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Reinforced soil has been widely used in civil engineering for various infrastructure applications, including retaining walls, bridge abutments, foundations, support structures for highways, and railways. This study focused on examining the fundamental behavior of mechanically stabilized earth (MSE) walls using numerical modeling technique in the PLAXIS 2D software. The investigation includes the impact of tiered configurations, such as single-tiered, two-tiered, and three-tiered wall systems. Increasing the number of tiers showed lower displacements about 22% and improved stability. The influence of offset distances between tiers is further explored for two-tiered and three-tiered walls. Increase in offset distances showed decrease in displacements about 23% and improved stability by reducing the axial force distribution by 51% in two-tiered walls and 26% in three-tiered walls compared to single-tiered wall. Furthermore, the study investigated the effects of reinforcement stiffness and spacing between reinforcements. Keeping the length of the reinforcement in accordance with load to be applied and based on the findings from these analyses, the geometry of the MSE walls is fixed with the obtained optimum parameters such as offset distance and stiffness of reinforcement for application of different magnitude of surcharge loads. Surcharge loads of more than 200 kN/m resulted in FOS less than 1.5 stating the feasibility of potential failure of even multi-tiered walls with reinforcement of larger stiffness and closer spacing. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of the increasing age of vetiver grass on the factor of safety (FS) of slopes. Data were gathered from previous studies to establish a mathematical relationship between root cohesion—a key factor influencing FS—and the plant's age. Finite element modeling using PLAXIS 2D software was conducted on a 45-degree slope to calculate FS in the absence and presence of vetiver grass at ages 5, 10, 15, and 20 years. Results indicate that root cohesion (cr) and root area ratio (RAR) significantly affect FS values. Over 20 years, soil cohesion increased by 67%, and the FS of a 45-degree slope improved by 6.7%. A constant internal friction angle (K) was considered to create a graph for calculating root cohesion values across different ages with varying K values. Additionally, a simple mathematical model was developed to predict root cohesion based on plant age, considering other critical factors such as RAR. The study also found that while root cohesion increases with age, the rate of increase diminishes over time. Overall, the shear strength of rooted soil enhances with higher RAR and mobilized tensile strength of roots. This research highlights the substantial role of vetiver grass in improving slope stability, providing valuable insights for the application of vetiver in soil conservation and slope stabilization projects. [ABSTRACT FROM AUTHOR]

Abstract In this work, the results of instrumentation over 8 years, including the phases of construction, first impounding, and operation, have been used to analyze the location of the Eyvashan Dam settlement. Mohr–Coulomb behavioral model and numerical model of Plaxis 2D software were used to verify the monitoring results. The results demonstrated that settlement of the dam has increased in the dam's core since the beginning of construction, and they eventually stabilized during the operation phase. After the completion of the construction phase, the maximum settlement of the dam core was recorded as 809 mm, which is equivalent to 1.2% of the height of the dam at the middle level. Also, an approach to interpreting the settlement behavior of earth dams has been presented that is based on spatiotemporal clustering. Also, RF, MARS, and GMDH models were created based on a proposed scenario to predict settlement using points located in a cluster. Therefore, the settlement location of the studied dam was determined using the results of the k-means clustering algorithm in the aforementioned AI models. The high accuracy of the results of the proposed method confirms the proper performance of using AI models in predicting and diagnosing the settlement of earthen dams using the results of k-means spatiotemporal clustering algorithm. The evaluation of the models shows that the ENN model is a more suitable and efficient tool in this field and can be useful in monitoring the settlement of earth dams.

