Effects Of Different Loading Conditions Research Articles

Energy absorption characteristics of hybrid hierarchical chiral structures based on symmetrical design under in-plane impact

Drawing inspiration from hierarchical structures, axisymmetric design layouts were introduced, and hybrid hierarchical chiral structures (HHCS) based on four- and six-chiral structures were proposed. The performance of HHCSs under in-plane compression is investigated using finite element methods and experiments. The effect of different loading conditions on the behavior of HHCSs is discussed. Under low-speed impact, HHCSs exhibit a negative Poisson’s ratio (NPR) effect, which diminishes as the velocity increases and the inertial effects gradually become dominant. The parameter study shows that increasing the connectivity between subunits and the thickness can enhance the energy absorption capacity of the structure while maintaining a good NPR effect. The conventional inclined deformation mode of the chiral structure is improved by the axisymmetric layout, which effectively improves the energy absorption.

Tribological Behavior of Direct Metal Laser Sintering–Manufactured Ti6Al4V Alloy in Different Biofluids for Orthopedic Implants

Abstract Ti6Al4V alloy is widely used in several engineering applications, especially in the biomedical field, because of its excellent biocompatibility, mechanical strength, and corrosion resistance. However, the Ti6Al4V alloy possesses poor tribological properties, which may lead to premature failure of the implants. From the available literature, it has been found that the wear properties of direct metal laser sintering (DMLS)-produced Ti6Al4V alloy in different lubrications have not been explored in detail. The present study tries to evaluate the tribological behavior of DMLS-manufactured Ti6Al4V alloy in different biofluid conditions, such as physiologic saline solution, simulated body fluid, and phosphate-buffered saline against an Al2O3 ball. Apart from the fluids, the effect of different load conditions like 5 N, 10 N, and 20 N at 0.157 m/s (500 rpm @ 6 mm track dia.) was also evaluated on the ball-on-disk tribometer. The experimental results have shown that the DMLS-produced Ti6AL4V alloy yields a 23% lower coefficient of friction and a 68% lower wear rate as compared to the cast Ti6Al4V. Additionally, cast and DMLS-produced Ti6Al4V alloys have followed the same wear trend for biofluids phosphate-buffered saline > simulated body fluid > physiologic saline solution. Analysis of variance (on the obtained results), field emission scanning electron microscopy, and electron dispersive spectroscopy were performed to investigate the reason behind the obtained wear behavior. The results have confirmed that the lesser wear of DMLS-produced Ti6Al4V is mainly due to its hydrophilic nature and higher hardness. Additionally, adhesion, abrasion, and oxidation were found to be the dominant wear mechanisms in both types of samples.

FEM Simulations of Fatigue Crack Initiation in the Oligocrystalline Microstructure of Stents.

For over two decades, vascular stents have been widely used to treat clogged vessels, serving as a scaffold to enlarge the narrowed lumen and recover the arterial flow area. High-purity oligocrystalline austenitic steel is usually applied for the production of stents. Despite the popularity and benefit of stenting, it still may cause serious clinical adverse issues, such as in-stent restenosis and stent fracture. Therefore, the study of the mechanical properties of stents and in particular the prediction of their life cycles are in the focus of materials research. In our contribution, within the finite element method, a two-scale model of crack initiation in the microstructure of stents is elaborated. The approach is developed on the basis of the physically based Tanaka-Mura model (TMM), considering the evolution of shear bands during the crack initiation phase. The model allows for the analysis of the microstructure with respect to the life cycles of real materials. The effects of different loading conditions, grain orientation, and thickness of the specimen on Wöhler curves were analysed. It was found that the microstructural features of oligocrystals are very sensitive to different loading conditions with respect to their fatigue behaviour and play a major role in fatigue crack initiation. Different grain-orientation distributions result in qualitative and quantitative differences in stress distribution and in the number of cycles for crack initiation. It was found that presence of a neutral zone in the cut-out of the microstructure under three-point-bending loading conditions changes the qualitative and quantitative patterns of stress distribution and affects the number of cycles for crack initiation. It was found that under both tensile and bending loading conditions, thicker specimens require more cycles for crack initiation. The Wöhler curves for crack initiation in oligocrystalline microstructures of stents could be compared with the ones in the experiment, taking into account that for high cyclic fatigue (HCF), typically, more than 70% of the cycles refer to crack initiation. The developed numerical tools could be used for the material design of stents.

