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Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Numerical study on load transfer effect of Stiffened Deep Mixed column-supported embankment over soft soil
Abstract A new composite column technique referred to as Stiffened Deep Mixed (SDM) column has been adopted to support embankment over soft soil to mitigate the post-construction settlement, increase bearing capacity and enhance stability. The SDM column was formed by inserting a precast concrete core pile into the center of a Deep Mixed (DM) column immediately after the construction of DM column. Due to the complicate interaction between concrete core pile, DM column and surrounding soil, the load transfer mechanism between SDM column and surrounding soil has not been well understood yet. This paper presents a series of three- Dimensional (3-D) finite-element analyses to investigate the load transfer effect of SDM column-reinforced ground under embankment. First, the numerical method was validated by a comparison with field data in terms of settlements and vertical stress on the head of SDM column. Then, based on the validated simulation method, the 3-D numerical model of the SDM column-supported embankment over soft soil was established, and the influence factors of length of DM column and concrete core pile, cross section area of concrete core pile, column spacing and embankment height on the load transfer effect were investigated, respectively. The results showed that the column spacing and height of embankment fill had significant effects on the load transfer between SDM column and surrounding soil, while the influences of length of DM column and concrete core pile, and cross section area of concrete core pile on the load transfer effect were minor. Finally, four current commonly-used design methods were assessed in the prediction of the efficacy of SDM-reinforced soil under embankment loading. The current commonly-used design methods showed great differences in the load transfer predictions of the SDM column-supported embankment over soft soil due to the existence of outer DM column socket. A modified method was proposed for the use of EBGEO (2011) in the design of SDM column-supported embankment over soft soil.
Numerical study on load transfer effect of Stiffened Deep Mixed column-supported embankment over soft soil
Abstract A new composite column technique referred to as Stiffened Deep Mixed (SDM) column has been adopted to support embankment over soft soil to mitigate the post-construction settlement, increase bearing capacity and enhance stability. The SDM column was formed by inserting a precast concrete core pile into the center of a Deep Mixed (DM) column immediately after the construction of DM column. Due to the complicate interaction between concrete core pile, DM column and surrounding soil, the load transfer mechanism between SDM column and surrounding soil has not been well understood yet. This paper presents a series of three- Dimensional (3-D) finite-element analyses to investigate the load transfer effect of SDM column-reinforced ground under embankment. First, the numerical method was validated by a comparison with field data in terms of settlements and vertical stress on the head of SDM column. Then, based on the validated simulation method, the 3-D numerical model of the SDM column-supported embankment over soft soil was established, and the influence factors of length of DM column and concrete core pile, cross section area of concrete core pile, column spacing and embankment height on the load transfer effect were investigated, respectively. The results showed that the column spacing and height of embankment fill had significant effects on the load transfer between SDM column and surrounding soil, while the influences of length of DM column and concrete core pile, and cross section area of concrete core pile on the load transfer effect were minor. Finally, four current commonly-used design methods were assessed in the prediction of the efficacy of SDM-reinforced soil under embankment loading. The current commonly-used design methods showed great differences in the load transfer predictions of the SDM column-supported embankment over soft soil due to the existence of outer DM column socket. A modified method was proposed for the use of EBGEO (2011) in the design of SDM column-supported embankment over soft soil.
Numerical study on load transfer effect of Stiffened Deep Mixed column-supported embankment over soft soil
Ye, Guanbao (Autor:in) / Cai, Yongsheng (Autor:in) / Zhang, Zhen (Autor:in)
KSCE Journal of Civil Engineering ; 21 ; 703-714
10.06.2016
12 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Numerical Investigation of T-Shaped Soil-Cement Column Supported Embankment Over Soft Ground
| Springer Verlag | 2018