Analysis Of Construction Process Of Space Tubular Truss Structure And Health Monitoring Assessment

With the development of social economy and the progress of science and technology,the construction of long-span spatial structure has become a symbol of a country's scientific strength.Due to the flexibility and diversity of the structure,it is widely used in various kinds of large venues and other iconic building structures.The safety risk of space structure exists in the whole life cycle and the construction technology of long-span space structure is complex and complicated,the construction stage is the key to determine the life of the structure,and the probability of its occurrence risk is much higher than other periods.Therefore,the health monitoring in the construction stage is of great significance to the life and operation of the structure.Because of the diversity of spatial structures,the different construction techniques and the complex relationship between forces,the monitoring of different spatial structures needs a matching acquisition and evaluation system.At the same time,there are different opinions on the health evaluation method of spatial steel structure.In view of the above problems,this study took the space pipe truss structure of Tianshui Stadium roof as the background,simulated and analyzed the construction schemes in each construction stage,selected the optimal construction method and carried out realtime monitoring of its key members on site.Finally,the naive Bayes classifier and Bayes network were used to effectively output the discriminant probability of the collected data,and the following results are obtained after analysis:Through the simulation and measurement of the instantaneous lifting process and the high-altitude splicing process of the tubular truss structure,the particularity of the tubular truss structure was obtained.The naive Bayesian classifier was established by using a large number of data sources and its data processing analysis showed that the mechanical changes of each member of the spatial pipe truss structure of Tianshui Stadium were within the safe range during the hoisting construction stage.The load shedding process of the stadium roof was simulated under different schemes by using the finite element analysis method,which was dominated by the bearing displacement method and supplemented by the life and death element method.The measured data collected in the construction process were substituted into the previously established Bayesian classifier for training,and the pre-warning values required by the posterior probability of stress change of each member during construction unloading were solved to ensure the safety of unloading construction.Using the a posteriori probability of prior probability of correction,solving the key link in construction process of the maximum stress changes the impact factor of the whole structure.According to the definition of advantage in probability statistics,the safety evaluation of the whole process of stadium construction was carried out.At the same time,based on the safety assessment of important members in the building reliability standard and the data analysis collected in the field,it was concluded that the safety level of key members in the construction stage was all level A.Based on the above theories,the health evaluation grade of Tianshui Stadium in the construction process was finally confirmed to be "healthy".The practicality and effectiveness of naive Bayes classifier and Bayes network for health evaluation of this kind of structural system were verified by the field measurement and analysis of the stadium in each construction stage.The theory of dynamic monitoring system based on Bayesian network was proposed.It was proved that Bayesian network prior probability reasoning was feasible and effective in evaluating the safety of the same type of space tubular truss structure.