处置库污泥工程特性测试研究

对某填埋场污泥库中取样的污泥进行了岩土工程特性测试，包括有机质含量、含水率、界限含水率、颗粒级配、渗透系数、压缩固结特性及抗剪强度等。试验结果表明，与常规淤泥相比，污泥库中经一段时间降解后污泥有机质含量及含水率较高，平均值分别为45%和520%；污泥在历时2 a的生物降解作用下，污泥含水率、有机质含量沿深度呈较为明显的减少趋势；污泥具有极高的压缩性，压缩系数a100-200高达7 MPa-1；污泥的固结表现为非线性大变形特性，其固结系数在10-5～10-6 cm2/s，比淤泥低1～2个数量级，固结系数随压力的增加而显著减少；污泥的抗剪强度参数较小，其黏聚力为0，内摩擦角为14.7°。有机质含量高是污泥高含水率、高液塑性指数、高压缩性，低渗透性、低固结系数及低抗剪强度的本质原因。以上成果可为污泥库的固化处置、稳定分析等提供必要的参数。

Geotechnical properties measurement of sewage sludge at a disposal site

Laboratory tests are conducted to investigate geotechnical properties of sewage sludge in a sludge reservoir of a landfill, including organic content, water content, limit content, grain-size distribution, permeability coefficient, shear strength and consolidation coefficient. Test results show that the sewage sludge in the reservoir has much higher organic content and water content than the muddy soil. The average value of organic content is 45% and water content is 520%, respectively. As a result of biodegradation with a period of two years, both organic content and water content of the sewage sludge in the sludge reservoir show a decreasing trend with the depth. The sewage sludge had a very high compressibility, and the value of a100-200 is 7 MPa-1. The consolidation of the sewage sludge shows a nonlinear large deformation behavior; and the coefficient of consolidation is of the order 10-5-10-6 cm2/s, showing a significant decreasing trend with an increase of normal stress. The shear strength parameters are low with a cohesion of 0 kPa and an internal friction angle of 14.7°. The high organic content is the essential reason for the high values in water content, plasticity index and compressibility as well as the low values in permeability, consolidation coefficient and shear strength. The experimental results provide necessary parameters for the disposal of sludge reservoir and analysis of stability.