Recent research and development of ground column technologies

Han, Jie

doi:10.1680/grim.13.00016

Cited by 75 publications

(19 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Whichever be the case, such soils are considered unsuitable for pavement construction (Winter and Wong, 2020). In places where they are encountered as the natural soils, they are either removed and substituted with a borrowed subgrade material or improved by addition of some stabilising materials (Han, 2014).…”

Section: Introductionmentioning

confidence: 99%

Effect of Untreated Oil Palm Fruit Fibre on the Engineering Properties of Road Construction Earth Materials

Nwakaire¹,

Evaristus²,

Elijah³

2020

Preprint

View full text Add to dashboard Cite

This study first evaluated the engineering properties of lateritic soil samples from three selected locations in South Eastern Nigeria (Nawfia, Okpuno, and Ugwuoba). The effect of Oil Palm Fruit Fibre (OPFF) on the properties of these soil materials was investigated, with special emphasis on road construction applicability. The samples were subjected to different tests to ascertain their index properties. Varying proportions of OPFF from 0.5% to 3% were incorporated into the soil samples and the effects were observed based on compaction and California Bearing Ratio (CBR) results. The control samples without inclusion of OPFF achieved the highest Maximum Dry Densities (MDD), the MDDs reduced linearly as the OPFF content increased. Consequently, the CBR values decreased with increase in OPFF. The reduction in MDD for the Nawfia samples ranged from 0.29% to 5.31% as the OPFF increased from 0.5% to 3%. The MDD of the Okpuno sample also reduced within the range of 1.25% to 9.51% whereas the reduction for the Ugwuoba soil is within the range of 1.55% and 9.79%. With the inclusion of the OPFF, there was up to 75% to 83% drop in CBR values of the soil rendering them very unsuitable for pavement subgrade. It was concluded that the presence of fibre depreciated the engineering properties of the earth materials. Direct application of OPFF in any part of road pavement has been dissuaded.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of Untreated Oil Palm Fruit Fibre on the Engineering Properties of Road Construction Earth Materials

Nwakaire¹,

Evaristus²,

Elijah³

2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Rigid or semi-rigid inclusions (e.g., adding lime or cement) is another common alternative (e.g., [ 6 , 7 ]). Han [ 8 ] summarizes different ground column technologies.…”

Section: Introductionmentioning

confidence: 99%

Modeling Stone Columns

Castro

2017

Materials

View full text Add to dashboard Cite

This paper reviews the main modeling techniques for stone columns, both ordinary stone columns and geosynthetic-encased stone columns. The paper tries to encompass the more recent advances and recommendations in the topic. Regarding the geometrical model, the main options are the “unit cell”, longitudinal gravel trenches in plane strain conditions, cylindrical rings of gravel in axial symmetry conditions, equivalent homogeneous soil with improved properties and three-dimensional models, either a full three-dimensional model or just a three-dimensional row or slice of columns. Some guidelines for obtaining these simplified geometrical models are provided and the particular case of groups of columns under footings is also analyzed. For the latter case, there is a column critical length that is around twice the footing width for non-encased columns in a homogeneous soft soil. In the literature, the column critical length is sometimes given as a function of the column length, which leads to some disparities in its value. Here it is shown that the column critical length mainly depends on the footing dimensions. Some other features related with column modeling are also briefly presented, such as the influence of column installation. Finally, some guidance and recommendations are provided on parameter selection for the study of stone columns.

show abstract

“…Construction time and time to settlement stabilisation are also important challenges to construction over soft foundations. Certain techniques must be used to improve the soil foundation to enhance the stability of the embankment and eliminate the problems associated with bearing failure and settlement (Han and Gabr 2002;Jenck et al 2007;Han 2015b). Possible techniques include surface and deep compaction and densification, over-excavation and replacement, deep replacement, preloading and consolidation, and chemical stabilisation (Han 2015a).…”

Section: Introductionmentioning

confidence: 99%

“…Possible techniques include surface and deep compaction and densification, over-excavation and replacement, deep replacement, preloading and consolidation, and chemical stabilisation (Han 2015a). However, granular columns (including geosyntheticencased granular columns), deep mixed columns, and piles have been more commonly used to support embankments over soft soils (Han 2015a(Han , 2015b. When approaching embankments are used to connect bridges or new embankments are constructed to widen existing embankments, there is a strict requirement for total and differential settlements on top of the embankment (often less than 25 mm) (Han et al 2007;El Kamash and Han 2014).…”

Section: Introductionmentioning

confidence: 99%

Scaled model tests on influence factors of full geosynthetic-reinforced pile-supported embankments

Song

Han

2016

Geosynthetics International

View full text Add to dashboard Cite

A geosynthetic-reinforced pile-supported (GRPS) embankment that consists of embankment fill, geosynthetic, piles, and foundation soils is a complex soil-structure system. Its key load transfer mechanisms include soil arching and tensioned membrane effects and subsoil resistance. Type of embankment fill (cohesive or cohesionless) and type of pile (end-bearing or floating) are expected to affect these load transfer mechanisms; however, their influence has not been well investigated. Six scaled model tests were conducted in this study to investigate the influence of the embankment fill properties, the clear spacing of pile caps, and the pile type on soil arching and tensioned membrane effects. This study used cohesive and cohesionless embankment fills and end-bearing and floating piles. The test results show that the cohesive embankment fill strengthened the soil-arching effect, increased the pile efficacy, and reduced the settlements of the subsoil between pile caps and the embankment crest under the same load as compared with the cohesionless embankment fill. The soil arching-effect was inversely proportional to the clear spacing of pile caps. Soil arching initiated at a low ratio of the embankment height to the clear spacing of pile caps (i.e. 0.5 to 0.7) and became stable at a higher ratio (i.e. 1.1 to 1.5). The embankment height when the soil arching becomes stable is also referred to as the critical height, at which full soil arching is formed. The measured vertical earth pressures at the edges of the pile caps were higher than those in the middle of the pile caps in all six model tests. When the end-bearing or floating piles were used, the loads on the piles (i.e. the pile efficacy) increased during the construction of the embankment. However, when the floating piles started to penetrate into the underlying soil under a higher load; the pile efficacy decreased with the embankment and the surcharge load. Floating piles resulted in less soil arching and larger settlement.

show abstract

Recent research and development of ground column technologies

Cited by 75 publications

References 58 publications

Effect of Untreated Oil Palm Fruit Fibre on the Engineering Properties of Road Construction Earth Materials

Effect of Untreated Oil Palm Fruit Fibre on the Engineering Properties of Road Construction Earth Materials

Modeling Stone Columns

Scaled model tests on influence factors of full geosynthetic-reinforced pile-supported embankments

Contact Info

Product

Resources

About