Stone Columns Research Articles

Behaviour of circular footings resting on a reinforced granular bed underlain by a single floating stone column

Behaviour of circular footings resting on a reinforced granular bed underlain by a single floating stone column

3-Dimensional numerical analysis of geosynthetic double-encased annulus stone columns

A geosynthetic double-encapsulated annulus stone column technique is proposed in this study to overcome limitations associated with conventional stone columns, such as limited lateral load-bearing capacity and potential issues related to aggregate dispersion in soft soils. Geosynthetic double-encapsulated annulus stone columns are consistent with conventional stone columns besides being confined in and around the surrounding soil. The performance of geosynthetic double-encapsulated annulus stone columns is primarily dependent upon their outer-to-inner diameter ratio. For this reason, comprehensive 3-dimensional numerical studies were carried out to evaluate the optimum outer-to-inner diameter ratio of the annulus stone column. The results suggest that the ultimate load-carrying capacity of an annulus stone column increases with an increasing ratio of outer to inner diameter until an optimum value. In addition, the double encapsulation enhances confinement, improving shear stiffness and reducing lateral bulging. However, the load-carrying capacity was substantially reduced beyond the critical outer-to-inner diameter ratio. A simple analytical model extending the theory of thin cylinders is also introduced to estimate the accumulated stresses and strains in the geosynthetic encasement. The proposed model operates within a simplified framework of elastic solutions that facilitate practising engineers to design and optimize geosynthetic encasements for enhanced structural performance.

Pull-out Bearing Capacity of Anchor Cables in Stone Columns: Field Experimental and Numerical Investigations

Pull-out Bearing Capacity of Anchor Cables in Stone Columns: Field Experimental and Numerical Investigations

Analytical Solutions for Composite Foundations Reinforced by Partially Penetrated Stone Columns and Vertical Drains

ABSTRACTWhen stone columns or vertical drains are applied to improve soils, it is common to face situations where the soft soil layer is too thick to be penetrated completely. Although consolidation theories for soils with partially penetrated vertical drains or stone columns are comprehensive, consolidation theories for impenetrable composite foundations containing both two types of drainage bodies have been few reported in the existing literature. Equations governing the consolidation of the reinforced zone and unreinforced zone are established, respectively. Analytical solutions for consolidation of such composite foundations are obtained under permeable top with impermeable bottom (PTIB) and permeable top with permeable bottom (PTPB), respectively. The correctness of proposed solutions is verified by comparing them with existing solutions and finite element analyses. Then, extensive calculations are performed to analyze the consolidation behaviors at different penetration rates, including the total average consolidation degree defined by strain or stress and the distribution of the average excess pore water pressure (EPWP) along the depth. The results show that the total average consolidation rate increases as the penetration rate increases; for some composite foundations with a low penetration rate, the consolidation of the unreinforced zone cannot be ignored. Finally, according to the geological parameters provided by an actual project, the obtained solution is used to calculate the settlement, and the results obtained by the proposed solution are in reasonable agreement with the measured data.

Bibliometric analysis of stone column research trends: A Web of Science perspective

Abstract Stone columns have garnered significant interest in geotechnical engineering as an effective ground improvement technique for enhancing the load-bearing capacity and mitigating settlement issues in soft soils. This study presents a comprehensive bibliometric analysis of scholarly literature on stone columns, utilizing data from the Web of Science database spanning from 1975 to 2023. The analysis aims to provide insights into publication trends, influential journals, key research institutions and authors, geographical distributions, and emerging themes in this domain. Through a systematic data curation process, 505 relevant publications were analyzed using Excel and VOSviewer software. The findings reveal a notable emphasis on geosynthetic encasements, load-settlement behavior, and soft soil reinforcement, with China being a major contributor. Over the past 48 years, the research has evolved from static loading to dynamic loading, sustainable structures, and artificial intelligence applications, as evidenced by the highly cited publications. This study maps the development, current state, and potential future directions of stone column research, serving as a valuable resource for researchers and practitioners in geotechnical engineering.

Predictive modeling of sustainable recycled materials for stone column construction

Climate change due to carbon dioxide emissions is one of the most significant global challenges. Sustainable recycled materials are recognized as a critical factor in mitigating climate change, representing a fundamental strategy for reducing gas emissions and preserving the environment. Promising sustainable recycled materials in construction, such as crushed asphalt, crushed concrete, crushed ceramic, and treated concrete offer numerous advantages, including reduced carbon dioxide (CO2)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{(CO}}_{2} )$$\\end{document} emissions, cost-effectiveness, increased strength, and enhanced mechanical properties. In this study, various machine learning techniques, including the support vector machine (SVM), multiple linear regression (MLR), gaussian process regression (GPR), and artificial neural network (ANN), are used to assess the effectiveness of sustainable recycled materials within stone columns. The MLR model was specifically utilized to predict the ultimate stress equation for these materials within stone columns. Forty-five constructed samples were used in developing the models. The effectiveness of each model was evaluated using various statistical assessment measures, including mean absolute error (MAE), absolute fraction of variation (R2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{R}}^{2}$$\\end{document}), and root mean square error (RMSE). The predictive model’s performance was validated using the k-fold cross-validation method. The ANN model with an R2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ ext{R}}^{2}$$\\end{document} value of 0.962 and an RMSE value of 7.268 kPa, performed better compared to GPR, SVM and MLR models. In summary, the results of the study indicate that the MLR model, utilizing the identified input parameters, can accurately predict the ultimate stress for different sustainable recycled materials. Implementing such technologies within the construction sector can expedite and reduce the cost of assessing material characteristics and the influence of input parameters.

