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Vocal cords play an important role in human speech production. The development of mechanical models of vocal cords has increased the understanding of their role and functionality. Numerous numerical studies have been explored to investigate the properties of vocal cord. In this work, one-mass mechanical model of vocal cord has been identified to be solved numerically using B-spline collocation method. Parameters of the model have been extracted from 25 years old male and female voices. Displacement of vocal cord at time, t, have been generated explore for each voice. The number of phases and highest displacement have also been discovered in the finding. Duration of first phase of each voice has also been explored. [ABSTRACT FROM AUTHOR]

Vocal cords play a crucial role in human speech production. The development of mechanical models of vocal cords has increased the understanding of their role and functionality. Numerous numerical studies have been explored to investigate the properties of vocal cord. In this work, one-mass mechanical model of vocal cord has been identified to be solved numerically using B-spline collocation method. Parameters of the model have been extracted from real voices data classified as normal and pathological voices. New results, displacement of vocal cord at time, t, have been generated for each voice. The findings indicated that each voice produced a different value of displacement due to the damping and subglottal pressure of each voice. The number of phases and highest peaks displacement have also been discovered in the finding. [ABSTRACT FROM AUTHOR]

The electrical output of solar absorbers like monocrystalline photovoltaic (PV) panels besides the solar irradiance, heavily rely on the operating temperature within the environment. This work investigates an innovative cooling technique to mitigate the detrimental impact of temperature rise on PV panel performance, especially in a temperate region. Nanocoolants have higher thermal conductivity than conventional fluid, hence the effect of its good thermal properties was investigated to observe its influence on the electrical performance of the PV panels. The work involved numerical analysis using the commercial code ANSYS. The Multiphysics approach begins with the steady state analysis and then CFD to observe the thermal flow behaviours of the different components making the panels. The simulation considered three different PV arrangements, the uncooled, the nano-cooled and the water-cooled panels. The panel's surface was exposed to solar irradiance of 650 W/m2 and the operating temperature of 40°. The result found that Al2O3-water nanofluid as a cooling agent by spraying on the solar panel module at the velocity of 0.01m/s can decrease the temperature of the solar panel from 73.85 °C to 35.95 °C. Hence utilization of Nanocoolant for cooling of PV has a good potential in electrical performance enhancement. [ABSTRACT FROM AUTHOR]

Material extrusion based fused deposition modeling (FDM) is important type of additive manufacturing (AM) technologies. This study focuses on numerical analysis and multi-objective optimization of FDM process parameters for the manufacturing of micro-turbo machinery impellers. A three dimensional model of impeller is converted into Standard Tessellation Language (STL) format and separate G-code file is generated for each specimen with consideration of two important process parameters, layer thickness and infill density. FDM process is simulated with numerical simulation tool Digimat-AM software to predict the responses residual stress, deflection, material consumption and printing time. Results of the simulation is analysed with response surface methodology (RSM) to predict the relationship between process parameters and responses. Analysis of variance (ANOVA) is utilised to validate the significance of developed model and identify significant process parameters and its interactions. Further, optimal setting of process parameters is identified with response optimizer tool as 0.321798 mm layer thickness and 20% infill density. The corresponding optimum response values indicated residual stress 36.8074 Mpa, deflection 0.518879 mm, material consumption 13.3117 g, and printing time 60 min. Significant impact of layer thickness and infill density is observed on residual stress, deflection, material consumption and printing time. These findings can be used to optimize the FDM process for manufacturing of high precision parts. [ABSTRACT FROM AUTHOR]

Wind load analysis is a critical component of tall building design, ensuring structural integrity and safety. This study investigates the wind load analysis of a specific 14-story building, employing numerical methods to assess its impact on structural design and implications for stability. Adhering to the guidelines outlined in the Australian building code, the research utilizes STAAD Pro software for numerical analysis. Through a thorough examination of wind-induced stresses and deformations, the paper offers insights into the factors influencing structural integrity and suggests potential design modifications and mitigation strategies. The findings from this study suggests that it's not always needed to focus so much on wind when designing buildings. However, careful consideration needs to be given to design changes, especially as buildings get taller. It was also observed that sometimes, the problems caused by the shape of the building can be more important than worrying about the wind. [ABSTRACT FROM AUTHOR]

