Ultra-high performance fiber-reinforced concrete (UHPFRC) is a highly promising material that exhibits superior
compressive strength, resistance to tension, flexural strength, toughness, and durability in comparison to conventional
concrete. This study examines the effectiveness of prefabricated UHPFRC laminates in shear strengthening reinforced
concrete (RC) beams. To attain elevated standards and expedite the enhancement procedure of on-site apps, it has been
suggested to utilize the prefabricated UHPFRC laminates as a strengthening layer bonded to the concrete surface by
using steel dowels and/or epoxy. A total of nine reinforced concrete beams were subjected to a four-point loading test
until failure. One beam was selected as a control beam without strengthening, while the other eight beams were
strengthened by various schemes. The following key parameters were investigated: the number of strengthening sides,
the thickness of the UHPFRC layer, the reinforcement of the strengthening layer (by using two different types of steel
mesh, and also, in case of no-steel mesh), the volume fraction of steel fibers, and bonding schemes steel dowels and/or
epoxy. The test results demonstrate that using the UHPFRC prefabricated laminates provides an efficient method for
improving RC shear performance. The ultimate load and ductility of the strengthened beams have increased up to 45.6
and 76 %, respectively, compared with the unstrengthened beam. It has been found that using an epoxy bonding system
performs more effectively than adding steel dowels. The ultimate load was raised by 7 and 12.5 % where epoxy bonding
system is applied only for laminates thickness of 15 and 30 mm, respectively, on both sides (with 2 % steel fiber)
compared with specimens where steel dowels were added. As expected, the results also revealed that using the
strengthening layer with reinforcement provides better shear performance than using UHPFRC layers without reinforcement.
Using welded and expanded steel meshes in the strengthening layer increased the ultimate load by 39 and
41.5 %, respectively, in the case of a 15 mm strengthening layer on both sides with 2 % steel fiber. Increasing the steel
fiber ratio in the UHPFRC mixture from 2 to 3 % increases the ultimate load slightly by only 5.7 %.