关键词: 黄土, 石灰改良, 渗透特性, 击实试验, 电镜扫描, 庆阳市

Abstract: In order to study the influence of lime content on compaction and permeability of loess, the standard compaction test and variable head permeability test under different lime content and different dry density were carried out for loess samples collected at Qingyang City, Gansu Province. The test results showed that with the increasing of lime content, the maximum dry density drmax of the improved loess became smaller, and the corresponding optimal moisture content wopt became larger. When the lime content increased from 0 to 3%, the maximum dry density drmax decreased the most. The saturated permeability coefficient ksat of original loess and modified loess increased with the increasing of pore ratio e, and it is linear in semi-logarithmic coordinates, the fitting curves of different lime content were parallel to each other. Based on the results of scanning electron microscope, the qualitative and quantitative analysis of loess micro-structure showed that the numbers and area of large and medium-sized pores determined the loess permeability.

Key words: loess, lime amendment, permeability characteristics, compaction test, Scanning Electron Microscope, Qingyang City;