苏州七子山填埋场竖向扩建飞灰填埋库区实践

Practice of Horizontal Expansion of Qizishan Landfill in Suzhou for Fly Ash Disposal

苏州七子山填埋场是我国最早在生活垃圾堆体之上竖向扩建飞灰填埋库区的填埋场之一,其飞灰填埋库区采用了双层人工合成材料防渗衬层,至今已运行10余年,累计填埋飞灰4.996×10^(5)t。对该填埋场库底土压力和沉降持续跟踪监测。结果表明:飞灰填埋厚度约8.0 m时,库底测得土压力为81.44 kPa;库区基层产生了显著的沉降和不均匀沉降,最大沉降量为1.79 m,最大不均匀沉降量为2.26 m。竖向扩建飞灰填埋库区建设完成后,垃圾堆体稳定安全系数为1.814,目前为1.472,均满足规范要求。竖向扩建飞灰填埋库区的基层沉降问题需要在设计和运行阶段充分考虑和应对。

Suzhou Qizishan landfill is one of the earliest landfills in China to vertically expand the fly ash landfill area above the domestic waste pile.The fly ash reservoir area adopted a double-layer artificial synthetic material anti-seepage lining layer.It has been running for more than 10 years,with a total of 499600 tons of landfill fly ash.The subsoil pressure and settlement of the landfill reservoir were tracked and monitored.The results showed that when the thickness of fly ash landfill was about 8.0 m,the soil pressure at the bottom of the reservoir was 81.44 kPa.The base of the reservoir area had produced significant settlement and uneven settlement.The maximum settlement is 1.79 m,and the maximum uneven settlement was 2.26 m.After the completion of the construction of the vertical expansion fly ash landfill reservoir area,the stability safety factor of the garbage pile was 1.814,which is currently 1.472,which meets the requirements of the specification.The settlement of the base layer in the vertical expansion of the fly ash landfill reservoir area needs to be fully considered and dealt with in the design and operation stages.