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22-05-2021 | State-of-the-Art Review

A Review on Chemical Stabilization of Peat

Published in: Geotechnical and Geological Engineering | Issue 8/2021

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Abstract

Peat is a problematic or weak soil derived from fossilized organic material. The characteristics of peat like low shear strength (3–16 kPa), high water holding capacity (up to 850%), high compressibility with an initial void ratio in the range of 5–15 and chances of decaying further as time passes makes it unsuitable for the foundation. Therefore, for any infrastructure development in peat, its stabilization is inevitable. The chemical stabilization includes the use of conventional binders like lime and cement and non-conventional binders like fly ash, rice husk ash, ground granulated blast-furnace slag (GGBS) and silica fume. Further, in conventional stabilization, an extra amount of stabilizer (5–10%) is required to compensate the high-water cement ratio responsible for producing a lot of heat of hydration, leading to the failure of soil and the structure built over it. However, the use of non-conventional binder from agricultural and industrial by-products can partially replace conventional binders in which hydration takes place gradually. These by-products can be further activated by the alkaline solution to form ‘geopolymer’, which has shown better mechanical strength, workability, durability and complete replacement of conventional binders in soil stabilization. Therefore, the use of geopolymer in peat stabilization would be a blessing towards sustainable development.

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Title: A Review on Chemical Stabilization of Peat
Publication date: 22-05-2021
Published in: Geotechnical and Geological Engineering / Issue 8/2021
Print ISSN: 0960-3182
Electronic ISSN: 1573-1529
DOI: https://doi.org/10.1007/s10706-021-01857-1

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