Record Details
The use of blended synthetic fibers to reduce cracking risk in high performance concrete (HPC)
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | The use of blended synthetic fibers to reduce cracking risk in high performance concrete (HPC) |
| Names |
Bañuelos, José
(creator) Ideker, Jason (advisor) |
| Date Issued | 2014-06-12 (iso8601) |
| Note | Graduation date: 2015 |
| Abstract | High Performance Concrete (HPC) is used in our crucial pieces of infrastructure, such as bridge decks, due to its enhanced durability and engineering properties. However, HPC is highly susceptible to early-age cracking. Cracking within the first months of a bridge deck’s lifespan can severely hinder its long-term performance and durability. Fiber reinforced concrete (FRC) is concrete with the incorporation of dispersed fibers. The main role of dispersed fibers is to control the crack opening and propagation; however, mixed results in literature suggest that FRC can reduce the total shrinkage of concrete. Therefore, the incorporation of blended sizes of synthetic fibers could provide resistance to shrinkage-related cracking. Cracking risk was evaluated using the restrained shrinkage ring test (ASTM C1581). The purpose of this study was to investigate the effect fibers on the fresh properties, mechanical properties, drying shrinkage, cracking risk, and durability (freeze-thaw and chloride ion penetrability) in HPC. In addition, recommendations on fiber dosages for use in the field were suggested. Moreover, there was an investigation on the effect of total cementitious material content, supplementary cementitious materials (SCM's), and aggregate type on the drying shrinkage of HPC. It was found that the inclusion of blended synthetic fibers reduced the cracking risk of HPC. The fibers did not reduce drying shrinkage; however, the time-to-cracking in the ring test was increased and crack widths were notably reduced. Fibers improved the freeze-thaw and chloride ion penetrability of HPC. A dosage rate between 5lb/yd³ and 7.5lb/yd³ is recommended. Additionally, using slag instead of fly ash in HPC also reduced the cracking risk. The use of limestone as a coarse aggregate showed the most significant reduction in in drying shrinkage and cracking risk. |
| Genre | Thesis/Dissertation |
| Access Condition | http://creativecommons.org/licenses/by-nc-nd/3.0/us/ |
| Topic | Fiber Reinforced Concrete |
| Identifier | http://hdl.handle.net/1957/50158 |
