Research on flexural behavior of the externally prestressed UHPC box girder

Abstract

Experiment on an externally prestressed ultra high performance concrete (UHPC) box girder subjected to symmetrical concentric loads is carried out. The behavior of the test girder is investigated, including the load-deflection curve at mid-span, cracking pattern, strain distribution, and failure mode. The mid-span nominal moment capacity of the girder is analyzed. Test results show that the anti-cracking capacity of UHPC box girder is better than that of a normal prestressed concrete (PC) girder. The tensile property of UHPC should be taken into account in the process of calculating mid-span nominal moment capacity of the externally prestressed UHPC box girder. Finite element (FE) model analysis results agree well with the test results. The influencing parameter, concrete grades, was studied numerically to compare the flexural behavior of UHPC girder with PC girder. The cracking moment and ultimate load calculation method is proposed, which can meet precision for engineering practice and can be a reference method for design calculation of a prestressed UHPC box girder.

Full-scale bending test and parametric study on a 30-m span prestressed ultra-high performance concrete box girder

“…The ultimate moment resistance can be obtained according to the equilibrium condition, as illustrated in equation (6), in which the ultimate tensile strength f t is multiplied by a reduction factor. The reduction factor β is suggested as 0.8 by Su et al (2017) for safer design.…”

“…Due to its proven structural efficiency, durability and life-cycle cost-effectiveness, researchers, designers, and contractors raised the standard of quality by designing and constructing the entire slab-on-girder bridge system of UHPC. Few researchers conducted experimental testing on developed UHPC girders to investigate their strength for use in highway bridges (Chen and Graybeal, 2011; Hassan et al, 2012; Kahanji et al, 2017; Qi et al, 2018; Su et al, 2017; Voo et al, 2015; Yang et al, 2011; Yoo et al, 2017). Their research proved that the use of UHPC in precast/prestressed concrete girders enables a significant increase in the bridge span of the slab-on-girder bridge when compared with conventional normal strength concrete bridge girders.…”

Study on reinforcement effect of H type assembled anchoring joint in portal frame

“…Among many reinforcement methods, the external prestressing reinforcement technology is convenient, cost saving, and thus has been increasingly applied to reinforce the steel structures (Abbas et al, 2018; Kambal and Jia, 2018; Yang et al, 2012), concrete structures (Herbrand and Classen, 2015; Marco, 2018; Su et al, 2017; Wang, 2009; Zhang et al, 2018), bridge constructions (Chen et al, 2017; Madaj and Mossor, 2019; Miyamoto et al, 2000; Park et al, 2004; Zhao et al, 2014) etc. For example, Kambal and Jia (2018) tested the strength of two steel box girders (prestressed girder and control girder), and verified that prestressing techniques can enhance steel girders flexural behavior.…”