Investigating fracture mechanics and flexural properties of unsaturated polyester polymer concrete (UP-PC)

Polymer concretes are particle composites of polymers which are filled by aggregates. Polyesters, epoxies and acrylics have been used as binders in these materials which polyesters due to their suitable properties and acceptable cost are considered by the most of industries. One of the most considered issues about polyester polymer concretes is their weak performance and the low durability against acids and alkaline solutions. In this research, fracture mechanics (CMOD and K1c) and flexural strength (σ) of a polyester polymer concrete after 1, 3, 6 and 12 months of exposure to sulfuric acid 0.5and1mollit and carbonate/bicarbonate alkaline solution 0.0622and0.1245mollit were investigated. Results showed that both of aggressive solutions degraded polymer concrete samples. However acids caused more decrement in flexural strength and alkaline had more destructive effect on fracture mechanics. Furthermore, the concentration was more important in destructive effects especially for alkaline solution. The highest decrease in flexural strength, fracture toughness and CMOD were 37%, 36.1% and 59% respectively. SEM analysis was used to assess morphological changes accrued at fractured surfaces of the samples.