Table 8 Results of Energy absorption and stiffness
Beam | Energy absorption (EA) | Stiffness (k) | |||||||
|---|---|---|---|---|---|---|---|---|---|
EAi (kN.mm) | Change in EAi (%) | EA (kN.mm) | Change in EA (%) | Failure | ki (kN/mm) | Change in ki (%) | k (kN/mm) | Change in k (%) | |
Group I: effect of existing opening, concrete type, replacement of traditional stirrups by WWM | |||||||||
 A1 | 32.3 | 0.0 | 486 | 0.0 | S | 11.2 | 0.0 | 5.0 | 0.0 |
 A2 | 42.5 | 31.6 | 278 | −42.8 | S | 6.8 | −39.2 | 4.5 | −10.0 |
 B1 | 33.3 | 3.2 | 2334 | 380.2 | F | 5.9 | −47.4 | 4.4 | −12.0 |
Group II: effect of filling material type at tension side | |||||||||
 B1 | 33.3 | 0.0 | 2334 | 0.0 | F | 5.9 | 0.0 | 4.4 | 0.0 |
 B2 | 22.7 | −32.0 | 2370 | 1.5 | F | 9.9 | 68.9 | 6.2 | 40.9 |
 B3 | 10.4 | −68.9 | 2262 | −3.1 | F | 21.7 | 269.6 | 7.5 | 70.5 |
Group III: effect of filling material type at centroid of the section | |||||||||
 C1 | 2.6 | 0.0 | 2114 | 0.0 | F | 40.0 | 0.0 | 23.0 | 0.0 |
 C2 | 2.7 | 6.7 | 2248 | 6.3 | F | 38.0 | −5.0 | 21 | −8.7 |
 C3 | 5.9 | 129.4 | 1438 | −32.0 | S-F | 32.0 | −20.0 | 19.2 | −16.5 |
Group IV: effect of hole shape (circular in C2 and rectangular in C4) | |||||||||
 C2 | 2.7 | 0.0 | 2248 | 0.0 | F | 38.0 | 0.0 | 21 | 0.0 |
 C4 | 37.8 | 1291.2 | 538 | −76.1 | S | 12.8 | −66.3 | 9.3 | −55.7 |
Group V: effect of hole number | |||||||||
 B1 | 33.3 | 0.0 | 2334 | 0.0 | F | 5.9 | 0.0 | 4.4 | 0.0 |
 D1 | 31.5 | −5.5 | 2122 | −9.1 | F | 6.0 | 2.0 | 4.2 | −4.5 |
Group VI: effect of filling material type at compression side | |||||||||
 D1 | 31.5 | 0.0 | 2122 | 0.0 | F | 6.0 | 0.0 | 4.2 | 0.0 |
 D2 | 22.6 | −28.4 | 2522 | 18.9 | F | 5.4 | −10.6 | 4.4 | 4.8 |
 D3 | 20.8 | −34.0 | 1976 | −6.9 | F | 5.8 | −3.0 | 4.6 | 9.5 |