宁夏中部干旱带粗颗粒土裂化过程研究

Study on cracking process of coarse-grained soils in central dry zone of Ningxia

为探究压砂地粗颗粒土裂化过程,以粗颗粒砾石(灰绿板岩)为研究对象,通过开展室内模拟试验,测定冻融干湿作用下粗颗粒砾石理化性质,利用电镜扫描观测不同处理下粗颗粒砾石细观形貌,初步分析粗颗粒砾石在冻融干湿交替循环作用下裂化进程。结果表明,随循环次数增加,粗颗粒产生明显裂化行为,2 mm粗颗粒砾石其破碎程度越大产生岩屑越多,并伴随矿物质元素释放。淋溶液中电导率EC值随循环次数增加呈递增趋势,说明粗颗粒中矿物离子释放,溶解于淋溶液。文章从宏观和微观角度分析粗颗粒裂化规律,揭示粗颗粒裂化机理,为进一步研究土壤粗颗粒成壤化提供理论支持。

In order to investigate the cracking process of coarse-grained soils in pressed sand,coarse-grained gravels(grey-green slate)were used as the objects of study.The physical and chemical properties of coarse-grained gravels under the action of freeze-thaw dry and wet were measured through indoor simulation tests,and the fine morphology of coarse-grained gravels under different treatments was observed by electron microscopy scanning.The results showed that the coarse gravels showed significant fracturing behaviour as the number of cycles increased,with the coarse gravels of 2 mm producing more rock chips with greater fragmentation and the release of mineral elements.The EC values in the drench solution increased with the number of cycles,indicating that the mineral ions in the coarse grains were released and dissolved in the drench solution.The analysis of the coarse particle cracking pattern from macroscopic and microscopic perspectives revealed the mechanism of coarse particle cracking and provided theoretical support for further research on soil coarse particle loam formation.