Effects of elevated temperature and simulated environmental conditions on the properties of epoxy based polymer resin

Timms, Ashlii (2015) Effects of elevated temperature and simulated environmental conditions on the properties of epoxy based polymer resin. [USQ Project]

[img]
Preview
Text
Timms_A_Manalo.pdf

Download (7Mb) | Preview

Abstract

Concrete is the most widely used material in structural engineering. However, when exposed to Australia’s climate, concrete can suffer stress, shrinkage cracking and deterioration. These harsh environmental conditions include excessive heat, moisture, alkalinity, and high humidity (hygrothermal environment). Thus, there is a need to determine and investigate new materials that has the potential to replace concrete in severe environmental conditions.

Epoxy is a commercially available polymer that has historically been used for crack repair and coating due to its known high strength and durability properties. However, epoxy- based polymer concrete is uneconomical and inconvenient for large civil infrastructures. The use of fillers practically reduces the price of epoxy based polymer and has been found to improve the mechanical properties. However, little research has been done to understand the effect of filers on the temperature sensitivity and durability of epoxy based polymers. This project analyses the effect of light-weight particulate filler has on the thermomechanical and durability properties of epoxy resin, with respect to simulated environmental conditions.

To achieve the research objectives, the project was divided into two studies. Study 1 was conducted to determine the optimal filler content, with respect to elevated temperature, that had no significant reduction in the compressive strength of the epoxy resin. Compression testing from room temperature to 80◦C and physical observations were con- ducted. Study 2 aimed at evaluating the six-month durability of the optimal mix selected from Stage 1 at different simulated environmental conditions. The samples were exposed to either air, saltwater, water or hygrothermal environment. Changes in the compressive strength, appearance, dimensions, weight and microscopic structure were observed at pre-set intervals.

From Study 1 it was concluded that the optimal mix design was determined to be the 60:40. There was an overall decrease of 90.2% and 96.4% in peak stress and Youngs modulus respectively. Minimal voids were present on the specimens and compressive failure was an evenly distributed shear failure. While the 40:60 specimens had an overall decrease of 85.2% and 92.1% in peak stress and Youngs modulus respectively, the mixture can create issues in actual application due its low workability, voids and brittle compressive failure.

From Study 2 it was concluded that the optimal mix design meets six month durability ex- posed to simulated environmental conditions. Dimensions remained consistent and there was no more than 0.3% water absorption. With the increase of duration all specimens had an increase in peak stress, with air having a 38% increase.

For the specimens exposed to the water and salt-water environments the same trends were presented with the increase of duration. Therefore the salt had no effect on the durability of the specimens. For the specimens exposed to the hygrothermal environment, the elevated temperature resulted in post curing. After 7 days exposure, the peak stress had an increase of 20%, which was 12% higher than the specimens exposed to the other environments. Therefore the filler had no adverse effects on the durability of the specimens.


Statistics for USQ ePrint 29240
Statistics for this ePrint Item
Item Type: USQ Project
Item Status: Live Archive
Additional Information: Bachelor of Civil Engineering project
Faculty / Department / School: Current - Faculty of Health, Engineering and Sciences - School of Civil Engineering and Surveying
Supervisors: Manalo, Allan
Date Deposited: 06 Jun 2016 04:39
Last Modified: 06 Jun 2016 04:39
Uncontrolled Keywords: Epoxy, Filter, Durability
Fields of Research : 09 Engineering > 0905 Civil Engineering > 090599 Civil Engineering not elsewhere classified
URI: http://eprints.usq.edu.au/id/eprint/29240

Actions (login required)

View Item Archive Repository Staff Only