Dr. Xunchang Fei obtained his PhD degree from the University of Michigan at Ann Arbor, USA, in 2015. He worked as a postdoctoral researcher at the University of Michigan in 2016 and at King Abdullah University of Science and Technology, Saudi Arabia, between 2016 and 2018. He joined Nanyang Technological University, Singapore in 2018. His main research areas are: (1) solid waste recovery, treatment, and management; and (2) geoenvironmental engineering. He received the 2021 Arthur Casagrande Professional Development Award from the American Society of Civil Engineers. He serves as a member of Technical Committee 215 of the International Society for Soil Mechanics and Geotechnical Engineering, and a member of the Geoenvironmental Engineering Technical Committee of the American Society of Civil Engineers.
Incineration bottom ash (IBA) holds attractive potential as a construction material, yet its shear behavior under cyclic loading remains insufficiently understood. This study comprehensively characterizes the monotonic and cyclic simple shear behavior of Singapore-derived IBA under constant volume conditions, with particular emphasis on its reuse potential in dynamic load-bearing applications. Key findings reveal that: (1) The material exhibits marked strain-hardening characteristics, demonstrating a density-dependent friction angle increment from 38.3° (loose state) to 42.5° (dense state). (2) Mechanical performance shows strong dependence on Si-Ca-Fe/Al ternary chemical composition and particle gradation characteristics. (3) Distinct failure modes emerge under different loading conditions - liquefaction dominates under unidirectional cyclic simple shear (UDCSS) conditions at low cyclic stress ratios (CSRs) and confining pressures, while bidirectional cyclic simple shear (BDCSS) loading induces cyclic mobility failure at elevated CSR levels, with corresponding cyclic resistance ratios (CRRs) showing a 30 % reduction in BDCSS compared to UDCSS configurations. (4) Pore pressure ratio (Ru) evolution follows a triphasic pattern: liquefaction failures exhibit rapid Ru acceleration in initial and tertiary phases (terminal Ru > 0.9), contrasting with cyclic mobility failures characterized by decaying Ru growth rates and lower terminal Ru values. (5) Notably, the established correlation between CRR and normalized shear wave velocity (Vs1) aligns closely with that of sand-gravel mixture with 5 % fines, which demonstrates the comparable cyclic load-bearing capacity of IBA to that of conventional construction materials. The study highlights the effect of load direction, particle size, and mineralogy in design applications and supports IBA's suitability for reuse in infrastructure subjected to dynamic loads.
| 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 |