Evaluation of the methods used for estimating the bearing capacity of stone columns

Stone columns have been utilized for several decades due to their ability to improve the mechanical behavior of weak and marginal soil deposits. Reducing the cost of a project necessitates accurate estimation of the stone column capacity. This paper considers the existing analytical methods for estimating the bearing capacity of stone columns and evaluate their prediction accuracy. For this purpose, the results of 36 full-scale field tests on footings supported by stone columns are considered, and the measured bearing capacity (QM) are compared with estimated bearing capacity (QE) values computed from 15 analytical solutions predicting the stone column capacity. For this comparison, five statistical approaches are employed in order to evaluate these 15 methods and identify the level of their prediction accuracy. Finally, the methods are ranked by the degree of accuracy with which they can estimate the load capacity. The findings of this research help designers and decision makers to choose a more reliable design method when dealing with stone columns.

Seismic resilience assessment of sheet-pile wharves in liquefiable soils using different liquefaction countermeasures

Seismic resilience assessment is essential for maintaining the functionality of sheet-pile wharves in liquefiable soils, preventing significant damages and minimizing losses during earthquakes. This study delves into the seismic resilience of sheet-pile wharves, focusing specifically on the effectiveness of four different liquefaction countermeasure techniques: anchor lengths, cement deep mixing, stone columns, and soil compaction. As such, an advanced two-dimensional (2D) Finite Element (FE) computational framework is established, motivated by a typical large-scale sheet-pile wharf configuration. Within this framework, a recently developed multi-yield surfaces plasticity model is employed, with the modeling parameters calibrated through undrained stress-controlled cyclic triaxial tests and a centrifuge test. Subsequently, the impacts of these liquefaction countermeasures on the seismic resilience of the sheet-pile wharves are systematically investigated. Additionally, the effectiveness of combining longer anchor lengths with the other three mitigation techniques to enhance the seismic resilience of the sheet-pile wharves are examined. It is demonstrated that the synergistic effects of different liquefaction countermeasures can further reduce the liquefaction potential, thereby improving the seismic resilience. Overall, the FE analysis technique and the resulting insights are highly significant for the seismic resilience assessment of equivalent sheet-pile wharves in liquefiable soils, particularly when implementing such liquefaction mitigation countermeasures.

Liquefaction Mitigation of Saturated Sand Using Ordinary, Filtered, and Geosynthetic-encased Stone Columns in Shaking Table Tests

Liquefaction Mitigation of Saturated Sand Using Ordinary, Filtered, and Geosynthetic-encased Stone Columns in Shaking Table Tests

Synthesis and performance study of amphoteric polymer suspension stabilizer for cementing slurry at ultra-high temperature

As the number of ultra-deep wells increases, maintaining the suspension stability of cement slurry at ultra-high temperatures becomes increasingly challenging; the development of a suspension stabilizer suitable for ultra-high temperature environments is imperative. Therefore, this study synthesized a temperature-resistant polymer suspension stabilizer (LHAP) using 2-acrylamide-2-methylpropanesulfonic acid (AMPS), N, N-dimethyl acrylamide (DMAA), 4-acryloylmorpholine (ACMO), and quaternary ammonium cationic hydrophobic long-chain monomer hexadecyl dimethylallyl ammonium chloride (DMAAC-16) as raw materials. It was applied to maintain the suspension stability of cement slurry at ultra-high temperatures. The molecular structure and molecular weight of LHAP were characterized and tested using infrared spectroscopy, nuclear magnetic hydrogen spectroscopy, and Ubbelohde viscometer. The thermal stability and viscosity-temperature performance of LHAP were measured using thermogravimetric analysis and rheometer, respectively. Through the segmented density difference testing of cement stone columns, the suspension stability effect of LHAP on cement slurry under high temperature was evaluated. The suspension stabilization mechanism of LHAP was studied through fluorescence probe testing, variable temperature UV visible light testing, variable temperature particle size distribution testing, Zeta potential analysis, Environmental Scanning Electron Microscopy (ESEM) analysis, and scanning electron microscopy (SEM) analysis. The results indicated that the polymer suspension agent LHAP had excellent temperature resistance, and the molecules didn’t undergo significant thermal degradation below 302 ℃. At high temperatures of 220 ℃, LHAP could maintain the suspension stability of cement slurry, and the segmented density difference of cement columns was less than 0.01 g/cm3. Mechanism analysis revealed that in addition to enhancing temperature resistance by introducing sulfonic acid groups and rigid rings, LHAP also effectively maintains the stability of the slurry suspension at ultra-high temperatures by coordinating electrostatic interactions and molecular associations. LHAP can effectively solve the settlement instability problem of cement slurry under ultra-high temperature, which is beneficial for improving the safety and quality of cementing construction in ultra-deep wells.

