| 细粒土含量对粗粒硫酸盐渍土路基填料盐胀特性的影响试验及分析模型 |
| |
| 引用本文： | 王旭超,张莎莎,赵凯旋.细粒土含量对粗粒硫酸盐渍土路基填料盐胀特性的影响试验及分析模型[J].岩土力学,2022,43(8):2191-2202. |
| |
| 作者姓名： | 王旭超 张莎莎 赵凯旋 |
| |
| 作者单位： | 1.长安大学 公路学院，陕西 西安 710064；2.同济大学 土木工程学院，上海 200092 |
| |
| 基金项目： | 陕西省自然科学基础研究计划面上项目（No. 2019JM-147）；中国中铁重大科研项目（No. 2017-重大-11-04）。 |
| |
| 摘 要： | 为了明确细粒土含量对粗粒硫酸盐渍土路基填料盐胀量的影响，针对 1% 和 3%含盐量工况下的砂、砾类盐渍土，采用降温试验研究了细粒土含量递增条件下粗粒硫酸盐渍土的盐胀特点。在此基础上，利用 PFC3D技术模拟了粗粒盐渍土的盐胀变形并分析其机制，结合微观试验分析了盐胀状态中粗粒土骨架典型状态。结果表明：随着细粒土含量的增加，粗粒硫酸盐渍土的盐（冻）胀量均先增加后减少再增大，分界细粒土含量因含盐量及土类不同而异，1%、3% 含盐量的砂、砾类土样分别在15%和10%细粒土含量时产生最大盐（冻）胀量；3%含盐量砂、砾类土的起始盐胀温度约 20 ℃，1%含盐量土样的起始盐胀温度随细粒土含量及土种类不同差异较大且存在明显的界限细粒土含量，当细粒土含量低于界限值时土体的起始盐胀温度约为0.5～2 ℃，高于界限值时土体的起始盐胀温度约为 4～12 ℃；同时提出了盐胀状态中粗粒土骨架典型状态模型及其作为路基填料的细粒土含量界限值。
|
| 关 键 词： | 路基工程 粗粒盐渍土路基填料 盐胀 细粒土含量 |
| 收稿时间： | 2021-10-28 |
| 修稿时间： | 2021-12-21 |
Salt expansion characteristics and analysis model of coarse-grained sulfate saline soil embankment fill material with increasing fines content |
| |
| WANG Xu-chao,ZHANG Sha-sha,ZHAO Kai-xuan.Salt expansion characteristics and analysis model of coarse-grained sulfate saline soil embankment fill material with increasing fines content[J].Rock and Soil Mechanics,2022,43(8):2191-2202. |
| |
| Authors: | WANG Xu-chao ZHANG Sha-sha ZHAO Kai-xuan |
| |
| Institution: | 1. School of Highway, Chang’an University, Xi’an, Shaanxi 710064, China; 2. School of Civil Engineering, Tongji University, Shanghai 200092, China |
| |
| Abstract: | In order to clarify the influence of fine-grained soil
content on the salt expansion characteristics of coarse-grained sulfate saline
soil embankment fill material, sand and gravel saline soils with sulfate salt
contents 1% and 3% were investigated. A series of cooling and salt expansion
tests was carried out to examine salt expansion characteristic of
coarse-grained sulfate saline soil under conditions of increasing fines
content. On this basis, PFC3D discrete element method was adopted to
simulate salt expansion of coarse-grained sulfate saline soil, and typical soil
skeleton of coarse-grained saline soil during salt expansion process was
analyzed combining microscope tests results. The result shows that with the
increase of the content of fine-grained soil, the salt expansion/ frost heave
of coarse-grained sulfate saline soil first increases, then decreases and
increases finally. The boundary fines content varies with the salt content and
soil type. Sand and gravel soil samples with 1% and 3% salt content would
produce the largest salt expansion or frost heave at 15% and 10% fine-grained
soil contents respectively. The initial expansion temperature of sand and
gravel soil with 3% salt content is basically kept about 20℃. The initial expansion temperature of soil samples with
1% salt content varies greatly with the fines content and soil types, and there
exists an obvious limit of fines content. When the content of fine-grained soil
is lower than the limit value, the initial expansion temperature is about 0.5–2 ℃, when higher than the limit value, the initiation
temperature is about 4–12 ℃. A typical state model of the coarse-grained soil skeleton in the
salt-expansion state and the fines content limit of the coarse-grained sulfate
saline soil as the embankment filler are given. |
| |
| Keywords: | roadbed engineering coarse-grained saline soil embankment fill material salt expansion fine-grained soil content |
|
| 点击此处可从《岩土力学》浏览原始摘要信息 |
| 点击此处可从《岩土力学》下载免费的PDF全文 |
