Ionic Soil Stabilizer Research Articles

Exploring the microstructure characteristics and mechanical behavior of the ionic soil stabilizer-treated clay

As a high-efficiency and environment-friendly stabilizer material, ionic soil stabilizer (ISS) has been widely used in construction industries. However, the microstructure characteristics and mechanical behavior of the treated soil still need a case study based on vary characteristics of soils and different treatments. In this paper, microscopic and macroscopic testing methods were adopted to explore the microstructure characteristics and mechanical behavior of the acidic ISS-treated clay versus the traditional alkaline lime and cement-treated clay. The results indicate that the soil particles become much more flocculated because of the ion exchange reaction between the soil and the ISS relying on the unique molecular structure of the ISS. The unconfined compressive strength (UCS) significantly increases, but still could not satisfy the requirement of road bearing capacity. However, the UCS improves rapidly with the increase of alkaline lime and cement. In addition, there is a benefit-period when the UCS of acidic and alkaline stabilizer-treated soil is greater than that of lime and cement-treated soil, whereas the strength of lime and cement-treated soil is lower than that of the combined treated one after this period. This study investigates the microstructure characteristics and mechanical behavior of the ISS-treated clay, which provides a theoretical and scientific support for appropriate road construction.

Chemical Treatment of a Highly Expansive Clay Using a Liquid Ionic Soil Stabilizer

Expansive soils for residential projects are often treated with liquid ionic soil stabilizer (LISS) using deep pressurized injection method. Liquid ionic soil stabilizers have a long history of application in practice. However, there is limited knowledge and experimental evidence of their stabilization mechanism and effectiveness. This paper summarizes the research that investigated the effects of liquid ionic stabilizers on key engineering properties of a highly expansive clay from Carrollton, Texas, through comprehensive physical and mechanical testing and microscopic observation of untreated and treated soils. Test results before and after treatment were analyzed for two different treatment ratios: 1:300 and 1:150, showing a 53% swell reduction for treated soil compacted at the optimum moisture content (OMC) for treated soil, and 25% swell reduction for treated soil compacted at the OMC for the untreated soil. There was no significant improvement in unconfined compressive strength; noticeable improvement in stiffness was observed. The microscopic analysis showed a marked change in morphology and quantitative element composition, thus suggesting the occurrence of a reasonable degree of stabilization.

MICROSCOPIC MECHANISM OF SOLIDIFIED SILT WITH IONIC SOIL STABILIZER

The typical silt in Wuhan is solidified with Ionic Soil Stabilizer(ISS). The plasticity index of soil with different mix proportions is obtained through the test of Atterberg limits. The compressive properties, microstructure, specific surface area, chemical composition, energy spectrum analysis and cation exchange test are carried out before and after the solidification of silt with ISS. The macroscopic and microscopic mechanism of the solidification of silt with ISS are studied. The test results show that the compressive strength of silt treated with ISS decreases and porosity decreases. Ionic Soil Stabilizer promotes aggregation and condensation of soil particles, aggregates obviously increase, specific surface area decreases, specific surface energy decreases, and soil structure is denser. There is no change in the chemical composition of the silt before and after solidification. Cation exchange reaction occurs between the ISS and the counter ion layer on the surface of the silt colloid particles. The K+ and Na+ ions in the diluents of the curing agent are captured and adsorbed by the silt. The Ca2+ and Mg2+ ions on the surface of clay particles are resolved, which makes the thickness of the diffusion layer thinner, the ξ potential decreased, and the clay colloid particles coalesced. ISS improves the strength and stability of the soil particles, so as to achieve the purpose of soil modification and solidification.

Expansive Soil Treatment with Liquid Ionic Soil Stabilizer

Calcium-based stabilizers such as lime and cement control swell and shrinkage behavior and enhance strength properties for expansive soils through the formation of pozzolanic components. However, sulfate-bearing subgrade soils stabilized with calcium-based stabilizers might cause excessive swelling and shrinkage due to the formation of highly expansive minerals like ettringite and thaumasite. In this paper, one liquid ionic soil stabilizer (LISS) was evaluated as an alternative stabilizer used to control swelling and shrinkage behavior of expansive soils. A comprehensive laboratory experiment program including a linear shrinkage test, a one-dimensional swell test, and an unconfined compressive strength test, was designed and carried out on soils from Dallas, Texas before and after treatment. Three dosage levels of stabilizer and four different curing periods were investigated. Test results indicate that LISS is an effective stabilizing agent, which not only reduces swelling and soil plasticity but also increases soil strength. Furthermore, a similar type of LISS is utilized to treat the soil in Dallas via deep injection using a hydraulic pump. Field emission scanning electron microscopy results on the test soil showed that the stabilizing program is likely to work through clay flocculation and morphological variations in the clay particles.

