Synthesis of a one-part geopolymer system for soil stabilizer using fly ash and volcanic ash

A novel approach one-part geopolymer was employed to investigate the feasibility of enhancing the strength of in-situ soil for possible structural fill application in the construction industry. Geopolymer precursors such as fly ash and volcanic ash were utilized in this study for soil stabilization. The traditional geopolymer synthesis uses soluble alkali activators unlike in the case of ordinary Portland cement where only water is added to start the hydration process. This kind of synthesis is an impediment to geopolymer soil stabilizer commercial viability. Hence, solid alkali activators such as sodium silicate (SS), sodium hydroxide (SH), and sodium aluminate (SA) were explored. The influence of amount of fly ash (15% and 25%), addition of volcanic ash (0% and 12.5%), and ratio of alkali activator SS:SH:SA (50:50:0, 33:33:33, 50:20:30) were investigated. Samples cured for 28 days were tested for unconfined compressive strength (UCS). To evaluate the durability, sample yielding highest UCS was subjected to sulfuric acid resistance test for 28 days. Analytical techniques such as X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscope/energy-dispersive X-ray spectroscopy (SEM/EDX) were performed to examine the elemental composition, mineralogical properties, and microstructure of the precursors and the geopolymer stabilized soil.

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Black Cotton Soil Stabilization by Using Fly Ash - Kota Stone Slurry Mix

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.39086 ◽

2021 ◽

Vol 9 (11) ◽

pp. 1699-1703

Author(s):

Phoolwanti Nanda

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Unconfined Compressive Strength ◽

Soil Stabilization ◽

Atterberg Limits ◽

Black Cotton Soil ◽

Strength Development ◽

Dry Density ◽

X Ray ◽

Soil Stabilizer

Abstract: The usage of waste material for stabilizing black cotton soil has been a sustainable interest. Kota stone slurry is a waste from kota stone and fly ash is a waste from industries containing high amount of sodium and magnesium, was used as a soil stabilizer for blac cotton soil improvement in this study. This research investigated the effects of sizes and percentages of kota stone slurry mix and fly ash on the physical and strength properties, which included particle size distribution, Atterberg limits, compaction, and unconfined compressive strength (UCS) of blac cotton soil. Micro structural characterization, including the scanning electron microscopic, energy dispersive X-ray spectroscopy, and X-ray diffraction was conducted on both untreated and treated black cotton soil samples to examine the mechanism of strength development. The addition of kota stone slurry and fly ash reduced the water holding capacity, which then caused the reduction in soil plasticity (from 18 to 11%) and optimum water content (from 20 to 16%) along with the increase in peak dry density (from 1.66 to 1.74 Mg/m3). The strength of black cotton soil may increased from 50 to almost 220 kPa. The optimum kota stone slurry and fly ash contents, providing the highest UCS, were at 20 and 30% for 0.063 mm kota stone slurry and fly ash and 0.15 mm kota stone slurry and fly ash, respectively. The UCS improvement of treated marine clay is attributed to the formation of cementation compounds, mainly aluminum magnesium silicate hydrate (A–M–S–H). The outcome of this research will allow the use of RBT as a low-carbon soil stabilizer across civil engineering applications. Keywords: Stablization, Fly ash, kota stone slurry, Atterberg limits, Compaction, and unconfined compressive strength

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Gene-Expression Programming-Based Model for Estimating the Compressive Strength of Cement-Fly Ash Stabilized Soil and Parametric Study

Infrastructures ◽

10.3390/infrastructures6120181 ◽

2021 ◽

Vol 6 (12) ◽

pp. 181

Author(s):

Van-Ngoc Pham ◽

Erwin Oh ◽

Dominic E. L. Ong

Keyword(s):

Gene Expression ◽

Compressive Strength ◽

Fly Ash ◽

Calcium Oxide ◽

Parametric Study ◽

Soil Stabilization ◽

Gene Expression Programming ◽

Superior Performance ◽

Stabilized Soil ◽

Research Findings

The study aims to develop a reliable model using gene-expression programming (GEP) technique for estimating the unconfined compressive strength (UCS) of soil stabilization by cement and fly ash. The model considered the effects of several parameters, including the fly ash characteristics such as calcium oxide (CaO) content, CaO/SiO2 ratio, and loss of ignition. The research results show that the proposed model demonstrates superior performance with a high correlation coefficient (R > 0.955) and low errors. Therefore, the model could be confidently applied in practice for a variety of fly ash qualities. Besides, the parametric study was conducted to examine the effect of fly ash characteristics on the strength of soil stabilization. The study indicates that if the fly ash contains a high amount of calcium oxide, the strength of fly ash stabilized soil is significant. In addition, fly ash could be used in combination with cement to increase the strength of the mixture. A fly ash replacement ratio is suggested from 0.19 to 0.35, corresponding to the total binder used from 10% to 30%. The research findings could help engineers in optimizing the fly ash proportion and estimating the UCS of soil stabilization by cement and fly ash.

