Page 13 - Open-Access-June-2020

TECHNICAL PAPER

7. FLEXURAL BEHAVIOR OF ECC 7.1.1 Load carrying capacity
STRENGTHENED RC BEAMS
Strengthened ECC beams without reinforcement showed
It is anticipated that the tensile load carrying capacity and strain- enhanced load carrying capacity than unstrengthened beam
hardening behavior of ECC can be exploited for strengthening without reinforcement owing to the strain-hardening behavior
[59]
applications in RC beams. Application of ECC in the tensile of ECC in the tension zone . Compared to unstrengthened
RC beam, the ECC strengthened RC beam showed enhanced
zone of RC beams [58-60] enhances the load carrying capacity,
load carrying capacity due to the higher ultimate tensile
failure mode, cracking behavior, stiffness and ductility. Hence,
strength of ECC layer [63,64] . The ultimate load carrying capacity of
many studies have investigated the flexural performance of ECC strengthened beams greatly increased with the introduction of
strengthened RC beams (see Table 6). Strengthening application small amount of steel reinforcement in ECC layers .
[65]
of ECC for RC slabs was also studied .
[61]
7.1.2 Stiffness and Ductility
7.1 Flexural Behavior of ECC Strengthened RC
Before initial crack, the stiffness of strengthened and
Beams unstrengthened plain beams was similar. However, after the
occurrence of initial crack, the stiffness of strengthened plain
While understanding the flexural behavior of ECC strengthened
beam was higher than unstrengthened plain beam due the
RC beams utmost importance to be given to the parameters
strain-hardening behavior of ECC . Strengthened RC beams
[66]
such as influence of ECC layer thickness along with beam
showed enhanced stiffness compared to unstrengthened
reinforcement ratio, stiffness, ductility, failure modes, and RC beams owing to the greater cracking load . Despite the
[65]
cracking behavior. Hence, noteworthy research studies from the type of reinforcement used (i. e. steel/FRP) the deflection
literature are discussed in accordance with the above-mentioned of strengthened composite beams was less than that of
parameters. Fig. 3 shows the schematic diagram of typical ECC unstrengthened concrete beams for same loading due to the
strengthened RC beam . presence of ECC .
[62]
[62]

Figure 3: Schematic Diagram of Typical ECC Strengthened RC Beam .
[62]

14 The IndIan ConCreTe Journal | June 2020