粘性土重塑方法分析与破碎性能比较

Comparison of Fragmentation Properties and Remolding Techniques for Clay Soil

对揉搓法与非标准普氏击制样方法进行对比,结果表明后者为土壤破碎机理研究提供了更多可控的土壤状态,同时土样的力学行为更为稳定,因此便于定量研究粘性土的密度、含水率、击实功、比冲击破碎能之间的关系。试验结果表明密度不能准确反映粘性土的粒间结合强度,而比冲击破碎能可以反映土粒间的结合紧密程度,这表明传统的以密度或者相对紧实度为参照的土壤耕作比阻预测方法需要改进。将非标准普氏击与冲击破碎测试相结合的试验结果表明,土样的比冲击破碎能随击实时土壤含水率的增大呈指数增长趋势,土壤破碎体的分形维数随含水率呈对数下降的规律。

Non-standard Proctor compaction as a soil remolding technique was compared with hand-rolling method. Non-standard Proctor compaction modified soil physical states in a large, stable and controlled manner, allowing the investigation of the co-relationship among soil density, water content, compacting work and specific soil fragmentation energy possible. It was found that density alone did not reflect cohesive soil compaction precisely; in contrary the specific fragmentation energy was more sensitive to inter-aggregate cohesion force. Therefore there is a need to refine the habit of using soil density or relative compaction as a proxy for modeling the specific traction in soil tillage research. The combined procedure of non-standard Proctor compaction and fragmentation test provided an increased exponential trend of specific fragmentation energy with respect to soil water content, while the fractal dimension of soil fragments decreased.