Double-Lap Shear Test Specimens

Three specimens for each type of epoxy adhesive used were fabricated, with nine specimens in total. It was decided to determine the shear bond strength

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Double-Lap Shear Test Specimens

b) Casting of UHPC for double shear bond test specimens

Double-Lap Shear Test Specimens

c) Casting of UHPC for tension pull-out specimens

FIG. 1—Fabrication of test specimens.

using double-lap shear specimens, due to the reduction in possible load eccen­tricities and misalignments during testing. The dimensions of the double shear test specimens are shown in Fig. 2. The instrumentation used for each specimen included ten strain gauges, with locations shown in Fig. 3, and two linear strain conversion transducers (LSCTs), which perform similarly to linear variable dis­placement transducers (LVDTs). The two LSCTs were used to measure the

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Downloaded/printed by

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Double-Lap Shear Test Specimens

FIG. 2—Dimensions for double-lap shear test specimens.

differential displacement between the GFRP plate and the UHPC prism on each side. A photograph of the final load setup is shown in Fig. 4.

For the purpose of clarity, experimental results as well as discussion of anal­ysis in this paper will refer to the end of the double shear test specimens with the protruding steel bar as the “fixed end"; the opposite end, which will be attached to the steel chair shown in Fig. 4, will be referred to as the “free end." In a similar fashion, the side with strain gauges SG-1 to SG-5 will be referred to as the “east side," whereas the side with strain gauges SG-6 to SG-10 will be called the “west side."

Tension Pull-out Specimens

Similar to the double-lap shear test specimens, three specimens were fabricated for each type of epoxy adhesive, resulting in a total of nine specimens. The

Double-Lap Shear Test Specimens

FIG. 3—Location of strain gauges on double-lap shear test specimens.

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Double-Lap Shear Test Specimens

FIG. 4—Double-lap shear specimen testing load setup.

dimensions for each specimen are shown in Fig. 5, with the load setup provided in Fig. 6. To prepare the specimens for testing, circular cuts were made with diameters of 50 mm. The cuts were initiated from the outer surface of the GFRP plate until an approximate depth of 5 mm into the UHPC layer was achieved. Steel discs, with a diameter of 50 mm and prepared with threaded holes through its center, were then bonded onto the outer surface of the GFRP plate. Through optimization arrangement, five individual pull-out tests were able to be performed on each specimen made, as shown in Fig. 5. The primary focus of these tests was the determination of the ultimate pull-out load as well as the

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Downloaded/printed by

Rochester Institute Of Technology pursuant to License Agreement. No further reproductions authorized.

Double-Lap Shear Test Specimens

mode of failure; therefore, only one load cell was used for data collection with­out the use of any strain gauges or LSCTs.