Ground Improvement. On Quality Control for Shallow Soil Stabilization Method by Cement.

Traditional soil stabilization by chemical additives such as cement and lime is a well-established technique for ground improvement of problematic soils. However, with the advantage of lower carbon emission and energy consumption, fly-ash-based geopolymer has recently become an attractive alternative to traditional stabilizers. Nevertheless, the literature lacks systemic approaches that assist engineers to apply this promising binder for soil stabilization, including the proper dosages required for an effective treatment. This paper introduces a systematic approach to assess the applicability of fly-ash-based geopolymer for stabilization of clay soils, through a comprehensive experimental program where engineered and natural clays were examined and evaluated, including soil compaction, plasticity, compressive strength, durability, pH level, and impact of pulverization. The results revealed several factors that influence the level of enhancement of geopolymer-treated clays, including the soil mineralogy, plasticity–activity properties, geopolymer concentration, curing time, and pulverization.

Download Full-text

Geotechnical properties of reinforced clayey soil using nylons carry’s bags by products

MATEC Web of Conferences ◽

10.1051/matecconf/201816201020 ◽

2018 ◽

Vol 162 ◽

pp. 01020 ◽

Cited By ~ 1

Author(s):

Nahla Salim ◽

Kawther Al-Soudany ◽

Nora Jajjawi

Keyword(s):

Soil Stabilization ◽

Clayey Soil ◽

Ground Improvement ◽

Soft Soil ◽

Liquid Limit ◽

Waste Material ◽

Industrial Wastes ◽

Dry Density ◽

Maximum Dry Density ◽

Replacement Technique

All structures built on soft soil may experience uncontrollable settlement and critical bearing capacity. This may not meet the design requirements for the geotechnical engineer. Soil stabilization is the change of these undesirable properties in order to meet the requirements. Traditional methods of stabilizing or through in-situ ground improvement such as compaction or replacement technique is usually costly. Now a safe and economic disposal of industrial wastes and development of economically feasible ground improvement techniques are the important challenges being faced by the engineering community. This work focuses on improving the soft soil brought from Baghdad by utilizing the local waste material for stabilization of soil, such as by using “Nylon carry bag’s by product” with the different percentage and corresponding to 1 %, 3% and 5% (the portion of stabilizer matters to soil net weight) of dried soil. The results indicated that as Nylon’s fiber content increases, the liquid limit decreases while the plastic limit increases, so the plasticity index decreases. Furthermore, the maximum dry density decreases while, the optimum moisture content increases as the Nylon’s fiber percentage increases. The compression index (decreases as the Nylon’s fiber increases and provides a maximum of 43% reduction by adding 5% nylon waste material. In addition, the results indicated that, the undrained shear strength increases as the nylon fiber increases.

Download Full-text

Shear Strength of BC-Soil Admixed with Lime and Bio-Enzyme

Materials Science Forum ◽

10.4028/www.scientific.net/msf.969.327 ◽

2019 ◽

Vol 969 ◽

pp. 327-334

Author(s):

C. Jairaj ◽

M.T. Prathap Kumar ◽

H. Muralidhara

Keyword(s):

Shear Strength ◽

Soil Stabilization ◽

Morphological Changes ◽

Ground Improvement ◽

High Strength ◽

Sem Analysis ◽

Dry Density ◽

Test Results ◽

Maximum Dry Density ◽

Lime Content

This BC Soil are expansive in nature and are problematic because of low shear strength and high compressibility. Review of literatures have proven that addition of lime imparts high strength with a corresponding reduction in swell of BC soils. In addition, Bio-enzymes have also been found to play a key role as activators in improving the characteristics of clayey soils such as BC soil. Development and use of non-traditional ground improvement techniques such as bio-enzymes in combination with lime for soil stabilization helps to reduce the cost and the detrimental effects on the soil environment. In the present study lime and bio-enzymes were used as soil stabilizing agents. Compaction test results on BC soil admixed with different percent of lime indicated that 3% addition lime gives higher maximum dry density of 17kN/m3 with OMC of 21% compare to other addition of lime percentages. Keeping 3% of lime as optimum lime content(OLC), BC Soil was admixed with different dosages of Bio-enzymes 25ml/m3, 50ml/m3, 100 ml/m3,150ml/m3, and 200ml/m3 along with OLC was tested for compaction and unconfined compressive strength(UCC). Further UCC test was carried out for different curing period of 0, 7, 15, 30, and 60 Days to analyse the long term effect of BC soil admixed with bio-enzymes with and without lime content. Morphological and chemical analysis was done by using XRD and SEM analysis, from all the test results it was found that 3%OLC + 75ml/m3 of bio-enzymes for 7 day of curing gives higher UCC of 450 kPa. From the SEM it was found that better bond between particles found to develop in bio-enzyme+ lime admixed BC soil in comparison with lime alone admixed BC soil. XRD studies indicated morphological changes in crystallinity and structure of stabilized BC soil in comparison to BC soil alone.

