Joint Behavior of Ultra-High Performance Fiber Reinforced Concrete Beam

Abstract

This article presents behavior of reinforced concrete beam using four-point bending test which the beam-to-beam is connected with ultra-high performance concrete (UHPC) and non-shrink concrete. The objective of the study is to evaluate the performance of the connection in transferring the force at the beam and to observe the effect the connection on critical area. The specimen has a dimension of length 700 mm x width 150 mm x height 150 mm. The dimension of the specimens is chosen considering the size of the concrete form and the loading frame. The design compressive cylinder strength chosen is 320 ksc at 28 days air curing. Deformed steel bars with nominal diameter of db is equal to 12 mm of SD40 grade are used as tension member. Test parameters are bar overlapping length and ration of UHPC with depth of beam. The middle-span connection consisting of the overlapping lengths of 3db, 6db and 9db. Three different UHPC thickness varying from 50 mm, 75 mm and 100 mm of the beam depth. In total, 30 specimens are cast and tested with 3 specimens of each condition. Failure mode, crack pattern and load-slip response are recorded and discussed under the different test parameters. Results of the study overlap And the depth that can receive the most force is 85.05 kN in the span at 9 times the diameter of the steel reinforcement, 100 mm deep, but the strength is 43 less than that of the unconnected beam, which is 148.11 kN. percent