A mechanical properties and failure mechanism study for resistance spot welded AHSSs under coach-peel and lap-shear loads

Based on mechanical tests, microstructure characterizations and finite element simulations, the mechanical properties and failure mechanisms of resistance spot welds (RSWs) were investigated in the study. Different types (B1500HS, 340/590DP, 420/780DP and 820/1180DP) and thicknesses (1.2–1.8 mm) of steel plates were welded as coach-peel (CP) samples. To quantify the effect of plate thicknesses on the failure bending moment, MCP, of CP samples, a new parameter, standardized failure bending moment, MSCP = MCP /T1 /T2, was introduced. Based on the new revealed relationship between the MSCP and low strength metal plate tensile strengths (LSMP σb), a MCP prediction model was provided. Moreover, the lap-shear (LS) test data (standardized shear strength, σSS) published in a previous work were also analyzed. With the increment of σb values (<800 MPa), σSS and MSCP parameters increased linearly. When the σb values > 800 MPa, the slopes of σSS and MSCP fitting lines were decreased. The similar variation trends of σSS and MSCP parameters implied similar RSW failure mechanisms. The new revealed relationship between the RSW minimum hardness values (Hmin, measured from base metals or heat affected zones) and LSMP σb values can explain the trends. Finally, by simulations analyses, the effect of different loading conditions on the mechanical performance of RSWs was also studied. CP loads induced the most severe stress concentration near the RSWs, which can severely weaken RSW mechanical performance.

Effect of different loading conditions on corrosion fatigue crack growth rate of a nickel-based alloy in supercritical water

Advanced ultra-supercritical (A-USC) technology improves the initial steam temperature to 650 °C and more. In such an extremely corrosive medium environment, metallic materials are susceptible to corrosion fatigue. In the present study, the aim is to evaluate the effect of maximum stress intensity factor (Kmax), stress ratio (R), waveform, frequency, and holding time (th) on the corrosion fatigue cracking behavior of C-HRA-2 (a candidate nickel-based alloy for A-USC units) in supercritical water (650 °C/25 MPa). The results show that with the increase of Kmax, the corrosion fatigue crack growth rate (CFCGR) increases and satisfies the exponential relationship. The decrease in R and frequency both cause the rise of CFCGR, which satisfies the logarithmic linear relationship. Sinusoidal and triangular wave loading have no significant effect on the CFCGR. Trapezoidal wave with th has a larger CFCGR while with the rise in th, the CFCGR increases. The crack propagation path is straight, perpendicular to the loading direction, and secondary cracks are also observed. Transgranular and intergranular mixed fractures occurred during continuous loading. The proportion of intergranular fracture increases significantly as holding time is applied. The corrosion fatigue crack growth of C-HRA-2 in supercritical water can be explained by dynamic embrittlement mechanism.

Cohesive Zone Model to Investigate Complex Soft Adhesive Failure: State-of-the-Art Review

Soft adhesives are widely used in soft robotics, biomedicine, flexible electronics and other fields. In practical applications, soft adhesives are frequently subjected to monotonic loading, static loading and cyclic loading. It is extremely important but challenging to analyze the failure behavior of soft adhesives due to their complicated mechanical properties and failure mechanisms, as well as the effect of different loading conditions. In this paper, the methodology of developing the cohesive zone model (CZM) for understanding the failure behavior of soft adhesives is systematically reviewed. First, for the one-time failure of soft adhesives, the establishment of the CZM considering the effect of loading rate, fibrillation, and mixed-mode loading is summarized. Second, the delayed failure of soft adhesives is studied. The development of the corresponding CZM considering the creep behavior under constant force and various potential mechanisms to explain the delayed failure under displacement holding is discussed. Then, for the fatigue failure of soft adhesives, remarks for CZM that are capable of expressing the loading-unloading process under the high cycle fatigue process and addressing the effect of viscoelasticity on fatigue damage have been provided. Finally, based on the application of soft adhesives in the frontier areas, the challenges and prospects faced for future research are presented.

