| Waste rubber powder | 40 Mesh | 60 Mesh | ||
| Unmodified | NaOH modified | Unmodified | NaOH modified | |
| 28 d flexural strength/MPa | 6.3 | 6.5 | 6 | 6.9 |
| 28 d compressive strength/MPa | 35.6 | 32.4 | 33.1 | 34.6 |