Download Full-text

Compaction and Collapse Characteristics of Dune Sand Stabilized with Lime-Silica Fume Mix

Earth Sciences Research Journal ◽

10.15446/esrj.v20n2.50724 ◽

2016 ◽

Vol 20 (2) ◽

pp. 1 ◽

Cited By ~ 5

Author(s):

Mohammed Y. Fattah ◽

Hasan H. Joni ◽

Ahmed S. A. Al-Dulaimy

Keyword(s):

Silica Fume ◽

Soil Stabilization ◽

Ground Improvement ◽

Construction Materials ◽

California Bearing Ratio ◽

Dune Sand ◽

Dune Sands ◽

Maximum Percentage ◽

Collapse Characteristics ◽

Sand Stabilized

The purpose of this research is to assess the suitability of dune sands as construction materials. Moreover, such a goal is considered beneficial in determining appropriate methods for soil stabilization or ground improvement and to assessing the suitability of dune sands as subgrade layer for carrying roads and rail foundation. Dune sand samples were collected from a region in Baiji area in Salah-Aldeen governorate, North of Iraq. A grey-colored densified silica fume (SF) and lime (L) are used. Three percentages are used for lime (3%, 6%, and 9%), and four rates are used for silica fume (3%, 6%, 9% and 12%) and the maximum percentage of silica fume is mixed with the proportions of lime. Unsoaked California Bearing Ratio (CBR) on compacted dune sands treated dune sands with L-SF by mixing and cured for one day. The increasing in CBR ranged between 443 – 707% at 2.54 mm penetration and 345 – 410% at 5.08 mm penetration. ResumenEl propósito de esta investigación es evaluar el uso de arena de dunas como materiales de construcción. Además, este objetivo permite determinar los métodos apropiados para la estabilización del suelo, el mejoramiento del terreno y la evaluación de pertinencia de la arena de dunas en capas subbase para carreteras y cimientos férreos. Se recolectaron muestras de arena de dunas en el área de Baiji, del comisionado Salah-Aldeen, al norte de Irak. Se utilizó vapor de óxido de silicio (SF, en inglés), grisáceo y densificado, y óxido de calcio (L). Se utilizaron tres porcentajes para el óxido de calcio (3 %, 6 % y 9 %), y cuatro para el óxido de silicio (3 %, 6 %, 9% y 12%) y el máximo porcentaje del óxido de silicio se mezcló con las proporciones de óxido de calcio. Se realizó en seco el Ensayo de Relación de Soporte de California (del inglés California Bearing Ratio, CBR) en arena de dunas compactada y tratada con la mezcla L-SF curada durante un día. El incremento en el ensayo CBR osciló entre 443-707 % en la penetración de 2.5 mm y 345-410 % en la penetración de 5.08 mm.

Download Full-text

WETTING AND DRYING RESISTANCE OF LIME-STABILIZED EXPANSIVE SOILS MODIFIED WITH NANO-ALUMINA

Elektronički časopis građevinskog fakulteta Osijek ◽

10.13167/2021.22.6 ◽

2021 ◽

Vol 12 (22) ◽

pp. 70-80

Author(s):

Jijo James ◽

◽

S V Sivapriya ◽

Sajid Ali ◽

T R Madhu ◽

...

Keyword(s):

Soil Stabilization ◽

Expansive Soils ◽

Ground Improvement ◽

Primary Objective ◽

Optimal Combination ◽

Construction Sites ◽

Wetting And Drying ◽

Nano Alumina ◽

Stabilized Soil ◽

Strength And Durability

Weak soil at construction sites necessitates ground improvement. Chemical stabilization is typically carried out using either lime or cement. The primary objective of this study was to assess the strength and durability of lime-stabilized soils modified with nano-alumina (NA). This study adopted the scientifically established initial consumption of lime (ICL) content for soil stabilization. In addition, nano-alumina was added in varying percentages as an auxiliary additive. It was observed that 0.5 % of nano-alumina was optimal with respect to the ICL for maximizing the soil stabilization. The stabilized soils were cured for 0, 7, 14, and 28 days. Post-curing testing revealed that the strength increased sixfold for the optimal combination, compared with the virgin soil. To understand the durability behavior of the optimal combination, the stabilized soil specimens were subjected to wetting and drying cycles after 28 days of curing. The optimal combination was nearly as durable as that of the lime-stabilized soil subjected to five cycles of wetting and drying.

Download Full-text

Statistically Quantifying the Uncertainty in Strength of Marine Clay Stabilized by a Type of Portland-Fly Ash Cement

Advances in Civil Engineering ◽

10.1155/2021/6654802 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Zhi-Ren Zhu ◽

Qiang-Qiang Cheng ◽

Yang-Yang Chen ◽

Elton J. Chen ◽

Yuan Su

Keyword(s):

Monte Carlo Simulation ◽

Quality Control ◽

Fly Ash ◽

Soil Stabilization ◽

Simulation Method ◽

Monte Carlo Simulation Method ◽

Marine Clay ◽

Operational Parameter ◽

Binder Concentration

This study deals with the variation in strength of clays stabilized by a special binder—the CEM II/B-V type of Portland-fly ash cement. Two sources of uncertainties were examined, that is, the uncertainty in cement fraction in the binder, and the nonuniformity in binder concentration resulted from the process of mixing binder slurry with in situ clays. These two uncertainties were quantitatively described as two random variables, and the analyses were conducted through the Monte Carlo simulation method. Results indicate that the strength is insensitive to the cement fraction in the binder but is sensitive to the binder concentration; the variation of the latter even results in an amplified variation of strength. The variation of binder concentration is proposed to be linked up with the variation of strength through the operational parameter of blade rotation number. By doing so, the results could benefit designers in quality control prior to the construction of soil stabilization.

Download Full-text