Identifying the mechanism of the fatigue behavior of the composite shaft subjected to variable load

This paper presents a finite element analysis of a composite shaft under dynamic variable fatigue loading. The object of this study is the behavior of the fatigue life of a composite shaft under dynamic variable fatigue loading. The fatigue life of the shaft is then determined by analyzing the stress distribution and its effect on the material's fatigue strength. The investigation of fatigue behavior involves evaluating factors such as stress concentrations, fatigue crack initiation and propagation, and the cumulative damage caused by cyclic loading. The study explores the impact of biaxial loading on the shaft's fatigue performance and provides insights into its significance in predicting fatigue life and it is 10e7 cycles. Furthermore, a damage indicator is predicted to assess the accumulated damage and monitor the progression of fatigue-related degradation. This indicator serves as a valuable tool for predicting the remaining useful life of the composite shaft. The equivalent alternative stress is calculated to characterize the combined effect of different loading conditions on the fatigue life of the composite shaft. By quantifying the stress level and variations experienced by the structure, this parameter allows for a comprehensive assessment of the fatigue performance under variable loading scenarios 250 N. The findings of this research contribute to the understanding of fatigue behavior in composite shafts under dynamic variable fatigue loading. The insights gained from the fatigue life investigation, biaxiality indication, damage prediction, and equivalent alternative stress calculation can aid in optimizing design considerations, maintenance planning, and enhancing the reliability and durability of composite shafts in various engineering applications

Topology Optimisation of Piston

Abstract: This research paper presents a comprehensive study on the topology optimization of a piston component manufactured through 3D printing technology. The study employs a combination of SolidWorks and ANSYS software to model and simulate the piston's structural behavior under different loading conditions. The optimized piston design is produced using PLA material through Ultimaker Cura software. The topology optimization process involves defining the design constraints and objectives, which are optimized to produce an optimal design with reduced weight while maintaining the required structural integrity. The paper investigates the effects of different loading conditions on the piston's structural performance and shows how the optimized design can enhance the piston's mechanical properties. The results show that the topology optimization process results in a piston design that reduces weight while maintaining the required strength and performance, thereby enhancing the efficiency of the 3D printing process. The study contributes to the growing body of research on the use of topology optimization in additive manufacturing and provides insights into the practical implementation of this approach in piston design.

Numerical simulation of long-term performance of deep geological repository placement rooms in crystalline and sedimentary rocks

Evaluation of the stability of placement rooms and damages in the geosphere surrounding a deep geological repository (DGR) for high-level nuclear waste are essential components for assessing the overall repository performance. Assessments of the performance of placement rooms for the duration of the regulatory period (typically 1 million years) usually involves simulations using numerical codes capable of modeling coupled thermo-hydro-mechanical (THM) processes induced by different natural and repository-induced perturbations over different time and length scales. The numerical constitutive model used to represent the host medium should be capable of capturing highly nonlinear responses to stress changes, including development of damage and fracturing. In this study, a novel approach for simulation of damage evolution and fracturing around the repository rooms, based on the bonded block model (BBM) devised for analyzing coupled THM processes, is used to perform a study of the long-term geomechanical performance of the Nuclear Waste Management Organization hypothetical DGR configurations in sedimentary and crystalline geological settings. The perturbation effects of different loading conditions, including in-situ stress changes by room excavation, heat generated from the used fuel canisters, and glaciation were analyzed. Each THM analysis was conducted using a 3D continuum numerical code to generate evolving temperature and pore pressure fields in the rock mass. The temperature and pore pressure data were then imported in the 2D BBM model for simulating evolution of damage around the placement rooms. Sensitivity analysis was conducted to investigate the effect of different poro-mechanical parameters, rock mass permeabilities, and different approaches for calibrating the BBM, on predictions of room stability and extent of the excavation damage zone around the placement room. The modeling results indicate that the confinement provided by the bentonite backfill inside the room clearly prevents any unravelling but also limits the extent of the damage to less than 1.6 m into the room walls in any of the analyzed cases considering different loading conditions and uncertainty of the material properties.

