应力作用下黄泛区粉土的孔隙特征研究  

Study on pore characteristics of silt in the Yellow River flood area under stress

作　　者：王鹏 王海 孙利琴 应本林 程熙洋 李永辉[2] WANG Peng;WANG Hai;SUN Liqin;YING Benlin;CHENG Xiyang;LI Yonghui(China Railway Seventh Group Zhengzhou Engineering Co.,Ltd.,Zhengzhou 450052,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;School of Engineering,China University of Geosciences,Wuhan 430079,China)

机构地区：[1]中铁七局集团郑州工程有限公司,河南郑州450052 [2]郑州大学土木工程学院,河南郑州450001 [3]中国地质大学工程学院,湖北武汉430079

出　　处：《四川建筑科学研究》2025年第2期60-69,共10页Sichuan Building Science

基　　金：河南省自然科学基金面上项目(222300420555)。

摘　　要：为探究应力作用下黄泛区粉土孔隙特征的变化规律及应力作用影响机制,开展了不同应力状态下黄泛区粉土扫描电镜(scanning electron microscopy,SEM)和核磁共振(nuclear magnetic resonance,NMR)试验与分析。结果表明:应力作用不会改变黄泛区粉土的双峰孔隙结构;在较低正应力(0~200 kPa)作用下,黄泛区粉土存在一个临界正应力,在临界正应力前后,其孔隙特征参数随应力作用变化趋势相反;应力作用对黄泛区粉土集聚体间孔隙的影响大于对集聚体内孔隙的影响;随着应力作用增大,集聚体间孔隙总体积减小,其中孔径大于优势孔径的集聚体间孔隙体积首先减小;随着应力作用增大,集聚体内孔隙总体积增大,其中孔径小于优势孔径的集聚体内孔隙体积增大较为明显。In order to explore the variation law of pore characteristics of silt in the Yellow River flood area under the influence of stress and the influence mechanism of stress,SEM and NMR tests of silt in the Yellow River flood area under different stress states were carried out.The results show that the stress does not change the bimodal pore structure of silt in the Yellow River flood area.Under the action of lower normal stress(0-200 kPa),the silt in the Yellow River flood area has a critical normal stress.Before and after the critical normal stress,the variation trends of pore characteristic parameters with stress are opposite.The effect of stress on the inter-aggregate pores is greater than that on the intra-aggregate pores of silt in the Yellow River flood area.With the increase of stress,the total volume of inter-aggregate pores decreases,and the inter-aggregate pore volume whose pore size is larger than the dominant pore size decreases first.The total volume of intra-aggregate pores increases with the increase of stress.Among them,the intra-aggregate pore volume with pore size less than the dominant pore size increases more obviously.

关 键 词：黄泛区粉土 孔隙特征 扫描电镜 核磁共振 集聚体 

分 类 号：TU411.92[建筑科学—岩土工程]