关键词: 腐殖土, 高龄期填埋场, 理化性质, 资源化利用, 无侧限抗压强度, 道路填筑材料

Abstract: The humus soil of an aged landfill in Jishui county was taken as the research object to explore the physics-chemistry properties and leaching solution, in order to provide an effective way for its resource utilization. The results showed that the content of lime soil, brick and stone components in waste humus was as high as 93.62%, and the content of glass and plastic was 6.38%. The humus was sandy soil with good thermal stability. The results of XRD and EDS showed that the main chemical components were SiO2, Al2O3, FeO and CaCO3, while the main mineral components were quartz, calcite and so on. The content of organic matter in humus was 15.4%. Heavy metals including chromium,zinc and arsenic exceeded the standard,and the leaching concentration of arsenic and plumbum also exceeded the standard in different degrees. The pH of humus after curing by lime-cement was greater than 12, which was beneficial to accelerate the decomposition of organic matter. Its unconfined compressive strength was 1.7-3.1 MPa, while the total content of lime and cement more than 10% could meet the filling requirements of JTG D50—2017 Specifications for Design of Highway Asphalt Pavement for medium and light traffic base and subbase of secondary and below secondary roads, which had the potential to be used as road filling materials.

Key words: humus, aged landfill, physical and chemical properties, resource utilization, unconfined compression strength, road filling materials