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TECHNICAL PAPER
160
Experimental, B-1 Experimental, B-2
Energy ratio = 85.9% Energy ratio = 92%
120
Load (kN) 80
40
0
160
Experimental, B-3 Present approach
Energy ratio = 73.4% Energy ratio = 89.6%
120
Load (kN) 80
40
0
3
2
00 100 200 30 0 0 10 20 30
1
Deflection (mm) Deflection (mm)
Figure 8: Energy ratios for the BFRP-PSC beams tested and theoretically obtained from the present design approach
as elastic linear material, by specifying its elastic modulus,
Poisson’s ratio, ultimate tensile strength, and plastic strain at Loading wedges
failure. For the BFRP tendons, the ultimate tensile strength was
defined as 1116 MPa, the plastic strain was defined close to
zero as 10 , and the elastic modulus was defined as 50.84 GPa.
–5
The elastic modulus and Poisson’s ratio of the steel, used for Assembly
stirrups, were defined as 210 GPa and 0.3, respectively. All
the reinforcements were embedded inside the concrete host
element. The prestressing forces were applied as initial stresses
to the tendons in the predefined field. The prestressing forces
here were 60% (669.6 MPa) of the ultimate tensile strength of the Support pin
BFRP tendons as applied in the experimental work, and were Mesh
equal to the effective prestressing forces after accounting for
the prestress losses in the present design approach. Thus, the
comparison of the results obtained from (a) experimental work,
(b) present analytical design approach, and (c) finite element-
based numerical simulation was made for the same total
prestressing force of 669.6 MPa. The numerical simulation was
carried out in four stages such as (i) prestressing applied, (ii) self- Reinforcement cage
weight imposed, (iii) applied load before reaching the ultimate
load-carrying capacity, and (iv) loading in the post-peak stage.
The displacement-control loading was applied to capture the
failure of the beam and its behavior in the post-peak stage. The
finite element (FE) model of the beam developed in ABAQUS Figure 9: Finite element (FE) model of the BFRP-PSC beam in ABAQUS
®
®
environment is shown in Figure 9. environment
THE INDIAN CONCRETE JOURNAL | JANUARY 2021 25
