# [1]于光明,龚维明,戴国亮,等.考虑固结流变的软土地基单桩下拉荷载计算[J].东南大学学报(自然科学版),2020,50(4):606-615.[doi:10.3969/j.issn.1001-0505.2020.04.002] 　Yu Guangming,Gong Weiming,Dai Guoliang,et al.Calculation of dragload of single pile in soft soil considering consolidation and rheology[J].Journal of Southeast University (Natural Science Edition),2020,50(4):606-615.[doi:10.3969/j.issn.1001-0505.2020.04.002] 点击复制 考虑固结流变的软土地基单桩下拉荷载计算() 分享到： var jiathis_config = { data_track_clickback: true };

50

2020年第4期

606-615

2020-07-20

## 文章信息/Info

Title:
Calculation of dragload of single pile in soft soil considering consolidation and rheology

Author(s):
Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education, Southeast University, Nanjing 211189, China
School of Civil Engineering, Southeast University, Nanjing 211189, China

Keywords:

TU473
DOI:
10.3969/j.issn.1001-0505.2020.04.002

Abstract:
To study the calculation method of dragload of the single pile in soft soil under large-area loading, the rheological model of soft soil is introduced based on the non-Darcy flow law. A nonlinear calculation model for the long-term settlement of large deformation of the soft soil foundation is established by considering the combination of the consolidation and rheology in Lagrangian coordinates. The model considers that the void ratio and the permeability coefficient change with the discharge of pore water during the consolidation rheology. Based on the load transfer method, the time effect of the interface shear strength is studied during the interaction between the pile and the soil in the consolidated rheological soil. The theoretical calculation method of dragload of the single pile is proposed by considering the coupling effect of the non-Darcy flow consolidation and rheology of soft soil under large-area surcharge. The long-term variation law of the dragload distribution and neutral point’s position of the pile is obtained by assuming the deformation of the pile top to carry out an iterative solution. Finally, the proposed method is compared with the traditional consolidation calculation method, and the effects of average consolidation degree, non-Darcy consolidation parameters, rheological parameters and surcharge on the dragload are analyzed. The results show that the calculation results based on the traditional soil consolidation theory are conservative, and it is necessary to consider the adverse effect of the consolidation rheology on the bearing capacity of single pile.

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