Huie Chen, Hua Du, Haotian Guo, Fansheng Kong, Zhongqiong Zhang
{"title":"非饱和冻土的冻结应变特性和机制:母吸力和水冰相变分析","authors":"Huie Chen, Hua Du, Haotian Guo, Fansheng Kong, Zhongqiong Zhang","doi":"10.1007/s11440-024-02359-z","DOIUrl":null,"url":null,"abstract":"<div><p>The freezing strain characteristics of unsaturated soil are quite different from those of saturated soil. Besides the commonly observed frost heave, unsaturated soil may also experience frost shrinkage, causing uneven surface deformation and deterioration of soil properties. Matric suction and water–ice phase change are key factors affecting the freezing strain characteristics of soil. In this study, the freezing strain characteristics and underlying mechanisms of lean clay samples with different initial matric suctions at varying temperatures were investigated. A mathematical relationship between soil temperature and matric suction was established, enabling the estimation of variation trends in matric suction. The internal mechanisms of different freezing strain characteristics were analyzed based on the mesoscopic structures of frozen samples with low and high initial matric suctions. The results showed that samples with low initial matric suction and frozen at low negative temperatures are prone to frost heave. Frost heave occurs when the volume expansion of the soil caused by water–ice phase change exceeds the volume reduction due to increased matric suction; otherwise, frost shrinkage occurs. The morphology of pore ice in samples with different initial matric suctions varies, reflecting the degree of water–ice phase change in the soil. Using the Pearson correlation coefficient method, an empirical model for axial freezing strain applicable to unsaturated frozen lean clay was established, and the model’s validity was confirmed with experimental data.</p></div>","PeriodicalId":49308,"journal":{"name":"Acta Geotechnica","volume":"19 11","pages":"7243 - 7260"},"PeriodicalIF":5.6000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Freezing strain characteristics and mechanisms of unsaturated frozen soil: analysis of matric suction and water–ice phase change\",\"authors\":\"Huie Chen, Hua Du, Haotian Guo, Fansheng Kong, Zhongqiong Zhang\",\"doi\":\"10.1007/s11440-024-02359-z\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The freezing strain characteristics of unsaturated soil are quite different from those of saturated soil. Besides the commonly observed frost heave, unsaturated soil may also experience frost shrinkage, causing uneven surface deformation and deterioration of soil properties. Matric suction and water–ice phase change are key factors affecting the freezing strain characteristics of soil. In this study, the freezing strain characteristics and underlying mechanisms of lean clay samples with different initial matric suctions at varying temperatures were investigated. A mathematical relationship between soil temperature and matric suction was established, enabling the estimation of variation trends in matric suction. The internal mechanisms of different freezing strain characteristics were analyzed based on the mesoscopic structures of frozen samples with low and high initial matric suctions. The results showed that samples with low initial matric suction and frozen at low negative temperatures are prone to frost heave. Frost heave occurs when the volume expansion of the soil caused by water–ice phase change exceeds the volume reduction due to increased matric suction; otherwise, frost shrinkage occurs. The morphology of pore ice in samples with different initial matric suctions varies, reflecting the degree of water–ice phase change in the soil. Using the Pearson correlation coefficient method, an empirical model for axial freezing strain applicable to unsaturated frozen lean clay was established, and the model’s validity was confirmed with experimental data.</p></div>\",\"PeriodicalId\":49308,\"journal\":{\"name\":\"Acta Geotechnica\",\"volume\":\"19 11\",\"pages\":\"7243 - 7260\"},\"PeriodicalIF\":5.6000,\"publicationDate\":\"2024-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Acta Geotechnica\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s11440-024-02359-z\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, GEOLOGICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Acta Geotechnica","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11440-024-02359-z","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}
Freezing strain characteristics and mechanisms of unsaturated frozen soil: analysis of matric suction and water–ice phase change
The freezing strain characteristics of unsaturated soil are quite different from those of saturated soil. Besides the commonly observed frost heave, unsaturated soil may also experience frost shrinkage, causing uneven surface deformation and deterioration of soil properties. Matric suction and water–ice phase change are key factors affecting the freezing strain characteristics of soil. In this study, the freezing strain characteristics and underlying mechanisms of lean clay samples with different initial matric suctions at varying temperatures were investigated. A mathematical relationship between soil temperature and matric suction was established, enabling the estimation of variation trends in matric suction. The internal mechanisms of different freezing strain characteristics were analyzed based on the mesoscopic structures of frozen samples with low and high initial matric suctions. The results showed that samples with low initial matric suction and frozen at low negative temperatures are prone to frost heave. Frost heave occurs when the volume expansion of the soil caused by water–ice phase change exceeds the volume reduction due to increased matric suction; otherwise, frost shrinkage occurs. The morphology of pore ice in samples with different initial matric suctions varies, reflecting the degree of water–ice phase change in the soil. Using the Pearson correlation coefficient method, an empirical model for axial freezing strain applicable to unsaturated frozen lean clay was established, and the model’s validity was confirmed with experimental data.
期刊介绍:
Acta Geotechnica is an international journal devoted to the publication and dissemination of basic and applied research in geoengineering – an interdisciplinary field dealing with geomaterials such as soils and rocks. Coverage emphasizes the interplay between geomechanical models and their engineering applications. The journal presents original research papers on fundamental concepts in geomechanics and their novel applications in geoengineering based on experimental, analytical and/or numerical approaches. The main purpose of the journal is to foster understanding of the fundamental mechanisms behind the phenomena and processes in geomaterials, from kilometer-scale problems as they occur in geoscience, and down to the nano-scale, with their potential impact on geoengineering. The journal strives to report and archive progress in the field in a timely manner, presenting research papers, review articles, short notes and letters to the editors.