RESEARCH ON KEY TECHNOLOGY OF RPC-NC COMPOSITE BEAM

Reactive powder concrete (RPC)-normal concrete (NC) composite T-shaped beam was proposed in this paper in order to promote the application of high performance material in modern bridge structures. This kind of composite beam could make the best of the high tensile strength and anti-cracking property of RPC and the effective properties against compression of NC. This composite beam could also make full use of the bonding property of RPC and NC, since they are both cement-based materials. This composite beam could achieve excellent mechanical property and decrease the cost of material, for a part of the beam is replaced by NC. We have been studying on the mechanical property of composite T-shaped beam through a series of modeling test and our aim is to apply it to practical engineering. RPC-NC double-sided shear specimens were designed and shear static loading test was carried out to explore the mechanical behavior of the interface in RPC-NC composite beam. T-shaped RPC-NC composite beams were designed and bending static loading test was conducted to explore the flexural property of T-shaped composite beam. Prestressed T-shaped RPC-NC composite beams were designed and bending static loading was carried out to investigate the flexural property of T-shaped composite beam with prestress. These bending loading tests both have control NC beam and the test results show that the flexural property of composite beam are better than NC beam. The fatigue test of prestressed T-shaped beam was carried out to explore the bending fatigue properties of RPC-NC composite beam. These test results could be the technical supports for the applying of the RPC-NC composite T-shaped beams into practical bridge engineering.