Structural Performance of Double Laminated Glass Panels with EVA and PVB Interlayer in Four-Point Bending Tests

Abstract

Many examples of glass loadbearing structures such as handrails, panes, beams and columns can be found in modern architecture. Most of these elements are made of laminated glass panels. There is a general lack of knowledge about the transfer of shear forces between the glass plies in perpendicularly-loaded laminated panels. This transfer depends significantly on the stiffness of the polymeric interlayer, which is timedependent and temperature-dependent. There are several computational methods for the design of laminated glass that take the shear coupling of the glass plies into account, e.g. analytical methods, numerical modeling and also the draft of European code. These methods need to be verified experimentally. This paper reports on rectangular double-laminated glass panels in a shortterm displacement controlled four-point bending test with an EVA and with a PVB interlayer under a constant temperature. These tests were performed at CTU in Prague. Our experimental results show that panels with an EVA interlayer had greater bending stiffness than panels laminated with PVB and achieved higher ultimate load values. The experimental data were further compared with simplified analytical methods, such as the European draft prEN 16612 and the Enhanced Effective Thickness approach and also a numerical FEM model. Numerical and EET methods results were in good agreement with the experimental data. The way in which the specimens broke was a characteristic feature of laminated glass. The shards remained attached to the interlayer, proving that laminated glass panels can be used safely above the heads of users of the structure. Simplified methods and numerical models validated by experimental tests on perpendicularly-loaded laminated glass panels enable these structures to be designed safely and economically for practical uses.

Elastic Critical Moment for the Lateral–Torsional Buckling (LTB) Analysis of Structural Glass Beams with Discrete Mechanical Lateral Restraints

“…Among the available interlayers [8], it is in fact generally recognized that that the mechanical response of a general laminated section is strictly related to the actual properties and bonding efficiency of these films [9,10]. As a result, refined methods of analysis and characterization should be generally taken into account, in the elastic stage [10][11][12] or in presence of possible degradation effects [13][14][15].…”

Advanced computational methods of perpendicularly loaded laminated glass panes

“…This density is a pre-set parameter and cannot be modified since this software was developed for quick engineering calculations. In spite of this, it is able to deliver reliable results (Hána, Eliášová, & Sokol, 2018). Geometric parameters of the illustrated pane used in all calculations are as follows: interlayer thickness t = 0.76 mm, thickness of glass plate h1 = h2 = 12 mm, horizontal dimensions 2500×2500 mm, Young's modulus of glass E = 70 GPa, Poisson's ratio of the interlayer ν = 0.45 and of glass ν = 0.23.…”

Numerical Evaluation of Slender Glass Panel with Complex Geometry Subjected to Static Load and Soft-body Impact

“…The glass panels create a glass room with an approximately height of 4.4 m and 15 × 6 m 2 in plan. Each glass panel with the dimensions of 0.99 × 4.38 m 2 consists of two 10 mm thick and fully toughened safety glass sheets laminated with 1.52 mm thick interlayer of Polyvinyl Butyral (PVB) [10]. The gap between panels is 10 mm.…”