›› 2018, Vol. 39 ›› Issue (3): 933-942.doi: 10.16285/j.rsm.2016.0659

• 基础理论与实验研究 • 上一篇    下一篇

结构性砂土静力触探试验离散元分析

刘 笋1,蒋明镜1, 2, 3, 4,付 昌2, 3,朱俊高1   

  1. 1. 河海大学 岩土工程科学研究所,江苏 南京 210098;2. 同济大学 地下建筑与工程系,上海 200092; 3. 同济大学 岩土及地下工程教育部重点实验室,上海 200092;4. 同济大学 土木工程防灾国家重点实验室,上海 200092
  • 收稿日期:2016-04-05 出版日期:2018-03-12 发布日期:2018-06-06
  • 通讯作者: 蒋明镜,男,1965年生,教授,博士生导师,主要从事天然结构性黏土、砂土、非饱和土、太空土和深海能源土宏微观试验、本构模型和数值分析研究。E-mail: mingjing.jiang@tongji.edu.cn E-mail:liusunx@126.com
  • 作者简介:刘笋,男,1991年生,硕士,主要从事离散元数值模拟方面的研究工作。
  • 基金资助:

    国家自然科学基金项目(No.51579178);防灾国家重点实验室项目(No.300 SLDRCE14-A-04)

Distinct element analysis of cone penetration tests in structured sand ground

LIU Sun1, JIANG Ming-jing1, 2, 3, 4, FU Chang2, 3, ZHU Jun-gao1   

  1. 1. Geotechnical Research Institute, Hohai University, Nanjing, Jiangsu 210098, China; 2. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China; 3. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai 200092, China; 4. State Key Laboratory Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China
  • Received:2016-04-05 Online:2018-03-12 Published:2018-06-06
  • Supported by:

    This work was supported by the National Science Foundation of China (51579178) and the State Key Lab. of Disaster Reduction in Civil Engineering (300 SLDRCE14-A-04).

摘要: 为研究结构性砂土静力触探的宏微观力学特性,在10 g重力场中生成一个净砂地基;将一个考虑胶结厚度的微观胶结接触模型引入到净砂地基中以生成结构性砂土地基;用一定速率移动探杆以模拟结构性砂土中的静力触探过程,其中,探杆由4面刚性墙组成。结果表明,随着贯入深度的增加,锥尖贯入阻力逐渐增大,增长速度逐渐减慢,在达到临界深度后贯入阻力在某一定值附近波动;锥尖部位有明显的力链集中现象,力链的集中程度和范围会随着贯入深度的增加而逐渐提高和扩大;静力触探过程中,探杆两侧的土体经历了明显的加载和卸载过程,且土体主应力方向发生偏转;离探杆越远,主应力偏转速度越慢,最终偏转角越小;不同深度处平均纯转动率(APR)的变化趋势基本相同,而APR最大值会随着土体深度而逐渐增加;探杆的贯入会使土颗粒间胶结发生破坏,胶结的破坏形式主要有拉剪破坏和压剪破坏两种,而拉剪破坏数目要比压剪破坏数目多。

关键词: 静力触探试验, 结构性砂土, 离散单元法, 宏、微观力学特性

Abstract: To study macro and micro mechanical properties of cone penetration tests in structured sand, a pure sand ground was prepared firstly under 10 g condition. Then, a bond contact model considering bond thickness was implemented into the pure sand ground to prepare the structured sand ground. A penetrometer composed of four sides of rigid walls was moving downward to simulate cone penetration tests in structured sand ground. The results showed that with the increase of penetration depth, the tip resistance increased gradually but the growth rate slowed down step by step. When the tip reached the critical depth, the tip resistance began fluctuating around a certain value. The contact force chain around the tip is very concentrated. With the increasing penetration depth, the concentrative degree of contact force chain increased gradually and the concentration range of contact force chain expanded gradually. In the process of penetration, the soil around the penetrometer underwent a significant loading and unloading process, and the principal stress direction took rotation. The farther away from the penetrometer, the slower rotation speed of the principal stress, and the smaller the final rotation angle. The averaged pure rotation rate (APR) at different depths changed in a qualitatively identical way, but the APR maximum values increased gradually with the depth of soil. The cone penetration breaks the bond between the soil particles. There are two main kinds of bond failure modes, tension-shear breakage and compression-shear breakage, and the number of tensile-shear breakage is much more than that of compression-shear breakage.

Key words: cone penetration tests, structured sand, distinct element method, macro and micro mechanical properties

中图分类号: 

  • TU 441

[1] 杨济铭, 张小勇, 张福友, 曾超峰, 梅国雄, . 砂土中桩-土-承台协同作用下桩基 承载特性细观研究[J]. 岩土力学, 2020, 41(7): 2271-2282.
[2] 毛浩宇, 徐奴文, 李彪, 樊义林, 吴家耀, 孟国涛, . 基于离散元模拟和微震监测的白鹤滩水电站左岸地下厂房稳定性分析[J]. 岩土力学, 2020, 41(7): 2470-2484.
[3] 旷杜敏, 龙志林, 周益春, 闫超萍, 陈佳敏, . 基于BP神经网络的岩土胶结材料速率敏感 效应预测研究[J]. 岩土力学, 2019, 40(S1): 390-399.
[4] 张成功, 尹振宇, 吴则祥, 金银富, . 颗粒形状对粒状材料圆柱塌落影响的 三维离散元模拟 [J]. 岩土力学, 2019, 40(3): 1197-1203.
[5] 景 路, 郭颂怡, 赵 涛, . 基于流体动力学-离散单元耦合算法的 海底滑坡动力学分析[J]. 岩土力学, 2019, 40(1): 388-394.
[6] 刘勋楠,赵兰浩,毛 佳,许 栋,. 三维距离势离散单元法[J]. , 2018, 39(7): 2639-2650.
[7] 周兴涛,盛 谦,崔 臻,冷先伦,付晓东,马亚丽娜, . 颗粒离散单元法动力人工边界设置方法[J]. , 2018, 39(7): 2671-2680.
[8] 崔 臻,盛 谦,冷先伦,罗庆姿,. 地下洞室地震动力响应的岩体结构控制效应[J]. , 2018, 39(5): 1811-1824.
[9] 李 磊,蒋明镜,张伏光, . 深部岩石考虑残余强度时三轴试验离散元定量模拟及参数分析[J]. , 2018, 39(3): 1082-1090.
[10] 罗 滔,E. T. Ooi,A. H. C Chan,傅少君,. 一种模拟堆石料颗粒破碎的离散元-比例边界有限元结合法[J]. , 2017, 38(5): 1463-1471.
[11] 张 徐,赵春发,翟婉明,冯 洋. 铁路有砟道床振动和变形的离散元模拟与试验验证[J]. , 2017, 38(5): 1481-1488.
[12] 王志超,李大鸣,. 基于SPH-DEM流-固耦合算法的滑坡涌浪模拟[J]. , 2017, 38(4): 1226-1232.
[13] 罗 滔,OOI E T,CHAN A H C,傅少君,. 一种模拟堆石料的二维多边形离散单元法及程序[J]. , 2017, 38(3): 883-892.
[14] 董 林,王兰民,夏 坤,袁晓铭,. 基于台湾集集地震数据的CPT与SPT液化判别方法比较[J]. , 2017, 38(12): 3643-3648.
[15] 田 密,李典庆,曹子君,方国光,王 宇,. 基于贝叶斯理论的土性参数空间变异性量化方法[J]. , 2017, 38(11): 3355-3362.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!