A Study on the Random Redistribution of Primary Curvature Imperfection and Different Members' Length on Bearing Capacity Double Layer Space Flat Grids for Different Support Conditions

Laboratory studies on double layer space flat grids revealed significant effects of kinds of imperfections on final bearing capacity. Most of theme is random imperfections such as initialcurvature of members, different member length or residual stresses of members; such a random imperfection effects on members bearing capacity and consequently on structure bearing capacity. So, considering the effects of random distribution imperfection is inevitable in assessing the actual failurebehavior of structures. The present paper aims to investigate the effect of random distribution of initialcurvature imperfection and different members' length on bearing capacity of double layer space flat grids for different support conditions. According to the structure's member, gamma and normal distribution random number were produces respectively for the initial curvature imperfection anddifferent members' length. So, there was a random imperfection across members. Using open sees and through nonlinear analysis the ultimate bearing capacity of structure was determined and the analysis was repeated several times based on Monte Carlo simulation method. At last charts and tables have been extracted based on maximum loading capacity obtained from the analysis. Findings revealed the sensitivity of double layer space flat grids to the Initial imperfections of random distribution for different support conditions.

کلیدواژه ها:

Double layer space flat grids ، Primary length and curvature imperfection ، Reliability ، Monte Carlo method ، Progressive Collapse