Influencing factors of the plate glass columns on the load bearing capacity

The initial imperfection of the structural elements must be taken into account in case of the modern building designing. These imperfections are local or overall defects of the glass elements. These defects are able to reduce significantly the load bearing capacity and the stability limits as well. The initial curvature and the imperfections of the elements are taken into account at the stability designing in case of the general building materials. The applied limits depended on the cross-section of the structural elements. Glass designing for load bearing elements has been applied since a few decades, however there are limits for initial imperfections. More than 240 small scaled i-shaped glass columns were loaded until fracture under laboratory conditions. The lateral buckling was investigated based on the individual experimental procedure. One of the most important properties of the glass columns are the initial imperfections. The higher overall bow and roller wave values can cause disadvantages at the load bearing capacity of the glass columns; however, the roller waves also can increase the critical buckling force according to Euler. These specific factors of the glass specimens were measured by a new measurement method to analyse the effects of the imperfections on the load bearing capacity in case of a small amount of the specimens. The new method contains a Reference Point System and it is able to detect these imperfections in high accuracy. The new measurement method is also able to provide information about the glass manufacturing effects on the plate glass shape.