Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 9 of 9
Full-Text Articles in Engineering
Current State Of The Art In Vacuum Preloading For Stabilising Soft Soil, Cholachat Rujikiatkamjorn, Buddhima Indraratna
Current State Of The Art In Vacuum Preloading For Stabilising Soft Soil, Cholachat Rujikiatkamjorn, Buddhima Indraratna
Buddhima Indraratna
In this paper the analytical solutions for radial consolidation that include time dependent surcharge loading and vacuum pressure are proposed, whilst also considering the impact of the parabolic variation of permeability in the smear zone. The use of the spectral method for multilayered soil consolidation is introduced and verified. The Elliptical Cavity Expansion Theory is used to predict the extent of soil disturbance (smear zone) caused by the installation of mandrel driven vertical drains. The predicted smear zone is then compared to the data obtained from large-scale radial consolidation tests. Furthermore, the advantages and limitations of applying a vacuum through …
3d Numerical Modelling Of Hexagonal Wire Mesh Reinforced Embankment On Soft Bangkok Clay, Cholachat Rujikiatkamjorn, Buddhima Indraratna, Dennes T. Bergado
3d Numerical Modelling Of Hexagonal Wire Mesh Reinforced Embankment On Soft Bangkok Clay, Cholachat Rujikiatkamjorn, Buddhima Indraratna, Dennes T. Bergado
Buddhima Indraratna
The numerical modeling of the full scale test embankment reinforced with hexagonal wire mesh was analyzed using finite difference method under three dimensional (3D) conditions to reflect the actual embankment dimensions. In the analysis, the 3D finite difference simulation using 5 times of vertical laboratory permeability can reasonably predict its behavior on soft foundation. In comparison with the field measurements, the predicted results from 3D analysis reasonably agreed with measured data including vertical settlement, excess pore pressures and lateral displacements. Thus, the actual embankment geometry and the selected permeability influenced the behavior of the reinforced embankment constructed on soft ground …
Numerical Solution Of Stone Column Improved Soft Soil Considering Arching, Clogging And Smear Effects, Buddhima Indraratna, Sudip Basack, Cholachat Rujikiatkamjorn
Numerical Solution Of Stone Column Improved Soft Soil Considering Arching, Clogging And Smear Effects, Buddhima Indraratna, Sudip Basack, Cholachat Rujikiatkamjorn
Buddhima Indraratna
Improvement of soft clay deposits by the installation of stone columns is one of the most popular techniques followed worldwide. The stone columns not only act as reinforcingmaterial increasing the overall strength and stiffness of the compressible soft soil, but they also promote consolidation through effective drainage. The analytical and numerical solutions available for ascertaining the response of column-reinforced soil have been developed on the basis of the equal strain hypothesis. For typical surcharge (embankment) loading, the free strain analysis appears to give more realistic results comparable to field data. The paper presents a novel numericalmodel (finite-differencemethod) to analyze the …
Cyclic Behaviour Of Soft Soil Subgrade Improved By Prefabricated Vertical Drains, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Jing Ni
Cyclic Behaviour Of Soft Soil Subgrade Improved By Prefabricated Vertical Drains, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Jing Ni
Buddhima Indraratna
The behaviour of saturated soft clays subjected to cyclic loading is of considerable importance in the design of railway subgrades. Soft clays can be extensively found in many coastal regions of Australia up to significant depths, including the coastal belt and the central part of NSW. These soft clay deposits are characterised by very low bearing capacity and excessive settlement. The increase in generated excess pore pressures due to heavy freight trains significantly reduces the bearing capacity and causes serious damage to the rail infrastructure such as clay pumping underneath railway tracks and excessive subsidence. The use of prefabricated vertical …
Non-Linear Analysis Of Soft Ground Consolidation At The Ballina By-Pass, Xueyu Geng, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Richard Kelly
Non-Linear Analysis Of Soft Ground Consolidation At The Ballina By-Pass, Xueyu Geng, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Richard Kelly
