25 Detection and Evaluation of Vascular Network Based …
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Fig. 25.3 Example of the Load-CMOD graphs for control specimen (grey curve) and 24 h selfhealing (blue curve) specimen through the whole testing process
25.3.1 Strength Regained Ratio of Self-Healing Concrete
The results of the initial loading test (before the injection of healing agent) and the
reloading test (after healing agent is injected and cracks are healed) are shown in
Table 25.1. The control beams (C1 to C3) were already failed after the first threepoints bending test. Therefore, the strength fell by an average of around 75% in the
reloading process.
However, those specimens which were healed by cyanoacrylate with different
healing time (1-h, 24-h, and 3-days) carried further loading in the reloading test.
Table 25.1 Mechanical results of initial loading and reloading
Healing agent Specimen
No.
1st
loading/kN
Time of
pause
2nd
loading/kN
Strength
recovery/%
Average/%
No
C1
6.55
No
1.73
26.4
25.5
C2
6.11
1.47
24.1
C3
6.13
1.59
25.9
Cyanoacrylate
PC 20
SH-A1
6.67
1-h
4.44
66.
66.8
SH-A2
6.09
4.36
71.6
SH-A3
5.98
3.72
62.2
SH-B1
7
24-h
4.81
68.7
65.9
SH-B2
7.02
4.76
67.8
SH-B3
6.2
3.81
61.5
SH-C1
5.27
3-days
4.71
89.4
80.6
SH-C2
6.18
4.92
79.6
SH-C3
5.35
3.9
72.9