The Influences of Freeze-Thaw Cycles on the Shear Strength of Expansive Soil Treated with Ionic Soil Stabilizer

A study of the shear strength of expansive soil treated with ionic soil stabilizer during freeze-thaw cycles is presented. The shear strength of treated expansive soil is greater than that of untreated expansive soil at room temperature, and it is evident that the moisture content plays a leading role in this result. After a freeze-thaw cycle the shear strength changes little for untreated soil, but decreases gradually after ionic soil stabilizer treatment. Shear strength reaches the lowest values after seven freeze-thaw cycles. Finally, the influence of freeze-thaw cycles on the porosity of expansive soil is analyzed using scanning electron microscopy, which shows that the porosity of both treated and untreated soil increases with the number of freeze-thaw cycles, although porosity of the treated sample changes little.

Experimental Study of Expansive Soil Improved by Ionic Soil Stabilizer

Based on expansive soil of Anyang district of Henan improved by Ionic Soil Stabilizer, expansive soil is tested in the free swelling ratio test and Shrinkage test. The results show that after mixing the ISS into expansive soil, free swelling ratio of expansive soil decreases, and performance of expansive soil is significantly weakened. When the ISS with the water volume ratio of 1: 250, a free expansion to minimize the expansive soil. And the ISS than without after adding ISS, expansive soils line shrinkage and shrinkage limit significantly reduced, indicating that the weak soil particles adsorbed on the surface of the part of bound water has been replaced with off the coupling strength between soil particles to strengthen, soil shrinkage deformation smaller.

Validation of the solidifying soil process using laser-induced breakdown spectroscopy

Although an Ionic Soil Stabilizer (ISS) has been widely used in landslide control, it is desirable to effectively monitor the stabilization process. With the application of laser-induced breakdown spectroscopy (LIBS), the ion contents of K, Ca, Na, Mg, Al, and Si in the permeable fluid are detected after the solidified soil samples have been permeated. The processes of the Ca ion exchange are analyzed at pressures of 2 and 3atm, and it was determined that the cation exchanged faster as the pressure increased. The Ca ion exchanges were monitored for different stabilizer mixtures, and it was found that a ratio of 1:200 of ISS to soil is most effective. The investigated plasticity and liquidity indexes also showed that the 1:200 ratio delivers the best performance. The research work indicates that it is possible to evaluate the engineering performances of soil solidified by ISS in real time and online by LIBS.

Micro-Treatment Mechanism Study on Ionic Soil Stabilizer Improving Clay

In order to study the treatment mechanism of the ionic liquid soil stabilizer, a series tests were performed for a typical soil, the red-brown clay. The basic physical parameters of typical soil were conducted by variety of tests, including particle size analysis, crucial water content coefficient, loss on ignition, organic matter content, etc. Furthermore, the treatment mechanism of the ionic soil stabilizer was analyzed, involving PH, conductivity, plasma emission spectra, scanning electron microscopy, X-ray diffraction and BET test. The results indicate: Firstly, the ionic soil stabilizer is a sulfonated oleoresin with the features of water soluble, high conductivity and strongly acidic, which exchanged with cations adsorbed on the surface of clay particles to reduce the thickness of hydrated film and the electric double layer thickness. Secondly, it reduced the mutual repulsion energy between soil particles and made the flaky particles of clay minerals contact closely. Finally, it made the particles of clay be close to each other and gradually formed larger particles. Hence, the clay became denser. Therefore, the research provided a theoretical foundation and practical basis for the wide application of the ionic soil stabilizer in China's highway construction.

