scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Appropriate use of lime in the study of the physicochemical behaviour of stabilised lateritic soil under continuous water ingress

29 Dec 2020-Sustainability (MDPI AG)-Vol. 13, Iss: 1, pp 257
TL;DR: In this paper, the influence of leaching on the physicochemical behaviour and durability of lime-stabilised lateritic soil under continuous water ingress, simulating the typical experience in a tropical environment was evaluated.
Abstract: Lime stabilisation is one of the traditional methods of improving the engineering properties of lateritic soils for use as subgrade and foundation materials for the construction of road pavements and highway embankments. Understanding the mechanical performance of lime-stabilised lateritic subgrades in terms of their durability under continuous water ingress will improve environmental sustainability by conserving scarce natural resources and reducing the environmental impacts of repair and replacement of pavements. However, there are several conflicting reports on the durability of lime-stabilised soils subjected to continuous water ingress and harsh environmental conditions. Therefore, this paper evaluates the influence of leaching on the physicochemical behaviour and durability of lime-stabilised lateritic soil under continuous water ingress, simulating the typical experience in a tropical environment. Variations in the strength and durability of the lateritic soil at various lime contents (0, 2.5, 5, 7.5, 10, 15, and 20 wt.%) and soaking periods (3, 7, 14 and 28 days) were evaluated by performing the California bearing ratio tests before and after subjecting the lime-lateritic soil (LLS) samples to continuous leaching using two modified leaching cells. Furthermore, physicochemical analysis was performed to assess the variation of cation concentrations and changes in the physical properties of the pore fluid as the leaching time progressed from 3 to 28 days. The results show that the minimum strength reduction index of the soil corresponds to its lime stabilisation optimum (LSO). Electrical conductivity decreased monotonically and almost uniformly with an increase in leaching time, irrespective of lime content. So, too, was calcium concentration and to a lesser degree for pH and potassium concentration. Adverse changes in the physicochemical behaviour of the LLS samples occurred at lime contents below and slightly above the optimum lime content of the soil. Whereas permanent pozzolanic reactions occurred at lime contents above the LSO and thus resulted in a 45-fold increase in strength and durability. The results are significant for reducing the detrimental effect of the leaching-induced deterioration of flexible pavements founded on tropical floodplains.
Citations
More filters
Journal ArticleDOI
TL;DR: A comprehensive review of the literature that is divided into four research areas: evaluation of leaching measurement methods, leaching from recycled asphalt materials, the leaching characteristics of porous asphalt pavements, and waste-modified asphalt mixtures is provided in this paper .

11 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provided an understanding of the evolution of void ratio of the mixed materials during swelling at three different suction levels upon saturation as well as the soil water retention (SWR) during desaturation.
Abstract: Treated bentonite-rich soils used as liner materials in landfills may provide an effective solution to the problems of increased void ratios upon swelling at reduced suction as well as desiccation cracking when suction is increased during desaturation. Accordingly, this study provides an understanding of the evolution of void ratio of the mixed materials during swelling at three different suction levels upon saturation as well as the soil water retention (SWR) during desaturation. For the treatment process, low quantity of cement binder whose production leverages raw material resources with efficient dry-process kilns and the benefit of lower energy consumption were used. Results indicated increased mixed soils’ strength irrespective of increased fines content due to thixotropy. The mixed soils exhibited almost equal values of void ratios at different hydration stages, suggesting that slightly reduced expansion mostly affects the subsequent phases of moisture ingress at full saturation compared to the natural soils. Lower values of void ratio obtained at full saturation also suggests possible reduced infiltration of water into landfills. The observed increased moisture retention within the osmotic suction zone and a decrease in the same as the fines content increased in the mixed soils can aid contaminant encapsulation while also reducing desiccation cracking. The findings of this research are intended to serve as a benchmark for further studies using other sustainable materials for treatment of mixed soils.

9 citations

Journal ArticleDOI
TL;DR: In this paper , 5 mm plus crushed glass was added to the expansive clay subgrade at different percentages (0, 5, 10, 15, and 20%) by dry weight of the clay.

