TY - JOUR
T1 - Leaching characteristic and migration simulation of hazardous elements in recycled aggregates as subgrade scenario
AU - Ding, Le
AU - Zhang, Junhui
AU - Du, Qianhui
AU - Zhou, Chao
N1 - Funding Information:
The authors gratefully acknowledge the financial support offered by the Key Research and Development Project of Hunan Province ( 2022SK2082 ), Key Project of Scientific Research of Education Department of Hunan Province ( 22A0562 ).
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/9/25
Y1 - 2023/9/25
N2 - Recycling construction waste into subgrade materials is an effective way to build eco-friendly highways. To assess the saturation and leaching characteristics of recycled aggregates in subgrade application scenario, leaching tests were conducted, and a numerical model was used to analyze pollution migration. Results showed that three selected typical hazardous elements (Cd, Pb, and As) exhibited different characteristics in various physical conditions, but all their concentrations remained within safe limits. Moreover, the compaction degree demonstrated an inverse relationship with initial concentrations in the multilayer leaching process. During the migration of pollutants in the subgrade, pollutants accumulated near the slope initially and gradually diffused to the bottom, then penetrated into the foundation with a migration interface in an arc shape approximately, ultimately leading to a significant accumulation area with high concentrations. The initial concentration and subgrade dispersion coefficients showed opposite effects on the pollutants migration.
AB - Recycling construction waste into subgrade materials is an effective way to build eco-friendly highways. To assess the saturation and leaching characteristics of recycled aggregates in subgrade application scenario, leaching tests were conducted, and a numerical model was used to analyze pollution migration. Results showed that three selected typical hazardous elements (Cd, Pb, and As) exhibited different characteristics in various physical conditions, but all their concentrations remained within safe limits. Moreover, the compaction degree demonstrated an inverse relationship with initial concentrations in the multilayer leaching process. During the migration of pollutants in the subgrade, pollutants accumulated near the slope initially and gradually diffused to the bottom, then penetrated into the foundation with a migration interface in an arc shape approximately, ultimately leading to a significant accumulation area with high concentrations. The initial concentration and subgrade dispersion coefficients showed opposite effects on the pollutants migration.
KW - Hazardous elements
KW - Leaching characteristic
KW - Numerical simulation
KW - Pollution migration
KW - Recycled aggregates subgrade
UR - http://www.scopus.com/inward/record.url?scp=85167809102&partnerID=8YFLogxK
U2 - 10.1016/j.jclepro.2023.138270
DO - 10.1016/j.jclepro.2023.138270
M3 - Journal article
AN - SCOPUS:85167809102
SN - 0959-6526
VL - 420
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
M1 - 138270
ER -