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Summary of Numerical Load Results
| Name of beam | Concrete Compressive Strength [MPa] | CFRP Elastic Modulus [GPa] | CFRP Layers Number | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 25 | 40 | 55 | 165 | 240 | 640 | 1 | 2 | 3 | |
| BN-UST | 222.9 | 269.6 | 383.0 | 262.9 | 269 | 310.2 | 269.6 | 336.5 | 376.3 |
| BN-CST | 222.3 | 292.8 | 394.2 | 292.6 | 292.8 | 322.4 | 292.8 | 347.2 | 394.5 |
| BL-UST | 224.2 | 240.1 | 327.3 | 238.1 | 240.1 | 265.2 | 240.1 | 276.3 | 299.7 |
| BL-CST | 222.1 | 244 | 342.9 | 241.7 | 244 | 305.4 | 244.0 | 317.8 | 360.1 |
Mechanical properties of steel reinforcement_
| Yield strength [MPa] | Yield steel strain [µm/m] | Ultimate strength [MPa] | Ultimate steel strain [µm/m] | Elastic Modulus of Steel [GPa] |
|---|---|---|---|---|
| 510 | 2600 | 650 | 130000 | 196.154 |
Mechanical properties of concretes
| Type of Concrete | Concrete cube strength fcu [MPa] | Fflexural tensile of concrete fct [MPa] | Elastic modulus of concrete Ec [MPa] | Concrete density ρc [kg/m3] |
|---|---|---|---|---|
| NWC | 42.10 | 3.49 | 29860 | 2356 |
| LWC | 43.34 | 3.026 | 23510 | 1823 |
Summary of Numerical Deflection Results
| Name of beam | Concrete Compressive Strength [MPa] | CFRP Elastic Modulus [GPa] | CFRP Layers Number | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 25 | 40 | 55 | 165 | 240 | 640 | 1 | 2 | 3 | |
| BN-UST | 6.9 | 7.98 | 10.3 | 12.9 | 7.98 | 7.4 | 7.98 | 7.7 | 7.1 |
| BN-CST | 8.1 | 9.75 | 11.5 | 8.7 | 9.75 | 13.2 | 9.75 | 10.2 | 10.5 |
| BL-UST | 6.8 | 7.7 | 9.6 | 12.1 | 7.7 | 7.1 | 7.7 | 7.5 | 6.8 |
| BL-CST | 8.4 | 11 | 13.1 | 9.7 | 11 | 14.3 | 11 | 11.6 | 12.8 |
Experimental and numerical ultimate loads and mid-span deflections of LWC and NWC beams reinforced with CFRP sheets or strips
| Name of beam | EXP. Load [kN] | NUM. Load [kN] | Difference [%] (Load) | EXP. Def. [mm] | NUM. Def.[mm] | Difference [%] (Def.) | Failure mode | |
|---|---|---|---|---|---|---|---|---|
| EXP. | NUM | |||||||
| BN | 167 | 180 | 7.2 | 5.3 | 5.32 | 0.4 | Shear | Shear |
| BL | 151.36 | 165 | 8.3 | 4.85 | 4.7 | 3.1 | Shear | Shear |
| BN-UST | 257.84 | 269.12 | 4.2 | 7.69 | 7.98 | 3.6 | Shear+CFRP debonding | Shear+CFRP debonding |
| BN-CST | 320 | 292.32 | 8.6 | 10 | 9.75 | 2.5 | Shear+CFRP rupture | Shear+CFRP rupture |
| BL-UST | 222.38 | 240.13 | 7.3 | 7.2 | 7.7 | 6.5 | Shear+CFRP debonding | Shear+CFRP debonding |
| BL-CST | 254.2 | 244.32 | 3.8 | 11.59 | 11 | 5.1 | Shear+CFRP rupture | Shear+CFRP rupture |
Summary of failure mode Results
| Name of beam | Concrete Compressive Strength [MPa] | CFRP Elastic Modulus [GPa] | CFRP Layers Number | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 25 | 40 | 55 | 165 | 240 | 640 | 1 | 2 | 3 | |
| BN-UST | DSF | DSF | RSF | RSF | DSF | DSF | DSF | DSF | DSF |
| BN-CST | RSF | RSF | RSF | RSF | RSF | RSF | RSF | RSF | DSF |
| BL-UST | DSF | DSF | DSF | DSF | DSF | DSF | DSF | DSF | DSF |
| BL-CST | DSF | RSF | RSF | RSF | RSF | RSF | RSF | RSF | DSF |
Mechanical properties of CFRP reinforcement and primer resin
| CFRP reinforcement | |
| Modulus of elasticity [GPa] | 240 |
| Tensile stress [MPa] | 4000 |
| Failure strain [%] | 1.6 |
| Primer resin (Epoxy Plus) | |
| Compressive stress [MPa] | 100 |
| Tensile stress [MPa] | 19 |
| Flexural stress [MPa] | 30 |
| Bond to concrete [MPa] | > 5.3 |
| Modulus of elasticity [GPa] | 5 |