8 citations

Journal ArticleDOI
TL;DR: In this paper , the effect of varying gypsum concentrations of 0, 3, 6, and 9 wt% on the performance of sulfate soil stabilised with two lime levels (4 and 6 wt%).
Abstract: The role of gypsum level on the long-term strength and expansion of soil stabilised with different lime contents is not well understood. This research, therefore, studied the effect of varying gypsum concentrations of 0, 3, 6, and 9 wt% (equivalent to the sulfate contents of 0, 1.4, 2.8, and 4.2%, respectively) on the performance of sulfate soil stabilised with two lime levels (4 and 6 wt%). This was carried out to establish the threshold level of gypsum/lime (G/L) at which the increase in G/L ratio does not affect the performance of lime-stabilised sulfate soil. Both unconfined compressive strength (UCS) and expansion, along with the derivative thermogravimetric (DTG) analysis, were adopted to accomplish the present objective. Accordingly, the result indicated that the strength and expansion were proportional to the lime and sulfate content, of which a G/L ratio of 1.5 was the optimum case scenario for UCS, and at the same time, the worst-case scenario for expansion. This discovery is vital, as it is anticipated to serve as a benchmark for future research related to the design of effective binders for suppressing the sulfate-induced expansion in lime-stabilised gypseous soil.

6 citations

Journal ArticleDOI
TL;DR: In this paper , the authors discuss the correlation between railway track elements, failures, and the degradation of embankments in railway networks, and then compare the soil stabilisation techniques from multiple aspects.
Abstract: Railway transportation is one of the most advantageous modes of transportation because of its high capacity, which obviates the increasing demand for conveying passengers and cargo. However, high initial costs and ongoing maintenance costs (partially resulting from the degradation of the subgrade and embankments) are drawbacks. Besides, railway subgrade soil experiences a high impact load and alternate drying-wetting and freeze-thawing cycles. In order to counter these problems, various kinds of soil improvement have been employed to improve the engineering properties of soils and minimise embankment and subgrade degradation. Chemical, mechanical, and geosynthetic techniques are currently being used to improve railway embankments. Some methods, such as columnar systems and deep mixing, fortify embankment foundations or subsoil, while others (e.g. chemical binders) can be used as mixed material to stabilise embankments and subgrade soil to a shallow depth. Hence, this review paper first discusses the correlation between railway track elements, failures, and the degradation of embankments in railway networks, and then compares the soil stabilisation techniques from multiple aspects.

6 citations

References
More filters
Journal ArticleDOI
Fred G. Bell1
TL;DR: In this paper, three of the most frequently occurring minerals in clay deposits, namely, kaolinite, montmorillonite and quartz, were subjected to a series of tests.

1,035 citations


"Appropriate use of lime in the stud..." refers background in this paper

  • ...The dissolved compounds then react with Ca2+ ions to produce hydrated cementitious products responsible for strength gain and long-term stability of the stabilised soils [40,68,77]....

    [...]

  • ...Bell [68] observed that treating expansive clays with lime resulted in a decrease in γdmax with a corresponding increase in wopt under similar compaction energy....

    [...]

  • ...Bell [68] noted that the lime fixation point of most soils, which is traditionally lower than the OLC, ranges between 1% and 3% lime by dry weight of soil....

    [...]

  • ...decrease in the DDL thickness, and hence causes a decrease in the liquid limit of the soil [68]....

    [...]

  • ...The marked reduction in dry unit weight could be ascribed to the agglomeration of the soil particles with the instantaneous formation of gelatinous compounds, in addition to the low specific gravity of the stabiliser [28,68,76]....

    [...]

Journal ArticleDOI
TL;DR: In this paper, the strength development in cement-stabilized silty clay is analyzed based on microstructural considerations, which includes water content, curing time, and cement content.

447 citations


"Appropriate use of lime in the stud..." refers background in this paper

  • ...Hence for silica-rich residual soils, further increase in liquid limit is usually triggered by the enhancement of the cation exchange capacity, due to the highly alkaline environment produced by the dissolution of Ca(OH)2, which increases the pH of the pore fluid [74]....

    [...]

  • ...Hence for silica-rich residual soils, further increase in liquid limit is usually triggered by the enhancement of the cation exchange capacity, due to the highly alkaline environment produced by the dissolution of Ca(OH) , which increases the pH of the pore fluid [74]....

    [...]

  • ...Furthermore, the increase in wopt was as a result of an increase in pore size and water-holding capacity within the flocculated soil fabric, coupled with the high demand of water needed for mid- to long-term pozzolanic reactions [74]....

    [...]