Introduction. Soil reinforcement is widely used in the construction of buildings and structures in complex geological conditions, especially with the help of vertical elements. Calculations of reinforced foundations in practice are carried out by various methods, including numerical methods. Many studies were carried out on soil behaviour during pile reinforcement and its effect on settlement, but the interaction between soils and reinforcing elements is not fully understood. The choice of element location and assessment of the influence of soil liquefaction on the reinforcement efficiency under seismic effects remain topical tasks.Materials and methods. The effects of different reinforcing pile arrangements on the behaviour of the soil mass and foundation settlement under seismic loads are studied. Three pile arrangements, including conventional and alternative arrangements are considered using the PLAXIS 2D programme. Different soil models are also used in the calculation — UBC3D-PLM and HS Small for modelling the bottom and top layer of the soil depending on its characteristics.Results. The results show that all three selected design schemes obtain a significant increase in settlement during earthquake passage. The different pile arrangements significantly affect the deformation and settlement of the foundation slab, as well as the location of soil liquefaction points under seismic loads.Conclusions. By changing the parameters of pile reinforcement, it is possible to control the size and location of liquefaction zones and, if necessary, to protect some zones from the realization of this process. The presented results can contribute to the design and development of effective methods of construction in earthquake-prone areas.

Large-diameter bored piles can safely transmit loads from structures by skin friction to the surrounding soil strata and end bearing at the bedrock layer, thereby providing a high compressive capacity. High-Strain Dynamic Testing (HSDT) provides a unique alternative technique to traditional Static Load Testing (SLT) for determining the static compressive resistance of the bored piles, considering its quicker performance and significant cost reductions. This article's main objective is to numerically explore the performance of large-diameter bored piles during the HSDT and to understand their dynamic behavior under an axial compressive impact force. This research is based on testing pile foundations for reinforced concrete mixed-use towers in the coastal zone of New Alamein City, Egypt. The tested pile is a 1.20 m diameter bored pile. Numerical modeling is performed to simulate both the HSDT and the SLT for two piles at the same site. Non-linear axisymmetric finite element modeling is employed to validate both test records and develop some sort of matching between the two tests. As lumped models, the developed numerical models use the signal-matching process, which is conducted by varying and adopting the strength parameters and deformation characteristics of the ground or soil deposit and the soil–pile interface. The predicted load-displacement curves, developed from analyzing dynamic records employing the Modified Unloading Point (MUP) method, are consistent with the field records. The verified non-linear models are utilized to accomplish a comparative parametric analysis to better understand the drop-mass system aspects. The analysis results emphasize the significance of employing adequate impact energy (i.e., dropping height and mass) to move the pile top to a sufficient extent to mobilize its full resistance. However, a longer impact duration, i.e., larger mass, is more effective for achieving a deeper high-strain wave. The impact load should be developed by a larger drop mass with a lower drop height, not a smaller drop mass with a higher drop height. The results also indicate that, for relatively longer piles, the skin friction of the upper layers surrounding the pile shaft is fully mobilized, whereas the skin resistance of the lower layers is not fully mobilized, regarding the stress wave phenomenon effect. Finally, this study's findings can be employed to develop guidelines and design procedures for the HSDT to be effectively performed on bored piles. [ABSTRACT FROM AUTHOR]

The Sumedang-Cirebon Km 68+750 road section is a national road and an important transportation infrastructure in West Java. Albeit the road section's slope has previously been strengthened with bored pile reinforcement, the slope continues to move. This study's objective is to examine slope stability by considering earthquake loads and to suggest improvements for efficient slope reinforcement. Slope stability analysis utilizing PLAXIS 2D program based on the finite element method and DMT-KD Method which is the result of field testing using the Flat Dilatometer Test (DMT)). PLAXIS modeling results show that the slope failure line is deeper below the bored pile reinforcement. The results of the analysis using DMT-KD method showed similar slope failure, the conclusion is DMT-KD method can be the initial basis for slope stability analysis on mudstone. The PLAXIS modeling results obtained a static safety factor of 1.113 and a safety factor due to an earthquake of

Rapid urbanization in India, particularly in Kolkata, has led to a scarcity of suitable land, necessitating effective ground improvement techniques. A case study was evaluated using 500mm diameter, 10m long plain cement concrete (PCC) piles installed at 2m c/c spacing to enhance subsoil for a high-rise residential structure. Initial Dilatometer (DMT) tests showed the subsoil was unsuitable for shallow foundations. Post-PCC piling, DMT tests revealed a 30-40% improvement in subsoil stiffness. The factor of Safety against liquefaction was calculated using DEEPSOIL software. Further analyses with DMT Settlement software and PLAXIS 2D confirmed that post-piling, the raft foundation settlement remained within permissible limits, proving the effectiveness of the ground improvement measures. [ABSTRACT FROM AUTHOR]

This study systematically examines the behavior of cantilever and anchorage sheet piles influenced by a range of variables, namely dredge level, water table level, anchor interanchor distance, anchors’ number, and the distance from the ground surface. Utilizing a single sheet pile material, the investigation highlights the deformations resulting from these variables, in addition to assessing the effects of different soil types and degrees of saturation. The primary objective centers on the computation of bending moments arising from these factor variations under a constant load, using the finite element theory-based software, Plaxis 2D Connect Edition V20. Sheet pile behavior could be evaluated using this tool by investigating driven depth, maximum bending moments, and horizontal displacements in both anchorage and cantilever sheet piles. To enhance the reliability and realism of findings, outcomes are compared with results from the Pro Sheet program. This comprehensive evaluation furnishes valuable insights into sheet pile deformations under diverse conditions, contributing to the existing body of knowledge and facilitating more robust engineering practices. [ABSTRACT FROM AUTHOR]

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Over the past few years, the weight of goods that are transported on roads in Egypt has rapidly increased. Engineers have developed safe methods for building roads on soft soils as a result of a growing need for improvement. But Highway pavement design on soft clay soil is still a very difficult problem to solve. It frequently results in issues like unstable roadbeds or excessive settlement. As a result, treating soft soil roadbeds has gained importance. To support the appropriate pavement portion and its traffic loads, this study intends to improve the clay soil using various techniques. In this study, quicklime is used to stabilize soft clay soil. geogrid layers are also used to strengthen the base and subbase layers which increases the overall strength of the pavement section to sustain heavy loads above. A finite element program (PLAXIS 2D) was used to simulate these improvement techniques to identify the best solutions for the problem. Results showed that improving a 60 cm layer of subgrade soil with quicklime combined with adding a geogrid layer in the middle of the subbase layer gives the best results.

Non-pressure filtration flows with a free surface, on which the fluid pressure is a constant and equal to the external atmospheric pressure, are essential characteristic of groundwater filtration through such hydraulic structures as, dams, water drawdowns, drains, foundations, and pits during their drain. The problems of fluid filtration in porous media are distinguished by a variety of boundary conditions for the desired complex filtration potential, geometric and physical characteristics of the filtration flow. Solving such problems by analytical methods becomes significantly more complicated due to the nonlinearity of the equation describing the filtration movement, the presence of a free surface and the geometry of the slopes of the structure. An alternative to their solution is the use of numerical methods for estimating unsteady free-flow filtration flows. This research is dedicated to developing a hydrodynamic analysis approach of the process of unsteady filtration by the methods of computational fluid dynamics on the example of a rectangular cofferdam of various configurations to apply the results in the design of hydraulic structures. Numerical modeling of an unsteady free-flow filtration in a rectangular cofferdam using the finite volume URANS method (ANSYS FLUENT) and finite-element method (PLAXIS 2D) was carried out. The depression curve evolution through time was obtained. Also, numerical results have been compared both with the experimental results and classical theoretical assumptions. Was found that the constructed models both for finite-volume and finite-element methods are consistent enough with the experimental data, and on the other hand, theoretical assumptions don’t agree with experimental and numerical data. Further, the filtration patterns in rectangular cofferdams with different drain positions were obtained using the developed calculation model, which allows to choose the most effective drain position for different purposes.

B ack stability analysis, in-lab testing, and field tests may all be used to assess the behavior of stability of slopes. Each of these approaches has benefits and drawbacks compared to one another. Amongst these approaches, laboratory modeling stands out with its ability to prepare identical samples, keep external conditions under control, and measure deformations precisely. In this study, laboratory-based slope models at 1(Horizontal)/1(Vertical), 2/3, and 1/3 angles including the effects of precipitation and external loading were created. The results of these models were compared with those of the Plaxis 2D software. First, models were built using highly permeable cohesionless coarse-grained soils, and mixtures containing high plasticity clay (bentonite) at different rates were then prepared to investigate the effect of fine-grained soils on stability. Laboratory tests such as sieve analysis, specific gravity, consistency limits, Standard Proctor, and direct shear were used to assess the geotechnical index and mechanical properties of soils. Incremental surcharge loads were placed on the slope models and surface deformations, and local and general collapses under the effect of precipitation were observed. Laboratory model results highlighted that the fines content had a non-negligible effect on stability. When the slope behaviors were examined, it was observed that the models with a 1/3 slope had more severe local fractures and collapses. The stability of the slope is negatively affected when bentonite content in soil mixtures rises. The results of Plaxis 2D analysis are compatible with those of laboratory model tests and the factor of safety values obtained from Plaxis 2D range from 0.98 to 11.4. [ABSTRACT FROM AUTHOR]

One of the methods of soil improvement in the case of highway embankments is to perform pre-loading to increase the shear strength of the subgrade. In this study, the embankment case is modeled in PLAXIS 2D software. The analysis will be conducted under short-term, long-term embankment conditions, services, and pseudostatic earthquakes. The study was conducted by modeling the subgrade using the effective stress analysis (ESA) approach with two different drainage types, Undrained A and Undrained B. In the model with Undrained A drainage type, the long-term stability analysis was performed by modeling consolidation, while the long-term analysis with Undrained B drainage type was performed by updating the undrained shear strength of the subgrade based on the equation by Han (2015). The analysis results show that the factor of safety values of Undrained drainage type A are about 10-28% greater than those of Undrained drainage type B throughout the preloading, service, and earthquake conditions. The difference in the factor of safety values occurs due to differences in the definition of safety factor and failure criterion. Stability analysis with Undrained A drainage type needs to be conducted carefully by considering the accuracy of the long-term parameters, while the accuracy of stability analysis with Undrained B can be improved by calibrating the coefficients in Han, Jie (2015) equation based on the undrained friction angle obtained from the CU triaxial test. [ABSTRACT FROM AUTHOR]

The dynamic response of the retaining structures is a complex issue, and a major challenge in their design, especially under seismic loading conditions. So a reliable and efficient solution following a computational approach, closer to reality, is required to obtain satisfactory results. Hence, this study came to clarify the effectiveness of the PLAXIS 3D program in predicting the performance, accuracy, and reliability of retaining walls. A case study of placing compressed materials as the backfill of the retaining wall soil is analyzed in this study using PLAXIS 3D software. The results are compared with the experimental results and the results of PLAXIS 2D software. The purpose is to predict the performance of retaining walls under seismic loads. As a result, the research stated that the displacement with time was less than the results recorded depending on the program PLAXIS 2D. According to the comparison of the different analytical tools, the researchers concluded that the adoption of the PLAXIS 3D program gives results that are closer to reality, more accurate, and more reliable.

Large-diameter bored piles can safely transmit loads from structures by skin friction to the surrounding soil strata and end bearing at the bedrock layer, thereby providing a high compressive capacity. High-Strain Dynamic Testing (HSDT) provides a unique alternative technique to traditional Static Load Testing (SLT) for determining the static compressive resistance of the bored piles, considering its quicker performance and significant cost reductions. This article’s main objective is to numerically explore the performance of large-diameter bored piles during the HSDT and to understand their dynamic behavior under an axial compressive impact force. This research is based on testing pile foundations for reinforced concrete mixed-use towers in the coastal zone of New Alamein City, Egypt. The tested pile is a 1.20 m diameter bored pile. Numerical modeling is performed to simulate both the HSDT and the SLT for two piles at the same site. Non-linear axisymmetric finite element modeling is employed to validate both test records and develop some sort of matching between the two tests. As lumped models, the developed numerical models use the signal-matching process, which is conducted by varying and adopting the strength parameters and deformation characteristics of the ground or soil deposit and the soil–pile interface. The predicted load-displacement curves, developed from analyzing dynamic records employing the Modified Unloading Point (MUP) method, are consistent with the field records. The verified non-linear models are utilized to accomplish a comparative parametric analysis to better understand the drop-mass system aspects. The analysis results emphasize the significance of employing adequate impact energy (i.e., dropping height and mass) to move the pile top to a sufficient extent to mobilize its full resistance. However, a longer impact duration, i.e., larger mass, is more effective for achieving a deeper high-strain wave. The impact load should be developed by a larger drop mass with a lower drop height, not a smaller drop mass with a higher drop height. The results also indicate that, for relatively longer piles, the skin friction of the upper layers surrounding the pile shaft is fully mobilized, whereas the skin resistance of the lower layers is not fully mobilized, regarding the stress wave phenomenon effect. Finally, this study’s findings can be employed to develop guidelines and design procedures for the HSDT to be effectively performed on bored piles.

To carry out construction on soft soil, cases of land subsidence are often encountered. This is due to the low bearing capacity and small shear force, large compression, and very small permeability. To address this problem, one method that can be implemented is soil improvement using preloading and Prefabricated Vertical Drain (PVD). The aim of this research is to find out the magnitude of consolidation settlement by using analytical methods and by using PLAXIS 2D modeling at reclamation project locations besides CPO tanks between Belawan Islands based on Bore Log BH-02 data. It is also to compare coarse mesh, medium mesh, and fine mesh in PLAXIS 2D modeling, and to obtain the amount of land subsidence using preloading only and preloading with a combination of preloading and Prefabricated Vertical Drain (PVD) based on Bore Log BH02 points. From the analytical results obtained a decrease of 1.254 meters. While the PLAXIS 2D modeling uses a medium mesh that has been combined with a PVD of 1.268 meters. This means that the results of the settlement by modeling using PLAXIS 2D are closer to the SP-02 settlement plate data of 1.270 meters. The settlement uses PLAXIS 2D with a coarse mesh of 1,266 meters and a fine mesh of 1,282 meters. While modeling using preloading only obtained a decrease of 0.340 meters. It can be concluded that the results of modeling using PLAXIS 2D in using medium mesh that has been combined with PVD are relatively closer to settlement data in the field with a percentage difference of 0.142% settlement plate SP-02 settlement. [ABSTRACT FROM AUTHOR]

In the planning of civil building, construction problems are often encountered in soft soil types, including low soil carrying capacity and large settlements (settlements) when given a load. Soil improvement is needed to speed up the consolidation settlement time. One method that can be applied to speed up the consolidation settlement time is to use a pre-fabricated vertical drain (PVD) and this preloading method is able to increase the shear strength of soft soils and remove pore water in the soil. This research aims to determine the magnitude of settlement of soft soil consolidation using the 1-dimensional Terzaghi consolidation formula and analysis using the finite element method with PLAXIS 2D modeling, comparing the results of PLAXIS 2D modeling with actual data, the effect of the smear zone effect on the settlement of soil consolidation in the embankment area and to determine the difference in the decrease in preloading methods combined with PVD and preloading without PVD based on point bore log BH-1. From the results of the analysis, it is found that the consolidation settlement by analytical method using the 1- dimensional Terzaghi consolidation formula was 0.858 meters. The amount of settlement that occurs in the consolidation process using PLAXIS 2D modeling taking into account the smear zone effect is 0.786 meters and 0.852 meters without taking into account the smear zone effect. Meanwhile, the actual settlement that occurred in the field based on settlement plate (SP-01) was 0.867 meters and the magnitude of the preloading settlement without PVD was 0.512 meters. It can be concluded that the PVD combination preloading method is proven to accelerate consolidation time, while the improvement with the preloading method alone produces a relatively small decrease. [ABSTRACT FROM AUTHOR]

