addition,considering the non-Gaussian load,the vulnerability analysis of the structure is carried out to analyze the impact of the non-Gaussian load on the vulnerability of the structure.Combined with the existing vulnerability analysis methods,the vulnerability analysis method under non-Gaussian excitation is developed.Finally,it is extended to the vulnerability study of transmission tower line system under non-Gaussian wind load.The main contents of the text include:(1)Research on simulation method of non-Gaussian stochastic process.In order to find a more applicable and efficient simulation method for non-Gaussian stochastic process,a numerical method based on Mehler formula is used to solve the equivalent correlation coefficient.Combined with spline interpolation theory,an efficient method for solving the equivalent correlation coefficient is developed.Based on the FMKL generalized lambda distribution,a new transformation relation for the simulation of nonGaussian stochastic process is established.The transformation relation has a wide range of applications,a single system and strong applicability.Combining these two methods,an efficient and accurate non-Gaussian stochastic simulation method is proposed,which is extended to multi variable non-Gaussian stochastic process simulation.(2)Structural vulnerability analysis under non-Gaussian excitation.Based on the existing vulnerability analysis methods and the stochastic process simulation method proposed in this paper,a vulnerability analysis method under non-Gaussian excitation is developed.Taking a simple steel frame as an example,the influence of structural randomness and different non-Gaussian characteristics on structural vulnerability is analyzed.It is necessary to consider the non-Gaussian characteristics of the load in the structural vulnerability analysis.(3)Random wind-induced vibration response and vulnerability analysis of UHV transmission tower under non-Gaussian wind load.Aiming at a real transmission tower line system,a finite element model is established to analyze its random wind-induced vibration response under non-Gaussian wind load.Taking the displacement of tower tip as the performance index,the performance-based linear fitting method is used to analyze its vulnerability,which provides a new idea for the vulnerability research of transmission tower line system.