Resistant Performance Of Standing Seam Metal Roof System Under Fluctuating Wind Uplift

Standing seam metal roof system is widely used in many large-span space structures due to it is excellent performance.The current methods for evaluating the adequacy of metal roofs in withstanding wind-induced loads involve undertaking uniform uplift pressure tests.However,the wind-induced damage accident of the roofing system designed based on the static test results still occurs,indicating that these methods cannot accurately reflect the real ultimate bearing capacity of standing seam metal roof system.It is of practical significance to study the mechanical behavior of standing seam metal roof system under fluctuating wind uplifit.This paper presents results of a full-scale experimental study of standing seam roof system conducted under fluctuating wind loading.We found the staged reponse of the standing seam metal roofing system under fluctuating wind load.The main contents of this paper are as follows:(1)Based on the relevant domestic and international standards,a test program for the standing seam metal roofing system under fluctuating wind uplift was developed.The uniaxial tensile test of the panel material 3004H24 aluminum-magnesium-manganese alloy that commonly used in engineering was completed.The material properties of the alloy were obtained.(2)The dynamic wind-resistant test of the six kinds of standing seam metal roof system commonly used in the project was completed,and the mechanical performance and ultimate damage of the roof system at different load levels were obtained.By analyzing the relevant experimental data,the cumulative damage effect of the upright seam metal roofing system under dynamic wind loads was discussed.The effects of wind-resistant fixtures,plate width and purlin spacing on wind bearing capacity were studied and discussed.(3)Dynamic numerical simulation is currently unable to obtain the desired calculation results.Therefore,we compare the test results with the previous static test results and static numerical simulation results,and found that the ultimate bearing capacity measured by the dynamic loading test is reduced by about 20%,and the failure mode is also changed.The phase response mechanism of the upright seam metal roofing system under dynamic wind load is discussed.Based on this,the damage degree of the roofing system is divided into: intact,medium damage,severe damage,damage,and the corresponding criterion is determined.