Analysis of Durability Performance of Ionic Soil Stabilizer Improving Soil

In order to study the pavement performance of the soil that improved by ionic liquid soil stabilizer, the red-brown clay was concerned as the typical soil, mixed with the ionic soil stabilizer, the ordinary Portland cement and the hydrated lime, was tested to characterize its durability. The engineering classification of the typical soil was determined and the physical parameters of the ionic soil stabilizer was obtained, according to tests of the particle size analysis, crucial water content coefficient, organic matter content, PH, conductivity, plasma emission spectra, etc. In addition, the tensile strength, durability and shrinkage property were analyzed by split tests, freezing and thawing tests, fatigue tests and shrinkage tests. As a result, the typical soil was a kind of low liquid-limit clay, denoted by CL. The ionic soil stabilizer was a water soluble, high conductivity, strongly acidic sulfonated oleoresin. The ion exchange reaction between the soil and the ionic soil stabilizer begun after treating by the ionic soil stabilizer, and then the role of soil particles became stronger. Furthermore, the void between soil particles was decreased, the structure became closer, and then the tensile strength, durability and shrinkage property were improved. As mentioned above, the research provided theoretical foundation and practical support for using the ionic soil stabilizer in China's highway construction.

Compressive Strength Analysis of Ionic Soil Stabilizer Improving Soil

To explore the ionic liquid soil stabilizer improved soil mechanical properties, this experiment conducted liquid-plastic limit test and compaction test. On the basis of determining the optimal dosage of ionic soil stabilizer and mastering different mixture optimum moisture content and maximum dry density, the standard sample which consists of the Zhejiang red-brown clay and curing material including ionic soil stabilizer, cement and lime carried out the unconfined compressive strength test in different curing age and compaction degree. This paper analyzed the change reason of compaction and curing age about the stabilized soil. The results show that the ionic soil stabilizer has a significant effect on the compressive strength improvement of stabilized soil. Compared stabilized soil with traditional treatment soil, the compressive strength of stabilized soil has improved obviously with the increase of curing age and compaction degree. Research findings provide useful technical support and practice basis for promoting and applying ionic soil stabilizer in infrastructure construction.

Effect of ‘Ionic Soil Stabilizer 2500’on the Properties of Black Cotton Soil

This study was carried out to establish t he effect ofIonic Soil Stabilizer 2500 � (ISS 2500) on black cotton soil. Samples were collected along Dikwa �Gamboru Ngala road in North- East Nigeria. Initial results indicated that the black cotton soil could be expansive with over 60% passing the number200 sieve size. The ISS stabilizer is 100% organic and is derived from combined organic Sulphur and buffered acids that are combined as bi -sulphates. The ISS stabilizer dosages of 0%, 1ml, 2ml, and 3ml were mixed with 6000g weight of black cotton soil andtests were carried out to determine if improvement in properties would occur. For the pH tests carried out, there were increases in the acidity of the samples with increase in ISS content. Similarly, the redox potential showed consistent increase in value with increase in ISS content. However, the plasticity index which was expected to decrease in view of the increases in the redox potential, and the electrical conductivity decreased instead. The CBR test was conducted in accordance with energy levels usin g British light compaction method. Consequently, the CBR values increased marginally but below the specifications for soil -cement stabilization for road base materials. The ISS stabilizer has not produced a consistent set of results for inferences to be ma de on its effectiveness in improving the properties of black cotton soils to road base standards. Further tests are required on the long term effects of the stabiliser on black cotton soils.

Cation Exchange Detection in the Process of Ionic Soil Stabilizer Reinforcing Soil by Laser-Induced Breakdown Spectroscopy <sup></sup>

In order to study the process of ionic soil stabilizer (ISS) reinforcing different kinds of soil, kaolin, red clay, landslide soil, expansive soil and quartz sand ,the five kinds of standard soil samples were treated by ISS of ratio 1:100. After 24-hour soaking and oscillation treatment, the supernatant was detected by laser-induced breakdown spectroscopy (LIBS). Comparing with the samples had not been treated by ISS, got the information of cation exchange. Experimental results showed that, the cation exchange in different soil was various, landslide soil exchanged more cation, and the cation exchange of kaolin and quartz sand was less. These studies will provide the experimental basis for ISS reinforcing mechanism research.

