Probability Analysis On Ultimate Load Of Lattice Shell With Initial Installment Imperfection

Because of the influence of construction level,the lattice shell inevitable existes initial installment imperfection,and this shall lead to the reducing of ultimate load.Especially for single-layer reticulated shell structures,the ultimate load of the defect is more sensitive to the initial installation.For different defects,the sensitivity of the structure is different,the key factors found to control the error during the installation process for improving the quality of construction has of great help.Therefore the study of the ultimate load of lattice shell with the initial imperfection have significant in practical engineering..(1) Using of MATLAB software for the geometric non-linear programming and Monte Carlo method combined with the introduction of the initial defect evaluate ultimate load,and draw the initial relationship between the defect and the ultimate load(2) Based on the finite element analysis software ANSYS,using Monte Carlo method with random defects in the structure get the probability distribution of ultimate load.(3) Use finite element analysis software ANSYS and response surface method for defects in hexagonal dome structure analysis to derive the critical loads.Compared methods of analysis of the Monte Carlo results with response surface method of CCD to draw some meaningful conclusions..The study included:For a large number of degrees of freedom with the spatial structure, use Monte Carlo methods to simulate random defects,and the response surface method can be regarded as a possible fast-track approach.For more of the spatial structure of random defects, process modeling and analysis in the introduction of variable factors,response surface analysis can be very good to find out which of these variables affecting the quality of the installation and find the key factors for improving the quality of engineering design.