High Performance Fiber Reinforced Cementitous Composites (HPFRCC) which were defined as fiber reinforced cementitious composites exhibiting strain hardening behavior in tension were developed in this study. Two kinds of HPFRCC which named Engineering Cementitious Composites (ECC) and High Strength Fiber Reinforced Cementitious Composites (HSFRCC) were investigated. ECC is a HPFRCC to give a high ductility. To study the potential application of ECC as a pseudo ductile protective layer on external wall or canopy, ECC that can be plastered of 5-10mm thickness on concrete wall was developed. Experimental tests (Beam push-out test and Concrete panel test) demonstrating the deformability were performed. To overcome the high drying shrinkage of ECC which may weaken the interfacial bond between...[ Read more ]

High Performance Fiber Reinforced Cementitous Composites (HPFRCC) which were defined as fiber reinforced cementitious composites exhibiting strain hardening behavior in tension were developed in this study. Two kinds of HPFRCC which named Engineering Cementitious Composites (ECC) and High Strength Fiber Reinforced Cementitious Composites (HSFRCC) were investigated. ECC is a HPFRCC to give a high ductility. To study the potential application of ECC as a pseudo ductile protective layer on external wall or canopy, ECC that can be plastered of 5-10mm thickness on concrete wall was developed. Experimental tests (Beam push-out test and Concrete panel test) demonstrating the deformability were performed. To overcome the high drying shrinkage of ECC which may weaken the interfacial bond between the layer and concrete substrate, shrinkage reducing ECC using calcium sulfoaluminate cement was studied. Experimental results demonstrated the successful application of ECC as a protective layer to prevent the sudden falling of spalled concrete which was very dangerous in a city with many tall concrete blocks such as Hong Kong. HSFRCC is the other kind of HPFRCC which gives high mechanical load carrying capacities. In this study, HSFRCC is proposed as a joining material for pre-cast concrete slabs with small joint size. Self compacting HSFRCC was first developed. Direct Tension Pull-out Bond Test (DTP-BT) was then conducted to study the bond behavior between deformed bar and HSFRCC. Finite element study was performed to verify the mechanism of cracking propagation. Bending test of HSFRCC joined pre-cast concrete slabs was conducted to compare the structural performance of HSFRCC joined slab and monolithic concrete slab. Experimental results showed the feasibility of using HSFRCC in the construction of joints for pre-cast concrete members.