In this paper, numerical analysis of reinforced concrete beams with web openings enhanced by reactive powder concrete layer was accomplished at different locations. The advantages of using RPC materials with RC beam depend on the location of RPC layers in tension zoon (bottom of web openings) or compression zoon (top of web openings). So, this numerical study aims to verify the behavior of twelve experimental RC-RPC composite beams using normal strength concrete with RPC to obtain optimal advantages. The main variables have studied the effect of the location of the RPC layers and the number of web openings on the strength of beams. By verifying the ANSYS result comparison with experimental results of beams, the mean accuracy is about 1.146, and the standard deviation is about 0.043. Numerical results showed that the final strength decreases with an increasing number of openings. It was found that the use of RPC layers effectively improved the performance of the beams compared to ordinary concrete layers. The ultimate strength of RC-RPC composite beams was increased about 1.5, 1.5 and 1.3 time by using RPC layers in the compression and tension regions compared with the identical normal concrete beams with one, two and three openings, respectively. Meanwhile, the optimum location of the RPC layer is determined at tension zoon RC-RPC composite beams. Finally, crack patterns of NC-RPC beams depend on the number and location of transverse openings, which determines the onset of cracks and the type of failure. [ABSTRACT FROM AUTHOR]

Due to the excess use of air conditioning systems led to significantly increase the demand for electric power in the household sector. Therefore, to decrease energy consumption, it can use an Earth-Air Heat Exchanger (EAHE); it has been demonstrated to be promising method for heating and cooling applications. In this paper, simulation study was performed using ANSYS FLUENT 19.0 (CFD) program as a numerical analysis on the impact of different pipe shape and air velocity on the performance according to the climatic conditions of Baghdad-Iraq in the summer and winter seasons. The pipes shapes in EAHE system that were used are spiral, wave and straight at the same length and diameter, and it has been studied their impact on performance at different speeds (5, 10 and 15 m / s). The results of numerical analysis showed that the shape of pipes and velocity of inlet air have an effect for the temperature of outlet air and performance of EAHE. Through the results obtained, it was found that the shape of straight tube presents the best performance compared to the other two shapes of spiral and wave. Therefore, the better performance for EAHE can be achieved on operating the system at low air velocity together with straight shape for the exchanger pipe. [ABSTRACT FROM AUTHOR]

Artificial lateral boundary is important in the numerical simulation of seismic responses of underground structures. In this paper, the performance of three commonly artificial lateral boundaries (i.e., tied boundary, fixed boundary and roller boundary) are compared based the nonlinear finite element simulation of an underground structure-soil system. The accuracy of the three artificial boundaries is discussed in terms of structural racking deformation and acceleration responses. For each artificial boundary, the influence of distance away from underground structure is discussed. The results show that when the distance from the edge of the structure to the lateral artificial boundary is more than 9 times its own width, the simulation errors of all kinds of artificial boundary are less than 5%. Among the three types of artificial boundaries, the calculation accuracy of roller boundary is best. Its distance is 3 times the width of the structure, which can satisfy the calculation error of both the structural acceleration response and the inter-story drift response within 5%. [ABSTRACT FROM AUTHOR]

This paper studies a new hybrid conjugate gradient (CG) method based on the Aini-Rivaie-Mustafa (ARM) CG method for solving nonlinear unconstrained optimization problems. The new hybrid method eliminates the negative values generated by the ARM method in its CG coefficient by replacing those values with a positive CG coefficient. The numerical test was conducted on 10 standard test functions from small to large scale under inexact line search. Based on the numerical results, the method proved to be more efficient compared with some older versions of CG method in terms of number of iteration and CPU time. In addition, a set of data for number of road accidents was collected from Portal Rasmi Polis Diraja Malaysia. By using discrete least squares method of numerical analysis and CG method in unconstrained optimization, the data can be estimated. Results from the error calculation for both methods showed that the proposed CG method is comparable with the least squares method. [ABSTRACT FROM AUTHOR]

In recent times, there has been an increasing interest in the study of B-spline functions. This interest stems from the attractive properties of these splines, including their local control and flexibility. The present study aims to address the scientific gap of Cubic B-spline Collocation Method (CBCM) in Numerical Analysis. The current developments and potential applications of CBCM, which can be extended to higher orders in more complex problems are explored and discussed in this study. A systematic review of the existing literature is conducted, and the following three aspects are addressed: (1) the application of conventional CBCM; (2) the advantages and disadvantages of CBCM, including the accuracy, stability, and convergence of the scheme; and (3) the potential extension of CBCM. In conclusion, this paper provides valuable insights into CBCM, thus paving the way for the improvement of its applications in Numerical Analysis. [ABSTRACT FROM AUTHOR]

Cold-formed steel product sections are abundantly utilized in the metal buildings, constructions and Industries for more than four decades. These products are found more in general in every form of working environment due to their flexibility, availability, market value, increased weight and strength ratio, easy fabrication and so on. The highly notable application is that these steel sections are obtainable in varied shapes that we can avail predominantly according to the need. The finite element method is specifically technique of numerical analysis to pertain mere elucidations to massive range of engineering crisis. This paper depicts an analysis by numerical method with bending operation of cold-formed steel built-up sections. The results obtained through the experiment are conformed through finite element analysis with ANSYS R2 Software and Manual designs. The investigational results procured are better submission to the analytical outcome. [ABSTRACT FROM AUTHOR]

The primary goal of the proposed article is the numerical analysis of the Wing model with and without raked winglets. In order to highlight the significant performance and parameter variations between the designs, the investigation here analyses the parameters of wings made with and without serrated raked winglets. Here, the lift-to-drag ratio, lift coefficient, and drag coefficient were the main topics of conversation. This study's tapered wing design was based on the NACA 653-218 air foil. The geometry of the models is implemented and developed using the Solid Works programme. The main objectives of this work are to enhance flight performance by reducing the induced drag that is produced on the wings during action using ANSYS Fluent. It is found that the Serrated Raked Winglet (SRW) gives better reduction in drag and turbulence than the existing normal raked winglet without affecting its lift more at higher angle of attack. [ABSTRACT FROM AUTHOR]

The study is concentrate on the numerical investigation of water thermal stratification in the discharge mode storage tank. The high efficiency of thermal stratification can significantly increase the overall performance of solar heating system. The proportion of the water tank in this study is of a dimensions 0.4, 0.4 and 0.8 meters. The aim of the present study is for increasing the stratification efficiency by inserting different baffle shapes in the tank bottom near the cold flow inlet. It is quantitatively analyzed at a 60°C starting temperature, a 20°C input temperature, and flow rates of (8 l/min). The inlets included a flat, inclined, and curved baffle. The purpose of the baffles is for reducing turbulence mixing to enhance the thermal stratification efficiency. Fluent 14.0, a three-dimensional (3D) Computational Fluid Dynamics (CFD) simulation tool, was used to expose the unique concepts based on factual-world operating conditions and storage tank design. Other mixing and stratification evaluation methods were used to determine the degree of stratification, such as the stratified and Richardson numbers. The results show that the shape and location of the baffle increases Richardson's and Stratification's Number compared with standard storage tank type, and the best stratification efficiency is in the A1 tank by around 48%. [ABSTRACT FROM AUTHOR]

The present study aimed to design a subsonic wind tunnel and compare the numerical and experimental results to ensure the accuracy of the design that has been manufactured after the simulation process. The Euler equations of the two-dimensional inviscid flow were solved using a finite volume approach by utilizing an algorithm developed in MATLAB. The values of velocity in the x direction (u), velocity in the y direction (v), static and stagnation pressure, and density of the flow were computed at each point of a (100 X 32) mesh with a time step of 0.002 X 10−7 for 1000 iterations. The mass flow rate FMR value of one, the uniformity of the flow in the test section, which is obvious in the fluid properties contours, the pressure value of 105 N/m2 that has been constant at inlet and outlet, and the good agreement of numerical and experimental results between pressure and velocity variations along the centerline of the subsonic wind tunnel are all indicators of the accuracy and computation efficiency of the analysis method that has been used. [ABSTRACT FROM AUTHOR]

Fractional calculus can be considered as rapidly developing research area widening limits of traditional computing. Current study is focused on development of numerical methods for solving fractional order differential equations using Haar wavelet methods. There are two Haar wavelet based approaches available in literature for solving fractional order differential equations. These two approaches are analyzed. Furthermore, the refined wavelet expansion is proposed in the case where the order of fractional derivative is less than one. The theoretical approach introduced is validated by numerical analysis. [ABSTRACT FROM AUTHOR]

Culture of living cells using scaffolds and bioreactors to mimic the natural environment of native tissue as close and possible allows to better understand the mechano-biological parameters involved. In this context, the architecture of biodegradable scaffolds contributes to control some of these key parameters such as permeability and fluid flow-induced shear stress. However, these studies are very time-consuming and costly. As a complement to in vitro research on the influence of these parameters, the use of numerical models plays here a key role to predict the mechano-biological outcomes. In this study, the effect of biodegradable scaffold's architecture on the above-mentioned parameters was computationally investigated. For this purpose, eight orthogonal and non-orthogonal scaffolds including graded and non-graded porous models under dynamic cell culture conditions were explored. The results suggest 60GRAD geometry as the best candidate for bone tissue engineering. The findings of this work can be used to design better biodegradable scaffolds in this research field. [ABSTRACT FROM AUTHOR]

The document is a preface to the Proceedings of the International Conference on Numerical Analysis and Applied Mathematics 2022 (ICNAAM-2022). The conference aims to bring together leading scientists in the field of Numerical and Applied Mathematics and attract high-quality research papers. The selection of papers included in the volume was based on an international peer review process. The preface expresses gratitude to the Scientific Committee, organizers, invited speakers, and others involved in the conference. It also mentions the inclusion of the Proceedings in the AIP Conference Proceedings series. The document provides information about the conference details, the European Society of Computational Methods in Sciences and Engineering (ESCMSE), and the categories of membership in the society. [Extracted from the article]

There are several researchers have examined laminated bamboo beams. The outcomes revealed that laminated bamboo beams had high flexural strength but low elastic modulus. The low modulus of elasticity causes the beam to have low stiffness so that the high flexural strength cannot be utilized optimally. This study seeks to analyze the increasing amount of beam stiffness by adding CFRP along the tensile and or compressive sections of the beam. To get the result, a numerical simulation was carried out on laminated bamboo beams with a cross-sectional of 50 mm in width, 50 mm in height, and a span length of 1,400 mm. There are three groups of beam treatment, the name given for CFRP in both tension and compression zones, in the compression zone, and in the tension zone. The length of CFRP for the three treatments is the same as the span of the beam. The results of the numerical analysis showed that the beam with the addition of CFRP experienced a significant increase in stiffness. Compared to the stiffness of the beam without CFRP, the beam with the addition of CFRP in both the tension and compression zones, in the compression zone, and the tension zone, experienced an increase in stiffness of 66.21%, 51.19%, and 15.89%, respectively. The model of damage to the beam is divided into flexural damage and shear damage. The simulation results indicate that the beam with the accumulation of CFRP in both tension and compression zones encountered flexural damage and shear damage; the beam with the addition of CFRP in the compression zone underwent flexural damage, and the beam with the addition of CFRP in the tensile zone experienced flexural damage and shear damage. [ABSTRACT FROM AUTHOR]

In comparison to single-rotor wind turbines, dual-rotor wind turbines have recently been designed to increase wind capture and power generation. However, in low wind speed areas with average wind speeds of less than 4 m/s, the wind turbine struggles to function and operate at its best. In this paper, different dual rotor wind turbine geometries are designed and simulated using computational fluids dynamic software and optimized using response surface methodology to compare the performance of the wind turbine. The main objective is to investigate the effect of different blade materials on different wind speeds to the performance of the wind turbine by using ANSYS WORKBENCH R2 and choose the best blade material for the wind turbine by using Design Expert 13. Wind turbines have been analyzed at a different wind speeds of 2 m/s, 3m/s and 4 m/s. Three different blade materials are compared to the force performance in this study. The wind turbine performance was also investigated numerically. In this research work, lift force and drag force are the parameter that determines the thermal performance of the heat sinks. The findings revealed dual rotor wind turbine with carbon fiber blade was the best to be used in low wind speed areas. [ABSTRACT FROM AUTHOR]

In this paper, the population was divided into seven subpopulations, namely susceptible (S), vaccination (V), exposed (L), infected not reported (I1), infected reported (I2), quarantine (Q) and recovered (R) subpopulations. Analytical study on the COVID-19 model, to determine the non-endemic equilibrium point, reproduction number, and system stability. The model solution was determined by numerical analysis, and model sensitivity analysis by changing the values of the vaccination rate and treatment rate parameters. Based on numerical simulation results, if the value of the vaccination parameter or the value of the treatment parameter increases, the number of individuals in the subpopulation infected with COVID-19 decreases, and the number of individuals recovered from the subpopulation increases. [ABSTRACT FROM AUTHOR]

The benefits of third generation hybrid organic-inorganic metal-halide Perovskite Solar cells (PSC), makes it the potential candidate among all solar cells, but challenges on improving stability of the Perovskite solar cell makes it the secondary option compared to the conventional solar cells. In this paper, simulation work on the stability intended combinations of ideal layers such as HTL (CuSCN) / ETL (SnO2) along with the absorber layers CH3NH3MAPb (I 1-xCl x)3, FAPbI3and Rb0.5 Cs0.1 FA 0.85 Pb I3are conceded. Here, the thermal variations are being investigated and the study reveals that as temperature increases from 250K to 450K the efficiency of FAPbI3 based PSC falls from 21.7% to 11.1% andfrom 20.1% to 13.9% for Rb0.5 Cs0.1 FA 0.85 PbI3based PSC and from 20.8% to 14.2% for MAPb(I 1-xCl x)3based PSC. The simulation work also shows that the proposed structure with charge transport layers ETL (SnO2),HTL (CuSCN) and active layer MAPb (I 1-xCl x) 3has the potential for improving thermal stability. [ABSTRACT FROM AUTHOR]

Mitigation of total pressure loss and improvement in aerodynamic performance are obtained on a low aspect ratio turbine blade. The turbine blade hub region is constructed with a boundary layer fence to reduce secondary losses. The major objective of implementing boundary layer fence is to restrict the pressure side leg of horseshoe vortex from reaching suction surface of adjacent blade. This decreases the loss associated with the passage vortex by delaying its development. Present analysis reveals the aerodynamic performance of boundary layer fence in three ways. Firstly a rectangular strip is kept close to the suction surface in order to break the suction side leg of horseshoe vortex. Secondly, to restrict the pressure side leg of horseshoe vortex from traversing from pressure surface to suction surface a fence of curved trailing edge is kept at the middle of the blade passage. In the third configuration the combined effects of both rectangular strip and fence have been analyzed. In this work the shape of the rectangular strip and fence do not follow the blade profile. Ansys-cfx, commercial software is used for numerical analysis. The results indicate that the presence of strip has resulted in the breakdown of suction side leg of horseshoe vortex and the location of fence has directed the pressure side leg of horseshoe vortex more axially rather than traversing across the blade passage. The combination of both geometries has achieved further reduction of total pressure loss coefficient. [ABSTRACT FROM AUTHOR]

This study investigated the influence of press-fitting on the stress concentration and fatigue life of axles. Models of finite element analysis (FEA) with and without the press-fitting effect were developed using Abaqus software. These models were used to analyze the axle strength and profile the stress histories under various loads and running conditions, such as bending load, wheel-rail contact force, lateral force, and press-fitting force. Their combined loads were responsible for the axle fracture. Also, the prediction of fatigue life was extended to a three-dimensional stress state under fully reversed cyclic loading and variable overload spectra using commercial Fe-safe software with a strain-based Brown-Miller Morrow fatigue algorithm. With the press-fitting effect, the maximum von Mises stress at the groove notch transition zone of the axle was 6% higher than without the press-fitting effect. Press-fitting reduced the fatigue life of an axle by 37% compared to the ones without press-fitting, and the most damage happened at the same node as the maximum von Mises stress. [ABSTRACT FROM AUTHOR]

The current research is concerned with unsteady boundary lamina flow in a porous material adjacent to a stretching-sheet, as well as a related heat transfer problem. The controlling PDEs and ODEs boundary layer for flow and for temperature by distribution were reduced using the similarity transformation method. These equations are solved numerically. MATLAB was used to conduct a numerical analysis of the influence of several Key parameters on rate distribution, distribution of temperature, pore, and friction of the skin, and rate of heat transformation on the Stretch sheet. [ABSTRACT FROM AUTHOR]

This research work successfully addresses the key issues related to the selection of optimal initial approximations depending on numerical parameters and available data in the context of reaction-diffusion. This approach significantly improves the accuracy and efficiency of monitoring and analyzing the dynamics of the reaction-diffusion process. In this study, it was shown that for the successful analysis and solution of complex nonlinear problems, it is effective to use the nonlinear splitting method and the method of standard equations. These methods have proven to be reliable tools for studying nonlinear phenomena in various systems. As a result of this study, a nonlinear splitting algorithm was justified, which is used to solve equations describing multicomponent cross-diffusion systems of a biological population. This algorithm provides an important tool for numerical simulation and analysis of such systems, providing more accurate and efficient results. The study confirms the significance of nonlinear splitting and reference equation methods in the context of nonlinear problems, and also provides a practical solution in the form of an algorithm for studying multicomponent cross-diffusion systems in biological populations. These results have potential for application in various fields of science and engineering, where modeling and numerical work with nonlinear differential equations is important. In addition, software packages have been created to help automate the processes of visualizing the development of solutions in time and space. These innovative tools provide the ability to conveniently observe and analyze the evolution of processes in various fields of science and engineering where complex dynamic systems, such as biological populations and others, are important. This work advances the understanding and modeling of complex reaction-diffusion processes and has potential applications in various disciplines of science and technology. [ABSTRACT FROM AUTHOR]

In this work, the initial and boundary problem is consider for the the process of heat propagation in a body consisting of two plates with different thermo-physical characteristics. Finite difference method used to solve the problem. Two regularizing procedures were used to obtain stable solutions. It is shown that with increasing distance between the point of measurement of the "initial data" and the boundary of the region, disturbance of the initial data, the stability of the solution deteriorates. [ABSTRACT FROM AUTHOR]

Variation in discharge and water levels in rivers due to climate change effects such as temperature differentials and increased precipitation in the upstream and downstream areas of river-based structures might lead to impacts on the safety of such structures. Al-Hindiya barrage is currently one of the most important engineering projects in Iraq, and one of the concerns of engineers during the operation of dams such as this, is the potential for leakage under the hydraulic structures, which may result from poor geological conditions and changes in water levels: if the leakage rate increases under the origin, this will affect the safety of the structure. This project utilised measuring devices (Piezometers) to monitor the water pressure in the foundations of the barrage to verify its safety. The variation of the water levels of the Al-Hindiya barrage was thus assessed in terms of its impacts on the seepage ratio, with numerical analysis in Geo-Studio SEEP/W used to determine the amount of leakage occurring in the structure, based on comparing the readings derived from the program with field readings to ensure precise evaluation of the model. All data entered into the Geo-studio program were thus provided by the Al-Hindiya Dam Irrigation Project Department. The amount of leakage occurring under the structure was found to be permissible, and the safety of the structure was thus confirmed. This was attributed to the quality of the cut-off wall and its efficiency in dissipating leakage under the structure, which increased the safety factor against uplift pressure and seepage pressure. The analysis demonstrated that the cut-off wall works effectively to reduce the hydraulic gradient in the horizontal and vertical directions, which helps by increasing the factor of safety against uplift pressure to about 5, protecting the barrage's body. This ensures that the barrage is safe, the concrete structures are of high quality, and that no form of concrete damage should arise even after a long period of operation. The analysis further highlighted that the maximum design level (flood conditions) had a reduced factor of safety of 3, however, leading to a recommendation that the water level not be permitted to reach this extent in order to protect the barrage from harm. [ABSTRACT FROM AUTHOR]

A heat sink is a device that removes heat from electronic devices that consume electricity. This heat removal is required to meet the equipment's design requirements. In this paper, different heat sink geometries are designed and simulated using computational fluids dynamic software to compare the temperature distribution and thermal performance. The main objective is to investigate the effect of the fin arrangement, base plate thickness and type of heat sink material on the thermal performance of heat sinks using the Ansys FLUENT 2021. The heat sinks have been analyzed at different heat load supply of 60 W, 70 W and 80 W. Three different fins arrangement of rectangular plates, rectangular pins and separated short plates heat sink are compared of the thermal performance in this study. The effects of heat sink materials on thermal performance were also investigated numerically. In this research work, thermal resistance is the parameter that determines the thermal performance of the heat sinks. The findings revealed that the thermal resistance is lower for the copper rectangular plates heat sink with 5 mm base plate thickness. [ABSTRACT FROM AUTHOR]

Replacement of soft clay soil technique is commonly utilized in the construction practices and engineers had proven that it may be one of the effective techniques. In addition, a number of researchers have already thought about the mechanisms of soil removal and replacement. The present research investigates efficiency of remove and replace approaches for the mitigations of the soft clays in the fact that analyses have been based upon the basic principles of stress-deformation. The main objective of the present work is to investigate the effectiveness of the replacement method. The finite element software PLAXIS was implemented in the present study in order to analyze the behavior of shallow footing. The present investigation considers the variation in replacement thickness, replacement width and the relative density of sand used in replacement. A total of 33 models represent two groups were performed. The first group consists of 16 models by using medium sand for soil replacement; the second group consists of 16 models by using dense sand for replacement of the soil both of 2 groups have been performed with various depth and width values of the replacement, besides one untreated soil model. Soil's bearing capacity that has been enhanced by the soil replacement was measured. It has been noticed that the capability of the replacement of the soft soil by the sandy soil for improvement of footing bearing capacity on the soil had shown a maximal improvement degree that has been accomplished in the case where soil has been treated through partially replacing it with the dimensions B soil replacement (B represents footing width) with an extension of (b=1.50-2.0) all the sides to a (1-2) B depth. The approach of the soil has a higher effectiveness in the improvement of bearing capacity when increasing replacement width in comparison to an increase of replacement depth. It has been found that bearing capacity of the footing is highly increased by increasing relative density of sand by compacting. [ABSTRACT FROM AUTHOR]

This study is concerned with the behavior of two convergent foundations resting on clay using three-dimensional plane strain finite element analysis. A Mohr-coulomb soil model was used to simulate soils using PLAXIS 3D V21, a finite element analysis software that perfectly simulates linear and plastic elastic behavior. The soil zone is divided into 10-node triangular points approach for calculating the mesh generation, with locally refined mesh near the foundations and very fine mesh near the domain boundaries. Differences in spacing between two foundations and new foundation depth are used to investigate their effects on settlement and tilt, the effect use skirted foundation as a new foundation. It was observed through numerical analysis that the interference affects the functions of the existing foundation and that the settlement and tilt decrease as the spacing between the two foundations increases. Also, increasing the depth of the new foundation leads to a decrease in the settling of the foundation and tilt. Also using a skirted foundation as a new foundation contributed in decrease risks of additional settlement and risk of tilt of existing foundation. [ABSTRACT FROM AUTHOR]