Geomechanics and Engineering

Techno-Press (테크노프레스)
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Free-strain solutions for two-dimensional consolidation with sand blankets under multi-ramp loading

  • Zan Li (Institute of Geotechnical Engineering, Southeast University) ;
  • Songyu Liu (Institute of Geotechnical Engineering, Southeast University) ;
  • Cuiwei Fu (China Railway First Survey and Design Institute Group Co., Ltd.)
  • Received : 2022.07.29
  • Accepted : 2023.11.01
  • Published : 2023.11.25
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Abstract

To analyze the consolidation with horizontal sand drains, the plane strain consolidation model under multi-ramp loading is established, and its corresponding analytical solution is derived by using the separation of variables method. The proposed solution is verified by the field measurement data and finite element results. Then, the effects of the loading mode and stress distribution on consolidation and dissipation of pore pressure are investigated. At the same time, the influence of hydraulic conductivity and thickness of sand blankets on soil consolidation are also analyzed. The results show that the loading mode has a significant effect on both the soil consolidation rate and generation-dissipation process of pore water pressure. In contrast, the influence of stress distribution on pore pressure dissipation is obvious, while its influence on soil consolidation rate is negligible. To guarantee the fully drained condition of the sand blanket, the ratio of hydraulic conductivity of the sand blanket to that of clay layer kd/kv should range from 1.0×104 to 1.0×106 with soil width varying from 100 m to 1000 m. A larger soil width correspondingly needs a greater value of kd/kv to make sure that the pore water can flow through the sand blanket smoothly with little resistance. When the soil width is relatively small (e.g., less than 100 m), the effect of thickness of the sand blanket on soil consolidation is insignificant. And its influence appears obvious gradually with the increase of the soil width.

Keywords

Acknowledgement

The research was financially supported by the National Natural Science Foundation of China (Grant No. 41972269), and the Jiangsu Provincial Transportation Engineering Construction Bureau (CX-2019GC02).

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