Grouted mixture exhibits excellent anti-rutting performance, but its low-temperature crack resistance is inadequate, and the influence of the interfacial contact parameters between the aggregate skeleton and the grouting material on the crack resistance is not yet clear. To clarify the low-temperature fracture characteristics of grouted mixture and the influence of the interfacial micromechanical parameters between the aggregate skeleton and the grouting material on crack resistance, a discrete element numerical simulation model of grouted mixture was established using discrete element method. The micromechanical parameters were calibrated through real low-temperature bending tests. The interfacial failure mechanisms and characteristics during the fracture process were analyzed. Subsequently, the interfacial micromechanical contact parameters between aggregate skeleton-aggregate skeleton or aggregate skeleton-grouting material were adjusted to investigate the changes in crack resistance performance indicators of grouted mixture under different parameter conditions. Results indicate that the majority of cracks in grouted mixture are tensile cracks (accounting for 87.0%), predominantly occurring at the interface between aggregate skeleton and grouting material. Reducing the bond elastic modulus both between aggregate skeleton and between the aggregate skeleton and grouting material, increasing the interfacial bond tensile strength between the aggregate skeleton and grouting material, can enhance the crack resistance of the grouted mixture. However, reducing the bond elastic modulus leads to an increase in the number of microcracks within the grouted mixture. Among these parameters, the interfacial bond tensile strength between aggregate skeleton and grouting material has the most significant impact on crack resistance. When the interfacial bond tensile strength is increased by 50.0%, the flexural tensile strength of grouted mixture increases by 25.1%, the maximum flexural tensile strain increases by 29.3%, and the number of cracks decreases by 20.0%. The study provides a reference for optimizing the crack resistance performance of grouted mixture.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |