填埋场封场后的次沉降计算

探讨了封场后填埋场的沉降机理以及填埋体中有机质的降解规律,提出了在分析填埋场封场后的沉降时应单独考虑由于填埋体降解引起的体积减少的观点。提出了分析有机质降解引起的沉降的理论模型,并利用该模型解释了实测中出现的在次压缩后期沉降对数曲线斜率增大的现象。在理想条件下,填埋场的降解沉降为最终降解沉降和一衰减项的乘积。填埋场的最终降解沉降率取决于填埋体的可降解有机质含量和一无量纲数M,其物理含义为降解速率与填埋时间的乘积;而衰减项则是填埋体降解速率和时间的函数。

Calculation of post-closure settlement of landfills

The settlement mechanism of post closure landfills and the decomposition rule of organic carbon for MSW are discussed in this paper. The opinion that the settlement induced by biodegradation should be considered separately is put forward. A model of analyzing the biodegradation settlement is presented and is utilized to explain the increase of slope of settlement-logt curves observed in situ. It is concluded that under ideal circumstance, the biodegradation settlement can be expressed as a product of final biodegradation settlement and an attenuation factor. The final biodegradation settlement rate is determined by the content of biodegradable organic carbon and a dimensionless parameter, which is the product of biodegradation rate and filling time. The attenuation factor, is determined by the biodegradation rate and time.