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Chemical Stability and Leaching Behavior of One-Part Geopolymer from Soil and Coal Fly Ash Mixtures

Minerals ◽

10.3390/min8090411 ◽

2018 ◽

Vol 8 (9) ◽

pp. 411 ◽

Cited By ~ 9

Author(s):

April Tigue ◽

Roy Malenab ◽

Jonathan Dungca ◽

Derrick Yu ◽

Michael Promentilla

Keyword(s):

Fly Ash ◽

Chemical Stability ◽

Coal Fly Ash ◽

Embodied Energy ◽

Synthesis Process ◽

Attractive Alternative ◽

Alkali Activation ◽

Acid Attack ◽

X Ray ◽

Stabilized Soil

Aluminosilicate minerals have become an important resource for an emerging sustainable material for construction known as geopolymer. Geopolymer, an alkali-activated material, is becoming an attractive alternative to Portland cement because of its lower carbon footprint and embodied energy. However, the synthesis process requires typically a two-part system for alkali activation wherein the solid geopolymer precursor is mixed with aqueous alkali solutions. These alkali activators are corrosive and may be difficult to handle in the field-scale application. In this study, a one-part geopolymer in which coal fly ash was mixed with solid alkali activators such as sodium hydroxide and sodium silicate to form a powdery cementitious binder was developed. This binder mixed with soil only requires water to form the soil-fly ash (SO-CFA) geopolymer cement, which can be used as stabilized soil for backfill/foundation. This geopolymer product was then evaluated for chemical stability by immersing the material with 5% by weight of sulfuric acid solution for 28 days. Indication suggests that the geopolymer exhibited high resistance against acid attack with an observed increase of unconfined compressive strength even when the immersion time in acidic solution was increased to 56 days. The mineralogical phase, microstructure, and morphology of the material were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), respectively. Results not only confirmed the formation of gypsum due to acid attack but also indicated the dissolution of anorthite and albite that may have caused the microstructure to be composed of sodium aluminosilicate hydrate (N–A–S–H) and calcium (alumino) silicate hydrate (C(–A)–S–H) with poly(ferro-sialate-siloxo) and poly(ferro-sialate-disiloxo) networks. A column leaching test with deionized water was also performed on the soil-fly ash geopolymer to study the leachability of metals in the material. Results showed that arsenic exhibits higher mobility in the geopolymer as compared to that of cadmium, chromium, and lead.

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Review of Soil Stabilization Techniques: Geopolymerization Method one of the New Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.660.298 ◽

2015 ◽

Vol 660 ◽

pp. 298-304 ◽

Cited By ~ 7

Author(s):

Hazamaah Nur Hamzah ◽

Mohd Mustafa Al Bakri Abdullah ◽

Heah Cheng Yong ◽

Mohd Remy Rozainy Arif Zainol ◽

Kamarudin Hussin

Keyword(s):

Soil Stabilization ◽

Soft Soil ◽

Soil Samples ◽

Construction Process ◽

Soil Stabilizer ◽

Stabilized Soil ◽

Moderate Load ◽

Ucs Test ◽

Problematic Soil

This paper studies the effectiveness of soil stabilizer on the problematic soil or soft soil. It is subjected to instability and massive primary and long term consolidation settlements when subjected to even moderate load increases. The purpose of this study is to review the techniques and materials that have been used in the soil stabilization by previous researchers. The performance of the soil stabilizer for stabilization by means of strength has been highlighted in this study. Unconfined compressive strength (UCS) test was carried out on stabilized soil samples and the results that obtained were discussed. The use of these techniques and materials may provide an inexpensive and advantageous construction process. As a conclusion, the strength of soil can be increased by using these materials and techniques in soil stabilization. This paper gives a comprehensive report on stabilization techniques and materials that have been used for soft soil and also discuss the potential of geopolymerization technology to be one of the new soil stabilization techniques.

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Role of Curing Conditions and Precursor on the Microstructure and Phase Chemistry of Alkali-Activated Fly Ash and Slag Pastes

Materials ◽

10.3390/ma14081918 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1918

Author(s):

Marija Nedeljković ◽

Bahman Ghiassi ◽

Guang Ye

Keyword(s):

Fly Ash ◽

Analytical Techniques ◽

Limited Information ◽

Reaction Products ◽

Curing Conditions ◽

X Ray ◽

Phase Recognition ◽

Phase Chemistry ◽

Alkali Activated

Understanding the role of curing conditions on the microstructure and phase chemistry of alkali-activated materials (AAMs) is essential for the evaluation of the long-term performance as well as the optimization of the processing methods for achieving more durable AAMs-based concretes. However, this information cannot be obtained with the common material characterization techniques as they often deliver limited information on the chemical domains and proportions of reaction products. This paper presents the use of PhAse Recognition and Characterization (PARC) software to overcome this obstacle for the first time. A single precursor (ground granulated blast-furnace slag (GBFS)) and a binary precursor (50% GBFS–50% fly ash) alkali-activated paste are investigated. The pastes are prepared and then cured in sealed and unsealed conditions for up to one year. The development of the microstructure and phase chemistry are investigated with PARC, and the obtained results are compared with independent bulk analytical techniques X-ray Powder Fluorescence and X-ray Powder Diffraction. PARC allowed the determination of the type of reaction products and GBFS and FA’s spatial distribution and degree of reaction at different curing ages and conditions. The results showed that the pastes react at different rates with the dominant reaction products of Mg-rich gel around GBFS particles, i.e., Ca-Mg-Na-Al-Si, and with Ca-Na-Al-Si gel, in the bulk paste. The microstructure evolution was significantly affected in the unsealed curing conditions due to the Na+ loss. The effect of the curing conditions was more pronounced in the binary system.

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Use of class C fly ash for stabilization of fine-grained soils

E3S Web of Conferences ◽

10.1051/e3sconf/202019506001 ◽

2020 ◽

Vol 195 ◽

pp. 06001

Author(s):

Canan Turan ◽

Akbar Javadi ◽

Raffaele Vinai ◽

Nader Shariatmadari ◽

Raziyeh Farmani

Keyword(s):

Fly Ash ◽

Power Plants ◽

Soil Stabilization ◽

Clayey Soil ◽

Thermal Power ◽

Fine Grained ◽

Alternative Material ◽

Stabilized Soil ◽

Class C ◽

Burning Coal

Fine-grained soils may have undesired characteristics such as high swelling potential and low strength, thus requiring improvements. One of the stabilization methods involves the use of fly ash. Fly ash is a waste material obtained from burning coal in thermal power plants. The use of fly ash is encouraged as an alternative material for soil stabilization, due to its features such as pozzolanic properties and economic availability. This paper describes the results of an experimental study on stabilization of a clayey soil with fly ash. Unconfined compressive strength (UCS), triaxial and consolidation tests were carried out on samples of kaolinite mixed with class C fly ash at different percentages and cured for 1, 7, and 28 days, in order to study the effects of class C fly ash on the mechanical behaviour of the stabilized soil. The results showed that the inclusion of fly ash significantly improves the strength characteristics of the soil. Curing time was also found to have a significant effect on improving the properties of the soil.

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Application of Granulated Cable Plastic Waste for Soil Stabilization

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.760.171 ◽

2018 ◽

Vol 760 ◽

pp. 171-175

Author(s):

Martin Lidmila ◽

Marcel Jogl ◽

Wojciech Kubissa ◽

Roman Jaskulski ◽

Pavel Reiterman

Keyword(s):

Mechanical Properties ◽

Fly Ash ◽

Soil Stabilization ◽

Soil Mechanics ◽

Plastic Waste ◽

Partial Replacement ◽

Practical Utilization ◽

Standard Procedures ◽

Stabilized Soil ◽

Properties Of Soil

Paper deals with the assessment of practical utilization of granulated cable plastic waste (GCPW) for the production of stabilized soil layers in transport engineering. The main goal of the experimental work was the evaluation of the influence of GCPW on mechanical properties of soil stabilization based on the fluidized fly ash. Mechanical properties were investigated using standard procedures in soil mechanics. GCPW was dosed as a partial replacement of fluidized fly ash up to 30 %. It was concluded, that the studied level of replacement performs critical level, additional increasing of GCPW would lead to a decline of required mechanical properties. Besides, replacement by studied waste material caused lower values of the bulk density.

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Durability of Lime-Fly Ash Stabilized Soil Activated by Calcined Phosphogypsum

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.168-170.133 ◽

2010 ◽

Vol 168-170 ◽

pp. 133-138

Author(s):

Min Yang ◽

Yan Xie ◽

Ying Pang

Keyword(s):

Fly Ash ◽

Soil Stabilization ◽

Strength Loss ◽

Pozzolanic Reaction ◽

Initial Strength ◽

Road Base ◽

Base Materials ◽

Stabilized Soil ◽

Xrd Patterns ◽

Thermally Treated

Stabilized soil is widely used as road base and sub-base materials, and is sometimes used as covering for waste matter in China. In soil stabilization, the property of a locally available soil are usually modified though chemical stabilization[1]. Cement stabilization and lime stabilization are the two most commonly used methods. Lime-fly ash stabilized soil has been widely applied in road engineering due to its good integrity, great bearing capacity, high stiffness, and water-proofing quality[2-4]. One disadvantage of lime-fly ash stabilized soil is that without any additives, its inherent low initial strength makes it inappropriate for use under low-temperature conditions. Researchers have found that the pozzolanic reactivity among lime, fly ash, and soil contributes to the strength of lime-fly ash stabilized soil. To increase the initial strength of lime-fly ash stabilized soil, many approaches have been used to accelerate the pozzolanic reaction. Sulfate activation is one of the methods that has been widely investigated, specifically, Na2SO4 and CaSO4[5]. PG, another sulfate, has also been investigated. However, existing studies have limited to the investigation of the development of strength of the stabilized soil as road base and sub-base materials. The effect of PG on the durability of stabilized soil has rarely been implicated. This work aims to study the effect of thermally treated PG (400°C) on the properties of durability, in addition to other aspects, of lime-fly ash stabilized soil. Lime-fly ash stabilized soil with different proportions of calcined PG were prepared and cured at normal conditions for 7 d and 28 d. Mass loss and strength loss under different treatments were determined. X-ray diffraction(XRD) patterns and scanning electron microscopy(SEM) photos were examined to gauge whether improvements in the performances of the stabilized soil can be obtained by use of thermally treated PG.

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Potential of Soil Stabilization Using Ground Granulated Blast Furnace Slag (GGBFS) and Fly Ash via Geopolymerization Method: A Review

Materials ◽

10.3390/ma15010375 ◽

2022 ◽

Vol 15 (1) ◽

pp. 375

Author(s):

Syafiadi Rizki Abdila ◽

Mohd Mustafa Al Bakri Abdullah ◽

Romisuhani Ahmad ◽

Dumitru Doru Burduhos Nergis ◽

Shayfull Zamree Abd Rahim ◽

...

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

Soil Stabilization ◽

Road Construction ◽

Granulated Blast Furnace Slag ◽

Stabilized Soil ◽

Ucs Test ◽

Alkali Activated Binders ◽

Furnace Slag

Geopolymers, or also known as alkali-activated binders, have recently emerged as a viable alternative to conventional binders (cement) for soil stabilization. Geopolymers employ alkaline activation of industrial waste to create cementitious products inside treated soils, increasing the clayey soils’ mechanical and physical qualities. This paper aims to review the utilization of fly ash and ground granulated blast furnace slag (GGBFS)-based geopolymers for soil stabilization by enhancing strength. Previous research only used one type of precursor: fly ash or GGBFS, but the strength value obtained did not meet the ASTM D 4609 (<0.8 Mpa) standard required for soil-stabilizing criteria of road construction applications. This current research focused on the combination of two types of precursors, which are fly ash and GGBFS. The findings of an unconfined compressive strength (UCS) test on stabilized soil samples were discussed. Finally, the paper concludes that GGBFS and fly-ash-based geo-polymers for soil stabilization techniques can be successfully used as a binder for soil stabilization. However, additional research is required to meet the requirement of ASTM D 4609 standard in road construction applications, particularly in subgrade layers.

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Experimental Study on Mechanics and Water Stability of High Liquid Limit Soil Stabilized by Compound Stabilizer: A Sustainable Construction Perspective

Sustainability ◽

10.3390/su13105681 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5681

Author(s):

You Wang ◽

Hongdong Zhang ◽

Zhuangzhuang Zhang

Keyword(s):

Fly Ash ◽

Liquid Limit ◽

Inorganic Materials ◽

Sustainable Construction ◽

Water Stability ◽

Soil Stabilizer ◽

Orthogonal Experiments ◽

Stabilized Soil ◽

Diffraction Patterns ◽

Strength And Stiffness

Sustainable highway construction and operation are threatened by high-liquid-limit soil with low strength and poor water stability in Dongting Lake areas. In order to obtain a soil stabilizer that can effectively improve its strength and water stability, first the author selected inorganic materials (cement, quicklime and fly ash) and sulfonated oil (SO) as the main components of the composite soil stabilizer. Then, a series of single admixture tests were carried out to explore the strength and water stability mechanism of single admixture stabilized soil. Finally, a series of orthogonal experiments and cost analyses were carried out to obtain the formula of the composite stabilizer. According to the results of single doping, inorganic materials can significantly enhance the strength and stiffness of high-liquid-limit soil. The content of SO has a strong correlation with the water stability of high-liquid-limit soil. On a microscopic scale, X-ray diffraction patterns and scanning electron microscopy images explained this law. According to the orthogonal results, the formula of the composite soil stabilizer is: cement 4.5%, quicklime 1.5%, fly ash 2.5%, and SO 0.2%. This paper provides a method to improve high-liquid-limit soil, which is beneficial to sustainable construction and operation of the highway.

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