古土壤层间富水对黄土场地湿陷性的影响
The influence of moisture-rich interlayers in palesol strata on the collapsibility of loess terrain
李琳 1王家鼎 1谷琪 1张登飞 1焦少通1
作者信息
- 1. 西北大学地质学系/大陆动力学国家重点实验室,陕西西安 710069
- 折叠
摘要
黄土地层中往往交替分布着多层红色古土壤层,由于其硬度相对较高,遇水不易湿陷,对黄土地层湿陷量的测量结果有很大的影响.然而,对于古土壤对湿陷量的控制作用目前还缺乏相关研究,导致对湿陷地层湿陷量的科学取舍缺乏理论依据.为此该文统计了黄土高原区的浸水试验结果,分析了不同区域湿陷量室内外差异特征,并以西安地区两个试验场地的大型浸水试验为研究对象,进行了不同试验条件下土体中水分的扩散、含水率的变化、土压力变化以及累计湿陷量等测量工作.最终结果表明,古土壤层的存在阻碍湿陷进程,在阻止水分下渗的同时,阻碍深部地层湿陷量传递至地表,使得湿陷量实测值与计算值之间的差异与古土壤层数呈现正相关的趋势.该文将为普遍存在古土壤的黄土地层自重湿陷机理的研究提供参考.
Abstract
In loess formations,multiple layers of reddish ancient soil often alternate.Due to their relatively high hardness,they are resistant to collapsing when exposed to water,which significantly impacts the measure-ment results of the collapsibility of loess formations.However,there is currently a lack of research on the con-trolling role of ancient soils in collapsibility,leading to a lack of theoretical basis for making scientific deci-sions on the collapsibility of geological formations.To address this gap,this study compiled the results of inun-dation tests in the Loess Plateau region,analyzed the indoor and outdoor differences in collapsibility character-istics in different areas,and focused on large-scale inundation tests in two experimental sites in Xi'an.Vari-ous aspects were measured under different test conditions,including moisture diffusion in the soil,moisture content changes,soil pressure variations,and cumulative collapsibility.The final results indicate that paleosol-layers hinder the collapsibility process by impeding water infiltration and preventing the transmission of deep-seated collapsibility to the surface.This leads to a positive correlation between the measured collapsibility val-ues and the number of ancient soil layers.This study aims to provide insights into the self-weight collapsibility mechanisms in loess formations where ancient soil layers are commonly found.
关键词
古土壤/浸水试验/湿陷性/湿陷系数/黄土Key words
paleosol/inundation test/collapsibility/collapsibility coefficient/loess引用本文复制引用
基金项目
国家自然科学基金重大仪器研制项目(42027806)
国家自然科学基金重点项目(4160639)
西北大学研究生创新项目(CX2023012)
出版年
2024
NETL
NSTL
万方数据