In this study, characteristics of the long-term landfill settlement are analysed and the starting date of residual settlement is deduced using the data of the landfill 1 of the Gimpo Metropolitan Landfill (GML) measured for 27 years. The landfill 1 is a multi-staged municipal solid waste landfill where dykes are constructed after landfilling for subsequent waste fills. The landfilling began in 1992 and finished in 2000, and the waste settlement measurement continued throughout this period. The older waste of the lower lift shows higher biodegradation and larger settlement than the waste of the upper lift, which acts as vertical load. Large settlement occurred in the lower lifts due to the collapse of waste voids caused by the overburden load of the upper lifts after biodegradation of waste in the lower lifts during long-term landfilling. In the conventional landfills, that is, mono-layer landfills, the time-dependent settlement generally occurs after the stress-dependent settlement. But, most of the time, this landfill showed mainly the time-dependent settlement. The duration, at which the biodegradation of organic matters is reduced and the residual settlement begins, was 8.8 years in average and the date range was from 7.6 to 11.7 years considering each disposed block in landfill 1. This date is obtained by calculating from the mid-point time of the landfilling duration.

本研究利用金浦都市填埋场（GML）填埋场 1 的 27 年测量数据，分析了长期填埋场的沉降特征，并推导了剩余沉降的开始日期。垃圾填埋场1是一个多级城市固体垃圾填埋场，填埋后建造堤坝，用于后续的垃圾填埋。填埋工作于 1992 年开始，2000 年完成，垃圾沉降测量在此期间继续进行。较老的下层垃圾比上层垃圾表现出更高的生物降解性和更大的沉降，后者起到垂直荷载的作用。长期填埋过程中，下层垃圾生物降解后，上层土层负荷过大，导致下层垃圾空隙塌陷，导致下层出现大面积沉降。在常规填埋场，即单层填埋场中，时变沉降一般发生在应力沉降之后。但是，大多数时候，这个垃圾填埋场主要表现出与时间相关的沉降。有机物生物降解减少和残留沉降开始的持续时间平均为 8.8 年，日期范围为 7.6 至 11.7 年，考虑到垃圾填埋场 1 中的每个处置块。该日期是从年中计算得出的。 -填埋持续时间的点时间。