砂土地基强夯室内模型试验及加固特性分析
DOI:
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

TU472.3

基金项目:

滨海软土地基电渗-强夯法联合加固机理研究;河湖库塘淤泥电渗-强夯联合处置及资源化利用技术研究


Laboratory model test and reinforcement characteristics analysis on dynamic compaction of sand foundation
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    为了获取德国莱比锡砂土地基强夯加固特性,采用自行设计的模型试验装置及量测系统,制备3种相对密实度的砂土进行了强夯室内模型试验,每组试验进行24击强夯。强夯过程中测量夯锤速度、位移、动态力、能量释放时间变化,结合PIV (particle image velocimetry)技术分析强夯后砂土颗粒位移结果,得到水平方向和深度方向的有效加固范围发展特性。结果表明:第6、12、18、24击的速度时程曲线在快速下降阶段基本重合,击数越高回弹速度越高、持续时间越短,体现为能量释放时间的不同;对于ID0.4、ID0.5、ID0.7试验组,从第6击到第24击的强夯能量释放时间分别下降38.9%、34.7%、31.4%,在第24击的夯锤位移回弹比分别达到65.3%、67.1%、69.0%;砂土相对密实度越高,夯锤冲击力越大,第6、12、18、24击之间的差别越小;随着夯击次数的增加,夯锤动态力峰值逐渐提高、上行曲线斜率变小,冲击行程逐渐缩短;ID0.4、ID0.5、ID0.7试验组分别在第20、18、15击后,水平方向有效加固范围增长大于深度方向。

    Abstract:

    In order to obtain the dynamic compaction characteristics of Leipzig sandy soil foundation in Germany, a self-designed model test device and measurement system were adopted. Three different relative density of sand were prepared for dynamic compaction in the laboratory model tests, each group of test was carried out with 24 tamping times. During the dynamic compaction, the velocity, displacement, dynamic force and energy release duration of tampings were measured. PIV (particle image velocimetry) technology was adopted to investigate the sand particles displacement after the dynamic compaction, and the development characteristics of effective reinforcement area in horizontal direction and depth direction were obtained. The results show that the velocity-time curves of the 6th, 12th, 18th and 24th tampings are basically coincidence with each others in the rapid declining stage. When the higher tamping times achieved, the rebound velocity will be higher with shorter duration, which reflecting the different energy release duration. For ID0.4, ID0.5, and ID0.7, the energy release duration decreases by 38.9%, 34.7% and 31.4%, respectively, from the 6th to the 24th tampings; while the resilience ratio of the tamp in the 24th tamping reaches to 65.3%, 67.1% and 69.0%, respectively. The higher the relative density of the sand, the greater the impact force of tamp, and the smaller the differences between the 6th, 12th, 18th and 24th tampings. With the increase of the tamping times, the peak value of dynamic force gradually increases, the slope of upward curves become smaller, and the impact duration are gradually shorter. For ID0.4, ID0.5 and ID0.7, after the 20th, 18th and 15th tampings, respectively, the effective reinforcement area in horizontal direction increases more than in depth direction.

    参考文献
    相似文献
    引证文献
引用本文

王锃,郑凌逶,罗嗣海,等. 砂土地基强夯室内模型试验及加固特性分析[J]. 科学技术与工程, 2020, 20(18): 7394-7400.
Wang Zeng, Zheng Lingwei, Luo Sihai, et al. Laboratory model test and reinforcement characteristics analysis on dynamic compaction of sand foundation[J]. Science Technology and Engineering,2020,20(18):7394-7400.

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2020-01-12
  • 最后修改日期:2020-05-08
  • 录用日期:2020-02-21
  • 在线发布日期: 2020-07-28
  • 出版日期:
×
律回春渐,新元肇启|《科学技术与工程》编辑部恭祝新岁!
亟待确认版面费归属稿件,敬请作者关注