崩解性砂岩改良膨胀土的裂隙发育规律研究

文章以引江济淮项目膨胀土、崩解性砂岩为研究对象，利用崩解性砂岩对膨胀土进行改良，通过室内干湿循环试验研究干湿循环对砂岩改良土的裂隙宽度发展情况的影响。试验结果表明：在持续的水分蒸发过程中，砂岩改良土的裂隙宽度发展较均匀，持续的水分蒸发对砂岩改良土的影响较小；随着干湿循环次数的增加，砂岩改良土的蒸发速率和残余含水率变化幅度较小，改良后土体水分蒸发受干湿循环的影响减小；随着干湿循环次数的增加，砂岩改良土裂隙最大宽度、裂隙平均宽度、宽度峰值差的变化幅度较纯膨胀土平缓，掺入砂岩后，膨胀土裂隙发育受干湿循环影响减小。

Study on fracture development of expansive soil improved by disintegrated sandstone

The expansive soil and disintegrated sandstone of the diversion project from the Yangtze River to the Huaihe River are taken as the research objects. The disintegrated sandstone is used to improve the expansive soil. Through the indoor dry-wet cycle test, the influences of the dry-wet cycle on the strength characteristics and fracture development of the improved sandstone soil are studied. The test results show that in the process of continuous water evaporation, the crack width of sandstone improved soil develops more evenly, and the influence of continuous water evaporation on sandstone improved soil is small; with the increase of dry-wet cycles, the variation ranges of evaporation rate and residual water content of sandstone improved soil are small, and the influence of dry-wet cycles on the moisture evaporation of improved soil is reduced; with the increase of dry-wet cycles, the variation ranges of the maximum crack width, average crack width and peak crack width difference of the improved soil are more gentle than those of the expansive soil without improvement.