Buddhima Indraratna
This study presents a numerical assessment of consolidation under vacuum preloading with a system of vertical drains and membrane, considering the non-linear properties of the soil This membrane system, already widely used in Australia, is where an airtight membrane is placed over the drainage layer to allow a vacuum to be distributed within the sand platform, along the surface of the soil, and down the vertical drains. To date, there have only been a few fundamental investigations and field studies that have tried to assess the way in which the vacuum can propagate in soft clay, both laterally and vertically. …
Predicted And Observed Behaviour Of Soft Clay Foundations Stabilised With Vertical Drains, Buddhima Indraratna, Wadud Salim, I W Redana
Predicted And Observed Behaviour Of Soft Clay Foundations Stabilised With Vertical Drains, Buddhima Indraratna, Wadud Salim, I W Redana
Buddhima Indraratna
A novel plane strain approach is introduced to model the behaviour of embankment foundations on soft clay stabilised with vertical drains, where the classical axisymmetric solutions are converted to an equivalent plane strain model, incorporating the effects of smear and well resistance. This paper describes the behaviour of an embankment stabilised with vertical drains, where a specific case history is selected from Malaysia. The consolidation of soft clay is modelled on the basis of the modified Cam-clay. The settlement behaviour at various stages of embankment loading is analysed using the finite element technique, and the numerical results are compared with …
Soft Soils Improved By Prefabricated Vertical Drains: Performance And Prediction, Buddhima Indraratna, Cholachat Rujikiatkamjorn, V Wijeyakulasuriya, G Mcintosh, R Kelly
Soft Soils Improved By Prefabricated Vertical Drains: Performance And Prediction, Buddhima Indraratna, Cholachat Rujikiatkamjorn, V Wijeyakulasuriya, G Mcintosh, R Kelly
Buddhima Indraratna
The use of prefabricated vertical drains with preloading is now common practice and is proving to be one of the most effective ground improvement techniques known. The factors affecting its performance, such as the smear zone, the drain influence zone, and drain unsaturation, are discussed in this paper. In order to evaluate these effects a large scale consolidation test was conducted and it was found that the proposed Cavity Expansion Theory could be used to predict the characteristics of the smear zone based on the soil properties available. Moreover, the procedure for converting an equivalent 2-D plane strain multi-drain analysis …
A Study Of The Strength Of Lime Treated Soft Clays, Martin D. Liu, Stephen Pemberton, Buddhima Indraratna
A Study Of The Strength Of Lime Treated Soft Clays, Martin D. Liu, Stephen Pemberton, Buddhima Indraratna
Buddhima Indraratna
In this paper, a comprehensive study of the strength of lime treated soft clays is made. There are three major factors that affect the strength of the soils; they are the lime content, curing time, and curing temperature. The variations of soil strengths with the three factors are analysed and quantified via proposed empirical equations. These equations are verified against experimental data. Finally, a general strength criterion, unifying the influence of all the three factors into a single equation, is proposed. The capacity of the general equation is also demonstrated. It is seen that the proposed strength equations can provide …
Modelling Of Soft Ground Consolidation Via Combined Surcharge And Vacuum Preloading, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Ali Ghandeharioon
Modelling Of Soft Ground Consolidation Via Combined Surcharge And Vacuum Preloading, Buddhima Indraratna, Cholachat Rujikiatkamjorn, Ali Ghandeharioon
Buddhima Indraratna
A system of vertical drains combined with vacuum and surcharge preloading is an effective approach for promoting radial flow to accelerate soil consolidation. When a higher load is required to meet the desired rate of settlement and the cost of surcharge is also significant, the application of vacuum pressure with reduced surcharge loading can be used. The equivalent 2-D plane strain solution for multi-drain analysis is described with the inclusion of the effects of vacuum pressure and smear zone caused by mandrel driven vertical drains. A large-scale radial consolidometer is employed to determine the extent of the smear zone and …