Development of fiber-reinforced reactive magnesia cement composites
Ong, Nicole Shi Qi
Date of Issue2016-05-18
School of Civil and Environmental Engineering
Fiber-reinforced strain-hardening cementitious composites (SHCC) are commonly used in constructing new buildings and repairing deteriorating infrastructures. However, most SHCC have a high Portland cement (PC) content that requires high energy to produce and emits large amount of CO2 gas during production. On the other hand, reactive Magnesia (MgO) cement is able to sequester CO2 during hardening, hence it has a sustainability advantage over PC. Therefore, the focus of this study is to develop a fiber-reinforced MgO-based SHCC. Rheology tests were conducted to investigate the rheological properties of MgO-based SHCC and how it differs from PC-based SHC. It was found out that MgO-based SHCC behaved similarly to PC-based SHCC. It also provides adequate plastic viscosity that can improve tensile properties upon adequate carbonation and hardening. Single-fiber pullout tests were also conducted to study the bond between the fiber and matrix. It was revealed that PVA fibers with oil coatings performed better in composites in improving tensile properties. Findings from both tests were then used as a guide to design the MgO-based SHCC.
Final Year Project (FYP)
Nanyang Technological University