Equivalent plane strain modeling of vertical drains in soft ground under embankment combined with vacuum preloading

2008 ◽  
Vol 35 (5) ◽  
pp. 655-672 ◽  
Author(s):  
Tuan Anh Tran ◽  
Toshiyuki Mitachi
Keyword(s):  
Plane Strain ◽  
Soft Ground ◽  
Vacuum Preloading ◽  
Vertical Drains ◽  
Strain Modeling

scholarly journals Analytical and numerical solutions for a single vertical drain including the effects of vacuum preloading

2005 ◽  
Vol 42 (4) ◽  
pp. 994-1014 ◽  
Author(s):  
Buddhima Indraratna ◽  
Cholachat Rujikiatkamjorn ◽  
Iyathurai Sathananthan
Keyword(s):  
Finite Element ◽  
Plane Strain ◽  
Numerical Solutions ◽  
Soft Clay ◽  
Vacuum Pressure ◽  
Excess Pore Pressure ◽  
Soil Consolidation ◽  
Vacuum Preloading ◽  
Element Analysis ◽  
Vertical Drains

A system of vertical drains combined with vacuum preloading is an effective method to accelerate soil consolidation by promoting radial flow. This study presents the analytical modeling of vertical drains incorporating vacuum preloading in both axisymmetric and plane strain conditions. The effectiveness of the applied vacuum pressure along the drain length is considered. The exact solutions applied on the basis of the unit cell theory are supported by finite element analysis using ABAQUS software. Subsequently, the details of an appropriate matching procedure by transforming permeability and vacuum pressure between axisymmetric and equivalent plane strain conditions are described through analytical and numerical schemes. The effects of the magnitude and distribution of vacuum pressure on soft clay consolidation are examined through average excess pore pressure, consolidation settlement, and time analyses. Lastly, the practical implications of this study are discussed.Key words: consolidation, finite element method, soft clay, vacuum preloading, vertical drains.

scholarly journals Plane-Strain Modeling of Smear Effects Associated with Vertical Drains

1999 ◽  
Vol 125 (1) ◽  
pp. 96-99 ◽  
Author(s):  
Richard E. Landau ◽  
D. Russell ◽  
C. C. Hird ◽  
I. C. Pyrah ◽  
B. Indraratna ◽  
...  
Keyword(s):  
Plane Strain ◽  
Vertical Drains ◽  
Strain Modeling

Modelling the effect of vertical drains in two-dimensional finite element analyses of embankments on soft ground

1995 ◽  
Vol 32 (5) ◽  
pp. 795-807 ◽  
Author(s):  
C.C. Hird ◽  
I.C. Pyrah ◽  
D. Russell ◽  
F. Cinicioglu
Keyword(s):  
Finite Element ◽  
Plane Strain ◽  
Unit Cell ◽  
Lateral Strain ◽  
Soft Ground ◽  
Two Dimensional ◽  
Finite Element Analyses ◽  
Case Histories ◽  
Vertical Drains ◽  
Dimensional Finite Element

A recently developed method for modelling the effect of vertical drains in plane strain finite element analyses of consolidation beneath embankments on soft ground is applied to three case histories. Analyses are reported for the consolidation of the soil served by a single drain (a unit cell) under conditions of no lateral strain. In all three cases a good match was obtained between the average degrees of consolidation in an axisymmetric unit cell and the equivalent plane strain unit cell. This suggests that the method could be used to facilitate full two-dimensional analyses of many embankments. The results of the analyses are also compared with the available field data. Key words : vertical drains, consolidation, finite elements, embankments.

Influence of Bending of Plastic Vertical Drain on Consolidation via Vacuum Preloading

2014 ◽  
Vol 644-650 ◽  
pp. 4826-4830
Author(s):  
Bin Bin Xu ◽  
Shotaro Yamada ◽  
Toshihiro Noda
Keyword(s):  
Ground Improvement ◽  
Ground Surface ◽  
Soft Ground ◽  
Finite Element Analyses ◽  
Vacuum Preloading ◽  
Vertical Drains ◽  
Bending Effect ◽  
Vertical Drain ◽  
Drainage Capacity ◽  
Soft Ground Improvement

The soft ground improvement employing vacuum preloading is widely used in Tianjin. In the application of vacuum preloading, the bending of plastic vertical drains (PVDs) often occurs accompanying the large settlement of the soft ground or the significant shear strain at the ground surface. In order to investigate the influence of bending of PVDs on the ground consolidation, three different bending shapes of PVDs are assumed and a series soil-water coupled finite element analyses are carried out. It is found that: 1) the macro-element method is available to take the bending effect of PVDs into consideration; 2) the bending at the bottom of PVDs has much impact on the consolidation of ground even though the hydraulic gradient at the bottom is much smaller than that at the top; 3) Due to the bending of PVDs at the bottom the drainage capacity is much influenced and the volumetric compression only occurs at the first few layers of the ground.

scholarly journals Applying the Equivalent Plane Strain solution to design the soft soil improvement by vertical drains

2020 ◽  
Vol 61 (3) ◽  
pp. 28-37
Author(s):  
Nu Thi Nguyen ◽  
Keyword(s):  
Plane Strain ◽  
Permeability Coefficient ◽  
Soft Soil ◽  
Soil Improvement ◽  
Field Monitoring ◽  
Soft Ground ◽  
Vertical Drains ◽  
Equivalent Permeability ◽  
Ground Treatment ◽  
Treatment Design

The soft soil improvement by vertical drains (PVD, sand drains) are widely used in Vietnam. One of the methods is used for designing soft soil improvement by vertical drains is the Equivalent Plane Strain solution. To use this solution, the permeability coefficient of soil is converted into the equivalent permeability under plane strain. The paper presents the application of this solution to design soft soil improvement by sand drains at Km 3+130 Vi Thanh - Can Tho. It indicated that the settlement results of the soft ground treatment design based on Equivalent Plane Strain solution are similar to those from the Axisymmetric Condition analysis and field monitoring.

scholarly journals Numerical Investigation to the Effect of Suction-Induced Seepage on the Settlement in the Underwater Vacuum Preloading with Prefabricated Vertical Drains

2021 ◽  
Vol 9 (8) ◽  
pp. 797
Author(s):  
Shu Lin ◽  
Dengfeng Fu ◽  
Zefeng Zhou ◽  
Yue Yan ◽  
Shuwang Yan
Keyword(s):  
Practical Implication ◽  
Soil Surface ◽  
Small Strain ◽  
Seepage Flow ◽  
Excess Pore Pressure ◽  
Combined Effects ◽  
Vacuum Preloading ◽  
Prefabricated Vertical Drains ◽  
Vertical Drains ◽  
The Difference

Vacuum preloading combined with prefabricated vertical drains (PVDs) has the potential to improve the soft sediments under water, however, its development is partly limited by the unclear understanding of the mechanism. This paper aims to extend the comprehension of the influential mechanism of overlapping water in the scenario of underwater vacuum preloading with PVDs. The systematic investigations were conducted by small strain finite element drained analyses, with the separated analysis schemes considering suction-induced consolidation, seepage and their combination. The development of settlement in the improved soil region and the evolution of seepage flow from the overlapping water through the non-improved soil region into improved zone are examined in terms of the build-up of excess pore pressure. Based on the results of numerical analyses, a theoretical approach was set out. It was capable to estimate the time-dependent non-uniform settlement along the improved soil surface in response to the combined effects of suction-induced consolidation and seepage. The difference of underwater and onshore vacuum preloading with PVDs is discussed with some practical implication and suggestion provided.

Sign in / Sign up

Export Citation Format

Share Document