The Utilization of Glass as a Cost-Effective, Compressive Compositing Material in Structural Applications; Finite Element Modeling and Physical Testing
In this presentation, we will display our findings on a cost-competitive compositing method that utilizes glass as a compressive reinforcement in a polymer-based beam. This is dissimilar to glass-fiber composites as the glass is utilized as a compact rod or sheet that is placed in the compressive side of the designed composite beams as opposed to being distributed throughout the beam. By concentrating the glass, the glass will be maximally loaded, contributing greatly to the beam’s strength. Glass is known to have a compressive strength of 1000 MPa (144 ksi), which can be paired with a polymer acting as a binder and steel as a tensioning material to make what we refer to as a triple composite beam. Due to glass’ elevated compressive strength, glass manufacturing produces less CO2, contains less embodied energy, and has a lower cost than concrete, steel, or structural timbers when compared on a per strength basis. When the glass is utilized in an analytically designed composite beam, economic costs are within 5% (including manufacturing costs) that of steel when compared on a deflection-basis and maintain a safety factor of 50% above steel. Additionally, there are no upkeep costs associated with maintaining the triple-composite beams as they are fully coated in polymer while steel requires painting on a regulated basis. If a design disregards deflection, the compositing beam can be produced for 36% less cost than a steel structural shape. However, the beams designed under these conditions can deflect significantly (6 inches of deflection in 20 feet). The specific analytical method utilized for determining beam stresses and deflections is the method of transformed sections, which is based on the Euler Bernoulli beam theory. Finite element modeling has been conducted to support our analytical findings. The analytical calculations are within 10% of the finite element modeling determined stresses while maintaining a standard deviation of 2%. We’ve also performed physical testing. Physical testing conducted has indicated that glass can be maximally stressed to 65% of its compressive strength before debonding, and failure of the triple-composite-beam occurs. Despite this lower strength value, it makes no difference in the analytical solutions as the beams designed typically have glass stresses at most of 600 MPa. When a deflection-based design is pursued, the glass stresses will be approximately 160 MPa. Essentially, glass, while having an impressive compressive strength, is difficult to attain the maximum glass stresses due to the low Young’s modulus of soda-lime glass. This, however, can lead to a very conservative design that features significantly higher safety factors (e.g., up to 5) than are possible with equivalent cost steel structures. The recommended manufacturing method for these glass-polymer-steel beams would be a plastic extrusion process using pressure tooling in an over jacketing extrusion process. We will also present physical testing results conducted thus far utilizing a polyurethane casting method for the production of test beams.
The Utilization of Glass as a Cost-Effective, Compressive Compositing Material in Structural Applications; Finite Element Modeling and Physical Testing
Category
Poster Presentation
Description
Session: 17-01-01 Research Posters - On Demand
ASME Paper Number: IMECE2020-23582
Session Start Time: ,
Presenting Author: Rasim Guldiken
Presenting Author Bio: Rasim Guldiken is an Associate Professor and Graduate Program Director of Mechanical Engineering Department at University of South Florida.
Authors: John Cotter University of South Florida
Rasim Guldiken University of South Florida