Impact of Reinforcement Ratio on Shear Behavior of I-Shaped UHPC Beams with and without Fiber Shear Reinforcement

Abstract

In the presented paper, the impacts of steel fiber use and tensile reinforcement ratio on shear behavior of Ultra-High Performance Concrete (UHPC) beams were investigated from the point of different tensile reinforcement ratios. In the scope of the experimental program, a total of eight beams consisting of four reinforcement ratios representing low to high ratios ranged from 0.8% to 2.2% were casted without shear reinforcement and subjected to the four-point loading test. While half of the test beams included 30 mm end-hooked steel fibers (SF-UHPC) with 2.0 vol%, the remaining beams were produced without the fiber to show possible effectiveness of the fiber use. The shear performances were discussed in terms of the load—deflection response, cracking pattern and failure mode, first cracking load and ultimate shear strength. In this sense, all the non-fiber beams were failed by shear with a dramatic load drop, regardless of the tensile reinforcement amount, before the yielding of reinforcement and they produced no deflection capability. The test results showed that while the inclusion of steel fibers to the UHPC mixture with low reinforcement ratios changed the failure mode from the shear to flexure, it significantly enhanced the ultimate shear strength in the case of higher reinforcement ratio through the SF-UHPC’ superior mechanical properties and fibers’ crack-bridging ability.

Influencing Parameters of Exterior Reinforced Concrete Beam-Column Joint Shear Strength: A Depth Review of Recent Advances

“…Finally, FRP [68] has 2.01% of RR. Figure 3 shows the RR of various [51] and SCC [53] has 43% and 60.3% of DR. Then, FRP [54] has 47% higher DR than all other materials. Then, HCW-SC [68] has 40% of DR.…”

“…Yavas and Goker [54] illustrated the RR's impact on shear behaviors of I-shaped UHPC beams and devoid of fiber shear reinforcement. The outcomes displayed that the SS in higher RRs via the SF-UHPC's mechanical features along with fibers' crack-bridging capacity was advanced if the steel fibers' insertion to the UHPC mixture with lower RRs adjusted the failure mode as of the shear to flexure.…”

A Comparative Study on the Shear Behavior of UHPC Beams with Macro Hooked-End Steel Fibers and PVA Fibers

“…Although a series of studies have been performed to investigate the behavior of UHPC under shear loading, general agreement on the shear design and analysis methods for UHPC members has not been reached in the engineering community, mainly due to the lack of systematic studies. It is worth noting that among the almost 200 shear tests of non-prestressed beams made of advanced cementitious materials reported in the technical literature, only one beam had synthetic fibers [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. During almost the same period, engineered cementitious composite (ECC), which is another class of highperformance fiber-reinforced cementitious composite (HPFRCC), was developed [44][45][46][47][48][49].…”

Experimental analysis of steel fiber reinforced concrete beams in shear

“…Several studies have been developed with SFRC beams without stirrup reinforcement [5], [6], with the objectives of determining the main variables that control the shear behavior. Among these variables are the influence of steel fiber with different longitudinal reinforcement rates, Yavas and Goker [7] and the variation of the fiber volume, Resende et al [8]. According to Yakoub [2] increasing the steel fibers content may generate an increase in the shear strength and improve the beam ductility.…”