Field investigation of ultra-high performance concrete shear key in an adjacent box-girder bridge

Corrosion at steel beam ends is one of the most pressing challenges in the maintenance of aging bridges. To tackle this challenge, the Connecticut Department of Transportation (DOT) has partnered with the University of Connecticut to develop a repair method that benefits from the superior mechanical and durability characteristics of ultra-high performance concrete (UHPC) material. The repair involves welding shear studs to the intact portions of the web and encasing the beam end with UHPC. This provides an alternate load path for bearing forces that bypasses the corroded regions of the beam. The structural viability of the repair has been extensively proven through small- and full-scale experiments and comprehensive finite element simulations. Connecticut DOT implemented the repair for the first time in the field on a heavily trafficked four-span bridge in 2019. The UHPC beam end repair was chosen because of the access constraints and geometric complexities of the bridge that limited the viable repair options. Four of the repaired beam ends were fully instrumented to collect data on the performance of the repaired locations before casting, during curing, and for approximately 6 months following the application of the repair. This paper provides an overview of the successful repair implementation and presents the lessons learned during construction. Select data from the monitored beam ends are presented. It is expected that this information will provide engineers with a better understanding of the repair implementation process, and thus provide an additional repair option for states to enhance the safety of aging steel bridges.

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Prefabricated Box Girder with Ultra High Performance Concrete

IABSE Conference, Kuala Lumpur 2018: Engineering the Developing World ◽

10.2749/kualalumpur.2018.0744 ◽

2018 ◽

Author(s):

Keli Xiao ◽

Yanjun Jin ◽

Lin Li ◽

Wei He ◽

Duan Xinlong

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Slab Thickness ◽

Low Carbon ◽

Ultra High Performance Concrete ◽

Dead Weight ◽

Box Girder ◽

Ordinary Concrete ◽

Shear Connectors ◽

Thin Beams

<p>In order to solve traffic difficulty brought by the bridge construction in the city, and difficult transportation of beams, this paper puts forward the prefabricated-box-girder bicycle viaduct with ultra - high performance concrete (UHPC) through which will achieve light and thin beams, easy transportation and rapid construction. Based on the bicycle viaduct with 5.5m in width, this paper not only designs a prefabricated ribbed thin-walled box girder with 30m in span, including the detailed design of prefabricated segment stiffeners, shear connectors and external prestressing but also compares the UHPC box girder with ordinary concrete box girder and steel box girder. The research shows that with the application of UHPC in prefabricated viaduct in city, the ratio of height to span of beams and the slab thickness decrease to 1/30 and 10cm respectively, the dead weight is 50% lower than that of the ordinary concrete beams and the 3m long lifting weight is only 10 tons. Light and thin beams are suitable for transportation in city because of their low requirements for transportation and hoisting equipment. UHPC beams have no steel bars and own the advantages of dense texture, good durability, low maintenance costs, reflecting the concept of low carbon environmental protection and green bridge.</p>

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Traffic Forces and Temperature Effects on Shear Key Connections for Adjacent Box Girder Bridge

10.15554/pci.rr.tran-002 ◽

2002 ◽

Cited By ~ 2

Author(s):

Xuhua Dong

Keyword(s):

Temperature Effects ◽

Box Girder ◽

Shear Key ◽

Box Girder Bridge ◽

Girder Bridge

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Implementing Ultra High Performance Concrete (UHPC) with Dowel Bars in Longitudinal Joints (Shear Key) in an Adjacent Box Beam Bridge

10.21838/uhpc.2016.71 ◽

2016 ◽

Cited By ~ 2

Author(s):

Eric P. Steinberg ◽

Ali A. Semendary ◽

Kenneth K. Walsh

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Ultra High Performance Concrete ◽

Shear Key ◽

Box Beam ◽

Longitudinal Joints ◽

Beam Bridge

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Testing of High-Performance Concrete Single-Span Box Girder

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1624-14 ◽

1998 ◽

Vol 1624 (1) ◽

pp. 118-124 ◽

Cited By ~ 1

Author(s):

R. Miller ◽

B. Shahrooz ◽

T. M. Baseheart ◽

E. Long ◽

J. Jones ◽

...

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Highway Bridges ◽

Modulus Of Rupture ◽

Test Beam ◽

Transfer Length ◽

Box Girder ◽

State Highway ◽

Girder Bridge ◽

Section Analysis

As part of a multistate research program on use of high-performance concrete (HPC) in highway bridges, a bridge originally designed as a three-span adjacent box girder bridge was converted to a single-span bridge by using 70-MPa HPC and 15-mm strands. As part of the research, a test beam was constructed and tested. Instruments placed in the beam before casting were used to measure transfer length, which was found to be approximately 1.22 m, larger than the 50-bar diameters usually used in the American Association of State Highway and Transportation Officials (AASHTO) Standard Specifications but consistent with recent studies. After the beam concrete reached the required compressive strength, it was tested to destruction. The beam was able to resist the required AASHTO ultimate moment without failure. It was found that the AASHTO cracking load was conservative for this beam, mostly because the measured modulus of rupture greatly exceeded the value assumed in the AASHTO specifications. The behavior of the beam was successfully predicted using a section analysis.

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