Strength Design Methods for Laminated Glass

University dissertation from Structural Mechanics, Lund University

Abstract: In this thesis, methods for efficiently determining stresses in laminated glass structures are developed and tested. The laminated glass structures comprise both bolted and adhesive joints. A recently developed finite element is suggested to be suitable for the modeling of laminated glass structures. The element is implemented and tested. It is proven by means of a simple test example that the element can be used in finite element analysis of laminated glass structures and give a good accuracy with a small fraction of the corresponding model size using standard solid elements. As an illustration of how the element would perform when more complicated glass structures are concerned, a similar element is implemented in the commercial finite element software ABAQUS and is used to analyze a laminated glass structure comprising one bolt fixing. The element performs well both when it comes to accuracy and efficiency. It is indicated that the new finite element is well suited for modeling laminated glass structures. The new finite element is rigourously tested and compared to standard solid elements when it comes to the modeling of laminated glass structures. It is shown that the new finite element is superior to standard solid elements when it comes to modeling of laminated glass. The new element is applied to laminated glass structures comprising bolted and adhesive joints. Good results concerning accuracy and efficiency are obtained. The results show that the element may well be suited to model complex laminated glass structures with several bolted or adhesive joints. The new element is used in the development of a method to compute stress concentration factors for laminated glass balustrades with 2+2 bolt fixings. The stress concentration factors are represented graphically in design charts. The use of the design charts allow the maximum principal stresses of the balustrade to be determined without using finite element analysis or advanced mathematics. The stresses can be computed for an arbitrary combination of geometry parameters of the balustrade. It is illustrated how design charts for laminated glass balustrades with 3+3 bolt fixings are developed. Keywords: finite element, computational techniques, laminated glass, stress