Stone column strategies for mitigating liquefaction-induced uplift of tunnels

Tunnels embedded in liquefiable soil are frequently subjected to uplift and sustain serious damage during major earthquakes. Mitigation methods to prevent the flotation of these tunnels must be developed and implemented in the natural environment. For this purpose, this study proposes a new method that uses stone columns to enhance soil drainage and mitigate soil liquefaction around tunnels. A circular tunnel in liquefied soil is simulated using a 2D finite element model, PLAXIS 2D, and subjected to a sinusoidal input motion. The tunnel's pre-construction and post-construction scenarios are examined. Parametric studies are carried out to investigate the effect of changing several parameters, such as the distance between stone columns and tunnel springing, the diameter of stone columns, the spacing between stone columns, the number of stone column rows, and the stone column arrangement patterns on the effectiveness of liquefaction mitigation. The study reveals that liquefaction mitigation is enhanced by using stone columns closer to tunnel springing, with larger diameters, less spacing, and more rows of stone columns that are arranged in a square pattern. It also emphasizes the importance of timely implementation of stone columns for maximum benefit.

Shallow Foundations and Deep Foundations; Drilled Piers, Aggregate Piers and Stone Columns; Design Recommendations, Construction Considerations, and Performance

Shallow Foundations and Deep Foundations; Drilled Piers, Aggregate Piers and Stone Columns; Design Recommendations, Construction Considerations, and Performance

Numerical Stability Analysis of Sloped Geosynthetic Encased Stone Column Composite Foundation under Embankment Based on Equivalent Method

As an effective technology for the rapid treatment of soft-soil foundations, geosynthetic encased stone column (GESC) composite foundations are commonly used in various embankment engineerings, including those situated on sloped soft foundations. Nevertheless, there is still a scarcity of stability studies for sloped GESC composite foundations. Several 3D numerical models for sloped GESC composite foundations were established using an equivalent method. The influences of the area replacement ratio and the tensile strength of geosynthetic encasement on the stability were investigated. The results showed that the stability increased nonlinearly with the area replacement ratio, and there existed an optimal area replacement ratio (e.g., 24.56% in this study) to balance the safety and economic requirements. The stability increased linearly with the tensile strength of geosynthetic encasement at low tensile strength levels (lower than 105 kN/m in this study), and the impact was relatively limited compared with that of the area replacement ratio. In addition, the stability generally decreased nonlinearly as the foundation slope decreased, and high-angle (foundation slope close to 30°) sloped GESC composite foundations are recommended to be treated with multiple reinforcement techniques. The relationship between the minimum area replacement ratio and the foundation slope was further quantified by an exponential function, allowing for the determination of the area replacement ratio of various sloped GESC composite foundations and providing theoretical guidance for engineering practice.

Optimized Design of Floating Stone Columns for Enhanced Long-term Settlement Performance of Soft Soils

Optimized Design of Floating Stone Columns for Enhanced Long-term Settlement Performance of Soft Soils

Experimental study on the behavior of sandy soil reinforced by stone columns

Experimental study on the behavior of sandy soil reinforced by stone columns

3D Finite Element Analysis of Stone Column Behaviour in Layered Soil with Geosynthetic Reinforced Soil Beds

3D Finite Element Analysis of Stone Column Behaviour in Layered Soil with Geosynthetic Reinforced Soil Beds

A Study of Single Stone Column Bearing Capacity from a Full-Scale Plate Load Test in Long Son Project

A Study of Single Stone Column Bearing Capacity from a Full-Scale Plate Load Test in Long Son Project

Cyclic response of floating geosynthetic-encased steel slag columns in soft clay

Geosynthetic-encased stone column (GESC) technology for strengthening soft clay offers significant advantages in terms of cost-effectiveness, environmental sustainability, and engineering applicability. It is widely applied in treating soft foundations for railways, bridges, and embankments. This study evaluates the cyclic response of the geosynthetic-encased steel slag column (GESSC) composite foundation employing three-dimensional nonlinear finite element analysis. A numerical study is conducted to assess the cyclic response of floating GESSC considering the influence of key design variables, including cyclic load amplitude, loading frequency, geosynthetic encasement stiffness, and length-to-diameter ratio. Results show that both cyclic load amplitude and frequency affect the cumulative settlement and excess pore pressure within the GESSC foundation. Within specified limits, increasing the encasement stiffness and column length can significantly improve the GESSC load-bearing characteristics. The parametric study suggests an optimal geosynthetic encasement stiffness for the field prototype columns within the range of 4480–5760 kN/m and a critical steel slag column length of 10 times the column diameter.

Numerical Simulation of the Load Transfer Mechanism of a Geosynthetic Encased Stone Column Unit Cell under Embankment Loading

Numerical Simulation of the Load Transfer Mechanism of a Geosynthetic Encased Stone Column Unit Cell under Embankment Loading

Consolidation Behaviour of Stone Columns Made with Tyre-Derived Aggregates

Consolidation Behaviour of Stone Columns Made with Tyre-Derived Aggregates