| | Category | EN | P14 | The Effects of Concrete Composition on Bridge Flexibility |
| | Abstract | The purpose of the experiment was to evaluate the effects of different |
| | compositions of the bridge deck on the resulting structure’s flexibility. The |
| | experiment was conducted using six unique combinations of cement, |
| | sand, water, lightweight aggregate, metakaolin, and two types of fibers |
| | called polyvinyl alcohol, PVA-1 and PVA-2. Each of the model decks was |
| | created using a mold in which the mixture was then allowed to set for one |
| | week to let the cement harden and achieve maximum strength. After each |
| | of the models was created, they were placed on supports to simulate the |
| | pillars of an actual bridge. Then, the amount of weight on each deck was |
| | progressively increased by pouring sand into a container placed in the |
| | center of the model. The total weight of the container of sand was then |
| | recorded when the model deck broke, which is the load capacity of the |
| | deck. The break in the model with a standard cement mix was clean and |
| | sudden because the material was very brittle, which is detrimental to |
| | bridge safety. The incorporation of lightweight aggregate and metakaolin |
| | improved the model deck’s flexibility. But the greatest flexibilities achieved |
| | were from the models with PVA fibers. Furthermore, the model containing |
| | PVA-1 performed better than the one containing PVA-2. Thus, not all |
| | fibers are equally effective in increasing a bridge’s flexibility. |
| | Bibliography | Beaulieu, David. “How to Mix Concrete.” |
| | About.com. February 20, 2009. |
| | http://landscaping.about.com/od/hardscapefences1/ht/mix_concrete.htm |
| | |
| | “Concrete Knowledge Center.” |
| | American Concrete Institute. February 20, 2009. |
| | http://www.conrete.org/tkc/CKC-Materials.htm |
| | |
| | Morrissey, Michael. “How Bridges Work.” |
| | April 1, 2000. HowStuffWorks.com. February 20, 2009. |
| | http://www.howstuffworks.com/bridge.htm |