1 Introduction
2 Experimental Work
2.1 Materials and Mix Proportions
Type | Density (kg/m3) | Water absorption (%) | Crushing value (%) |
---|---|---|---|
Natural aggregate | 2752 | 1.12 | 4.00 |
Recycled aggregate | 2633 | 3.25 | 13.42 |
Cement | Water | Aggregate | Additive | w/c | |
---|---|---|---|---|---|
NAPC | 368 | 110 | 1425 | 23.4 | 0.30 |
RAPC | 368 | 110 | 1363 | 23.4 | 0.30 |
2.2 Molding and Curing of Specimen
2.3 Loading Method
3 Experimental Results and Analysis
3.1 Static Bending Strength
No. | NAPC | RAPC |
---|---|---|
1 | 4.01 | 3.26 |
2 | 4.23 | 3.08 |
3 | 4.21 | 3.35 |
Average | 4.15 | 3.23 |
3.2 Failure Mode
3.3 Hysteresis Loop
Groups | Stress levels | Cycle ratios | ||
---|---|---|---|---|
0.1 | 0.5 | 0.9 | ||
NAPC | 0.75 | 9.12 | 11.62 | 12.67 |
0.8 | 11.49 | 12.32 | 15.16 | |
0.85 | 23.68 | 28.74 | 43.42 | |
0.9 | 46.01 | 58.07 | 130.50 | |
RAPC | 0.75 | 7.90 | 12.58 | 17.13 |
0.8 | 14.03 | 18.59 | 31.40 | |
0.85 | 21.82 | 28.09 | 42.28 | |
0.9 | 23.22 | 33.19 | 69.21 |
3.4 Damping Ratio
Groups | Stress levels | Cycle ratios | ||
---|---|---|---|---|
0.1 | 0.5 | 0.9 | ||
NAPC | 0.75 | 1.08 | 1.27 | 1.29 |
0.8 | 1.45 | 1.53 | 1.64 | |
0.85 | 2.46 | 2.52 | 3.11 | |
0.9 | 3.47 | 3.79 | 5.8 | |
RAPC | 0.75 | 1.39 | 1.77 | 2.05 |
0.8 | 1.67 | 2.01 | 2.74 | |
0.85 | 2.36 | 3.17 | 4.02 | |
0.9 | 3.07 | 3.58 | 4.75 |
3.5 Dynamic Elastic Modulus
3.6 Total and Plastic Strains
4 Fatigue Life Prediction Model
Group | Elastic modulus/GPa | Peak strain/με |
---|---|---|
NAPC | 24.880 | 265.88 |
RAPC | 18.228 | 379.93 |
4.1 Fracture Parameter
Group |
a
1
|
b
1
|
R
2
|
---|---|---|---|
NAPC | |||
Pre-peak | 0.005 | 0.27 | 0.99 |
Post-peak | 0.002 | 0.95 | 0.99 |
RAPC | |||
Pre-peak | 0.0017 | 1.75 | 0.98 |
Post-peak | 0.0017 | 2.5 | 0.99 |
4.2 Plastic Strain
Group |
a
2
|
b
2
|
R
2
|
---|---|---|---|
NAPC | |||
Pre-peak | 2.86 | 0.35 | 0.99 |
Post-peak | 4.04 | 0.23 | 0.99 |
RAPC | |||
Pre-peak | 1.78 | 0.57 | 0.99 |
Post-peak | 4.04 | 0.20 | 0.99 |
4.3 Loading Cycles
Group | Parameters | ||
---|---|---|---|
A | B | C | |
NAPC | 15.00/(1.20Smax)−11.6 | 11.6 (1.25Smax)5.7 | (1.37Smax)16.5 |
RAPC | 10.85/(1.25Smax)−7.0 | 19.0 (1.15Smax)2.5 | (1.50Smax)10.5 |