Experimental Study on Dynamic Characteristics of Ionic Soil Stabilizer Reinforcing Red Clay

Based on the red clay of Wuhan reinforced by Ionic Soil Stabilizer, the red clay soil is treated by different matches of ISS at first, then is tested in the Atterberg limits test and dynamic triaxia test. The results show that the plastic index decreases, and the red clay were greatly improved under the dynamic condition, the maximum dynamic shear modulus ratio acquired an incensement of 27.72% on average after mixing the ISS into the red clay. In addition, It was concluded that the confining pressure influenced the dynamic shear modulus and damping ratio to a certain extent. Given the same strain conditions, with the incensement of confining pressure increases, the dynamic shear modulus increased and the damping ratio decreased. Moreover, when plotting the dynamic shear modulus versus the dynamic shear strain, the similar curve can be formed for both the natural soil and the modified one, the dynamic shear modulus monotonously decreased with the incensement of the dynamic shear strain. However, the value of dynamic shear modulus differed in the same shear strain between the natural soil and the soil modified by ISS.

Study on Ionic Soil Stabilizer Reinforcing Red Clay of Wuhan

With fast research and development, economic and effectual materials have been the focal point of all over the world all the time. This experiment studies and uses a new kind of economic and suitable Ionic Soil Stabilizer (ISS for short). Based on the red clay of Wuhan reinforced by Ionic Soil Stabilizer, the red clay is treated by different matches of ISS and water at first, then is tested in the unconfined compressive strength test, shrinkage test, free swell test, and spectrum test. The results show that unconfined compressive strength increases, and the linear shrinkage, shrinkage limit and free swell decrease after mixing the ISS into the red clay. In addition, spectrum tests show that after the red clay is treated by ISS, soil particles on the surface of the C elements had changed markedly, from scratch, confirmed the ISS elements combined with the role of soil particles.

Experimental Study on Ionic Soil Stabilizer Reinforcing Red Clay

In this research, a kind of Ionic Soil Stabilizer (ISS for short) is used as great extension of Ministry of Water Resources of the People’s Republic of China. Based on the red clay of Hanyan district of Wuhan reinforced by Ionic Soil Stabilizer, the red clay soil is treated by different matches of ISS and water at first, then is tested in the Atterberg limits test, dirct shear test and surface tension test. The results show that the plastic index decreases, and the cohesion increases after mixing the ISS into the red clay. In addition, Once ISS is dissolved in water, it can reduce the surface tension of water, and with the concentration increasing, the surface tension decreased. Finally the mechanism how ISS reinforces the red clay is analyzed by the aspect of the structure of pair-electricity layer and the Zeta potential.

Theory and practice of ionic soil stabilizer reinforcing special clay

The change in the thickness of water films of special clay particles such as sliding clay, red clay, and expansive clay is an important factor in producing geological disasters and geological environmental damage. In order to reduce the thickness of water films, ionic soil stabilizer (ISS) is used to treat sliding clay, red clay, and expansive clay. Direct shear test of sliding clay and shrinkage, free swell rate, zeta potential, and cation-exchange capacity of red clay and expansive clay are carried out. The results show that as the plastic indexes of special clay soil decrease, the shear strength of sliding clay increases, the shrinkage and free swell rate of red clay and expansive clay decrease, and the thickness of the water film thins after treatment with the ionic soil stabilizer. Therefore, the geological engineering disasters caused by changes in the thickness of water films of special clay can be effectively inhibited.

Mechanisms of Soil Stabilization with Liquid Ionic Stabilizer

Numerous commercial suppliers are marketing liquid chemical products for stabilizing pavement subgrade and base soils. These nontraditional chemical stabilizers may offer viable alternatives for stabilizing sulfate-rich soils where conventional lime or cement treatment can lead to excessive soil expansion. Typically sold as concentrated liquids that are diluted in water before application, these products may be less expensive to use than lime or cement. However, many transportation agencies are hesitant to specify nontraditional liquid stabilizers without better information on the stabilizing mechanisms and documented field experiences. To identify the mechanisms associated with one class of these products, a representative ionic soil stabilizer and a sodium montmorillonite clay were selected for a detailed physical-chemical study. Laboratory testing included chromatography, spectroscopy, X-ray diffraction, electron microscopy, and standard titration analyses. These tests have shown that the principal active constituents of the selected ionic stabilizer are d-limonene (a by-product of citrus processing) and sulfuric acid, which react to form a concentrated, low-pH solution of sulfonated limonene. The observed changes in clay chemistry following treatment indicated that this product would stabilize a soil by altering the clay lattice. The result is the formation of a more highly weathered, less-expansive clay structure. On the basis of this understanding of the underlying mechanisms, ionic stabilizers applied at sufficiently high application mass ratios may improve the properties of certain soils on some highway construction projects.