Sustainable construction material: Ultra-high performance fibre reinforced concrete (UHPFRC) for railway bridges in Malaysia

Abstract

UHPFRC is a new concrete technology being used in many countries including Malaysia. UHPFRC favourable material properties open up new potential for precast options in bridge construction and have been widely used as beams for highway bridges in Malaysia. Nevertheless, PRC beams were preferred despite heavy in weight and large sections although these properties affect the design of the bridge substructure as well the cost of construction. This research is to review the applicability of Grade 140/155 UHPFRC beam for railway bridges in Malaysia. Laboratory tests for mechanical properties of UHPFRC were conducted and results were verified and complied with the French Standard, NF P18-470: 2016. The characteristic cylinder and cube compressive strengths were 151 and 155 MPa while the tensile limit of elasticity, post-cracking tensile strengths and modulus of rupture were 7.8, 8.4 and 24.3 MPa respectively. Structural analysis and design as per NF P18-710: 2016 requirement was then performed for a 15 meter UHPFRC IB650 beam to justify its applicability against a Grade 40/50 PRC U-beam of an existing railway bridge in which the ultimate shear and moment capacities of both beams were compared. The ultimate shear and moment capacities of the 4 numbers of U-beams/deck were 4,092 kN and 13,324 kNm respectively and when compared to UHPFRC IB650 beam, six numbers/deck were required with ultimate shear and moment capacities of 4,836 kN and 14,574 kNm respectively. For durability, the modulus of elasticity and depth of water penetration for UHPFRC were 50.8 GPa and 2mm respectively compared to 34 GPa and 11mm for Grade 40/50 concrete.