Modeling the surface element and support system in deep excavation pits and investigating the deformation mechanism is an important issue. In this study, alternative solution methods for an anchored bored pile model are compared and discussed, and it is aimed to contribute to the studies to be carried out in the deep excavation area. A numerical analysis of retaining wall design is examined in the case of the Sivas cultural center building's deep excavation using Plaxis 2D and GGU-Retain software. Measured field data and simulated results are discussed. As a result, the bending moment and lateral deformation reach a maximum when the foundation pit is excavated to the bottom. It can be said that the lateral deformation value found with Plaxis 2D is within the allowable limits, closer to the field data, and provides sufficient quality. The research results will provide theoretical and practical knowledge for designing and constructing similar deep excavation pits for the optimal strategy. [ABSTRACT FROM AUTHOR]

In soil engineering, the soil slope is one of the important issues in geotechnical and environmental engineering that can fail due to settlement behaviour. Due to soil slope instability, roads near the Segamat River's slopes have seen severe settlement. Therefore, this study was carried out to determine how the geometry of the soil slope and the properties of the soil affect soil stability and deformation. Because of the varying slope geometries along the river, this study used two alternative slope geometries in its modelling. A comparison was made between the existing slope and the slope stabilised with sheet piling by using Plaxis 2D. Other parameters that affect slope stability are also being investigated, such as anchor length and anchor installation angle. The anchor sheet pile's presence is intended to improve the slope's stability. As a result of this analysis using PLAXIS 2D software, the optimal anchor length depends on the passive pressure of the soil behind the sheet pile. According to the results, installing an anchor with a 60° angle is more stable because the safety factor obtained is 3.26 which is greater than that of a 45° angle which is 1.33. It shows the anchor is the best support of the sheet pile for the soil slope stability. [ABSTRACT FROM AUTHOR]

The fatality of a slope failure is devastating; slope stabilization methods are adopted to prevent such an incident. Nailing is known as one of the most used methods of slope stabilization. This research study has been conducted to observe the increment of stability of natural slopes by the nailing method. Here, bamboo is selected as an eco-friendly material for nailing. The stability analysis of slopes is conducted by numerical analysis. Finite element analysis is performed with PLAXIS 2D. The soft Soil model and Mohr-Coulomb model are used to define soil parameters. A comparison of these two soil models is also a concern of this study. The slope is modeled according to the natural slope. The stability analysis is conducted for five slope angles: 20⁰, 25⁰, 30⁰, 35⁰, and 40⁰. It is observed that the increase in slope angle factor of safety (FOS) decreases. Inserting nailing material as soil reinforcement increases the stability of the steeper slopes. Mild slopes usually remain stable in bare conditions; however, nailing improves that stability. Increased stability is observed more in this study for steep slopes. After nailing, the factor of safety increases by up to 21% for 20-30 degree slopes and up to 36 % for 30-40 degree slopes. It is expected that professional engineers will find this paper helpful while treating a slope with the nailing method.

Soil reinforcement is a modern and specialized soil improvement field. It includes a variety of procedures involving the placement of inclusions in soil. The majority of research has been conducted without respect to the fundamental features of reinforced soil on the behavior of foundations sitting on reinforced soil. As a result, this study provides an laboratory study of the mechanical and compressibility characteristics of a specimen of reinforced silty clay at a medium depth using an environment friendly jute cloth Geotextile (JGT). In addition, the article investigated using finite element computer software the impact of JGT reinforcement on a foundation's carrying capacity resting on silty clay utilizing the finite element computer program Plaxis 2D. Reinforcement's impact on shear failure and shear stress were investigated. The results demonstrate that the addition of such reinforcement enhances the shear strength of the reinforced samples, lowers compressibility and therefore increasing the bearing capacity of reinforced soil under foundations.