One-Dimensional Compression Behavior of a Soil with High Organic Matter Content

Santagata, Marika; Bobet, Antonio; Johnston, Cliff T.; Hwang, Joonho

doi:10.1061/(asce)1090-0241(2008)134:1(1)

Cited by 59 publications

(33 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Peat is extremely compressible under loading, experiencing high initial rates of primary consolidation and substantial creep (Landva and La Rochelle, 1983;Santagata et al, 2008;Wong et al, 2009), with the creep component often greater than the primary consolidation (hydrodynamic) component (Farrell, 2012). In addition to the secondary compression component (i.e.…”

Section: Compressibility Characteristicsmentioning

confidence: 99%

“…In later stages, bacteria and fungi cause the transformation into humic substances (Hobbs, 1986;Tate, 1987), major classifications of which are humic acids, fulvic acids and humin. These are complex series of relatively high molecular weight yellow-black organic substances formed by secondary synthesis reactions (Santagata et al, 2008) and which are more recalcitrant to further decomposition.…”

Section: Effect Of Decomposition Process On Organic Mattermentioning

confidence: 99%

See 1 more Smart Citation

Effects of decomposition on the compressibility of fibrous peat — A review

O’Kelly¹,

Pichan²

2013

Geomechanics and Geoengineering

View full text Add to dashboard Cite

Peat deposits are comprised of high organic content substances primarily derived from dead plant vegetation. Peat itself is not inert but undergoes continuous biological decomposition that causes progressive destruction of the peat fabric, reductions in fibre and organic contents and biogas generation. Depending on the degree of decomposition, the organic solids can exist as fresh (intact) fibres, slightly decomposed or ultimately completely decomposed (amorphous) material. From a geotechnical perspective, an understanding of the relationship between degree of decomposition and engineering properties, including the level of compressibility, is important in dealing with such problematic deposits. However a review of the literature indicates that such relationships have not been sufficiently investigated. Moreover, potential impacts of uncontrolled or unexpected decomposition in-situ are regularly discounted in geotechnical practice. This paper reviews decomposition effects in peat and potentially significant knock-on effects in terms of the material's physical properties and compressibility. Progressive reduction in solids volume and deterioration in the integrity of the organic structure due to on-going decomposition may cause significant additional settlement to occur over time. More decomposed peat generally undergoes lower primary consolidation and creep strains and is also less prone to future decomposition, compared with lesser decomposed peat.

show abstract

Section: Compressibility Characteristicsmentioning

confidence: 99%

Section: Effect Of Decomposition Process On Organic Mattermentioning

confidence: 99%

Effects of decomposition on the compressibility of fibrous peat — A review

O’Kelly¹,

Pichan²

2013

Geomechanics and Geoengineering

View full text Add to dashboard Cite

show abstract

“…With an increase in p, cv decreased almost linearly and signiˆcantly, and theˆnal cv value was approximately 10 cm 2 /day. Past studies revealed that cv of normal consolidated peat decreases dramatically with an increase in p (e.g., Yamazoe and Mitachi, 2007;Santagata et al, 2008). In settlement calculation for clay, cv under the normal consolidated condition is usually assumed to be constant.…”

Section: Evaluation Of Consolidation Acceleration Ešectmentioning

confidence: 99%

Field Performance of PVD Combined with Reinforced Embankment on Peaty Ground

Hayashi

Nishimoto

Takahashi

2011

Soils and Foundations

View full text Add to dashboard Cite

This paper describes theˆeld performance of prefabricated vertical drains (PVD) used in combination with reinforced embankments on peaty ground. A large-scaleˆeld test of PVD adopted in combination with an embankment reinforced using galvanized steel grid was conducted on peaty ground in Hokkaido, Japan. Although the site was characterized by extremely soft peaty ground, a stable, high embankment 11.8 m in thickness was successfully constructed through the combination method. A consolidation-accelerating improvement from the PVD and a reinforcement eŠect from the steel grid were clearly observed, and settlement of the PVD-improved peat layer corresponded roughly with Barron's solution with consideration to well resistance. However, it was necessary to make the coe‹cient of consolidation nine times as large as that seen in the results of oedometer testing. The surcharge embankment allowed a reduction of the coe‹cient of secondary consolidation for the overconsolidated peat layer (overconsolidation ratio: approx. 1.13) to approximately 60z that of the normal consolidated layer.

show abstract

“…Preloading/surcharging in combination with vertical drains is the most widely applied technique used to improve the geomechanical properties of peat and other organic soil deposits (Mesri and Ajlouni, 2007;Mesri et al, 1997;Santagata et al, 2008). However, several investigators (Lake, 1961(Lake, , 1963McNulty, 1991;Mesri and Ajlouni, 2007) have suggested that vertical (sand) drains have little effect in accelerating the settlement rate for fibrous peat, considering the peat's high initial permeability and dominant creep effects.…”

Section: Introductionmentioning

confidence: 99%

Effect of salt grain additions on fibrous peat consolidation

Zhang

O’Kelly

2015

Proceedings of the Institution of Civil Engineers - Ground Impr

View full text Add to dashboard Cite

Peat has been considered a problematic geotechnical material, with extremely high water content, low shear strength and high compressibility. Although initially high, fibrous peat undergoes dramatic reductions in permeability under compression, with secondary compression (creep) accounting for a large proportion of the settlement under loading. The key to accelerating the whole consolidation process for fibrous/hemic peats is to create a means of accelerating water flow from micropores (within the cellular structure) or humus contained in the peat. This paper presents the results of preliminary laboratory trials performed using the hydraulic consolidation (Rowe) cell apparatus to investigate a novel approach involving the addition of salt grains to fibrous peat towards accelerating its rate of primary consolidation and reducing its creep rate. Under similar loading conditions, salt-treated specimens were found to have reduced rate and magnitude of creep settlement, explained by larger volumes of micropore water expelled during primary consolidation.

show abstract

One-Dimensional Compression Behavior of a Soil with High Organic Matter Content

Cited by 59 publications

References 19 publications

Effects of decomposition on the compressibility of fibrous peat — A review

Effects of decomposition on the compressibility of fibrous peat — A review

Field Performance of PVD Combined with Reinforced Embankment on Peaty Ground

Effect of salt grain additions on fibrous peat consolidation

Contact Info

Product

Resources

About