Journal ArticleDOI
TL;DR: In this article, the authors found abundant thaumasite, a complex calcium-silicate-hydroxide-sulfate-carbonate-hyd rate mineral, forming a solid solution series with ettringite.
Abstract: Expansive reactions between lime and sulfate-bearing clay soils have attracted little attention until relatively recently. Lime treatment of Stewart Avenue in Las Vegas, Nevada, had induced heave in excess of 12 in. Heaved areas are found to contain abundant thaumasite, a complex calcium-silicate-hydroxide-sulfate-carbonate-hyd rate mineral. Thaumasite forms a solid solution series with ettringite, a calcium-aluminum-hydroxide-sulfate-hy drate mineral. In the presence of aluminum, ettringite forms first and is replaced by thaumasite only at temperatures below 15°C. The mechanism of heave is a complex function of available water, the percentage of soil clay, and ion mobility. Only the long-term possolanic chemistry of normal lime-soil reactions is disrupted. Cation exchange, agglomeration, and carbonation are unaffected. With the present state of knowledge, lime-induced heave is difficult to predict for all but most obvious conditions.

365 citations

Journal Article
TL;DR: In this paper, the authors describe the reaction of LIME and soil to changes in the PLASTICITY, SWELL, SHRINKAGE or COMPRESSIVE STRENGTH of the soil.
Abstract: THE USE OF HYDRATED LIME, CA/OH/2, FOR MODIFYING, UPGRADING, AND STABILIZING SOILS IS INCREASING GREATLY. THIS MEANS HIGHWAY LABORATORIES HAVE HAD THEIR WORK LOADS INCREASED, AND IN MANY INSTANCES, MORE THAN DOUBLED FOR A PARTICULAR JOB. BEFORE THE ADVENT OF THE USE OF LIME, THE LABORATORY WAS FINISHED WITH TESTING WHEN A SOIL WAS CLASSIFIED AS UNSUITABLE. NOW THE SAME SOIL IS TESTED AND RETESTED TO FIND THE PERCENTAGE OF LIME REQUIRED TO BRING THE SOIL WITHIN SPECIFICATIONS. IN MOST CASES THE PERCENTAGE IS DETERMINED BY COMPRESSIVE TESTS, ATTERBERG LIMITS TESTS, OR BOTH. THE REACTION OF LIME AND SOIL CAN BE DESCRIBED AS A SERIES OF CHEMICAL REACTIONS. THE RESULTS OF THESE REACTIONS ARE EXPRESSED AS A CHANGE IN THE PLASTICITY, SWELL, SHRINKAGE OR COMPRESSIVE STRENGTH OF THE SOIL. THEREFORE, A QUICK OR SIMPLE TEST IS NEEDED TO SHOW THE AMOUNT OF LIME REQUIRED TO REACT CHEMICALLY WITH A SOIL TO BRING ABOUT THESE PHYSICAL CHANGES TO AN OPTIMUM DEGREE. LABORATORY TESTS, INVOLVING MINERALOGICAL, PHYSICAL AND CHEMICAL CHARACTERISTICS OF UNTREATED AND LIME-TREATED SOILS HAVE PROVEN THAT PH TESTS CAN BE USED TO DETERMINE THE OPTIMUM LIME REQUIREMENTS OF A SOIL. /AUTHOR/

337 citations


"Appropriate use of lime in the stud..." refers background in this paper

  • ...Eades and Grim [38] reported that a highly alkaline environment, which generally corresponds to a pH value of 12.4, is required to initiate pozzolanic reactions that enhance the crystallisation of cementitious products (C-S-H and C-A-H), due to the reactions between the dissolved Ca ions of lime and Si and Al ions of the clay minerals....

    [...]

  • ...Eades and Grim [38] reported that a highly alkaline environment, which generally corresponds to a pH value of 12....

    [...]

  • ...Eades and Grim [38] reported that a highly alkaline environment, which gen-...

    [...]

Journal ArticleDOI
TL;DR: In this paper, a series of laboratory tests were conducted on a highly expansive clay soil treated with lime in order to study the lime-soil reaction over a short term and the progression of the pozzolanic reaction over longer term.

301 citations


"Appropriate use of lime in the stud..." refers result in this paper

  • ...Similar trends in EC values have been observed by [33,34,84]....

    [...]

Trending Questions (1)
Does calcined soil improve the resistance of paving concrete against melting and freezing phenomena?

The provided paper does not mention anything about calcined soil or its effect on the resistance of paving concrete against melting and freezing phenomena.