Fatigue-life and stress distribution of a glass-ceramic under different loading conditions

This study aimed to evaluate the effect of different loading conditions on the mechanical behavior and stress distribution of a leucite-reinforced glass-ceramic. Plate-shaped ceramic specimens were obtained from leucite-reinforced glass-ceramic (1.5 × 8.4 × 8.3 mm) and adhesively cemented to a dentin analog substrate. Monotonic and cyclic contact fatigue tests were performed to simulate sphere-to-flat contact, using a 6 mm diameter spherical piston; and flat-to-flat contact, using a 3 mm diameter flat piston. For the monotonic test (n=20), a gradual compressive load (0.5 mm/min) was applied to the specimen using a universal testing machine. Failure load data were analyzed with Weibull statistics. The cyclic contact fatigue test was performed using protocols (load and a number of cycles) defined by the boundary technique (n=30). Fatigue data were analyzed using an inverse power law relationship and Weibull-lifetime distribution. The stress distribution was investigated using Finite Element Analysis (FEA). The monotonic and the fatigue Weibull modulus were similar among the two contact conditions. In fatigue, the slow crack growth exponent was greater for sphere-to-flat contact, which indicates that the load level had a greater effect on the specimen's probability of failure. In conclusion, FEA showed different stress distribution for the tested loading conditions. The stress distribution and probability of fatigue failure of specimens tested in sphere-to-flat contact showed greater dependency to load level.

Thermally induced fracture analysis of CNT reinforced FG structures with multiple discontinuities using XIGA

In this paper, the authors have employed XIGA to perform the fracture analysis of carbon nanotubes (CNT) reinforced functionally graded (FG) structures with discontinuities subjected to a coupled loading condition (thermo-mechanical load). For the first time, XIGA is used to analyse cracked CNT reinforced FG structures. The exponential rule is supposed to regulate the material property gradation in FG (which is made up of metal (Ti–6Al–4V) and ceramic (ZrO2)) structures. Several micromechanics models are utilized for evaluating the equivalent mechanical and thermal properties of CNTs (SWCNT and MWCNT) reinforced FG structure. To capture the discontinuity along the singular fields near the crack tip and the crack face, appropriate enrichment functions are used. Investigations are performed to estimate the effects of inclusions and holes on the SIFs of FG structures reinforced with CNT. Also, the effect of mechanical properties (Young’s modulus) of inclusion and percentage content of CNTs (SWCNT & MWCNT) on SIFs is explored. Furthermore, the authors have investigated the effect of different loading conditions on the SIFs.

The effect of Lode parameter on the yield surface of Schoen's IWP triply periodic minimal surface lattice

Owing to the advancements in additive manufacturing and increased applications of additively manufactured structures, it is essential to fully understand both the elastic and plastic behavior of cellular materials, which include the mathematically-driven sheet lattices based on triply periodic minimal surface (TPMS) that have received significant attention recently. The compressive elastic and plastic behaviors have been well established for many TPMS latticed structures, but not under multiaxial loading. Furthermore, TPMS lattices are computationally expensive to model explicitly when used in latticing various structures for enhanced multi-functionality, and hence the need to develop accurate yield surfaces in order to capture their plastic behavior in a homogenized approach. The majority of previous yield surfaces developed for cellular materials originate from cellular foams, and limited attempts has been made to develop yield surfaces for TPMS lattices. In this study, a numerical modeling framework is proposed for developing the initial yield surface for cellular materials and is used to develop the initial yield surface for Schoen's IWP sheet-based TPMS cellular lattices. The effect of different loading conditions on the effective yield strength of the IWP sheet-based (IWP-s) TPMS lattice is numerically investigated, based on a single unit cell of IWP-s under fully periodic boundary conditions, assuming an elastic-perfectly plastic behavior of the base material, for relative densities (ρ‾) ranging from 7% to 28%. In order to account for different loading conditions, the stress state is characterized in a generalized fashion through the Lode parameter (L). The effect of L is studied over a range of mean stress values (σm) to understand the effect of both L and σm on the effective yield strength. An initial yield surface is developed incorporating the effect of L, σm and ρ‾, and is validated numerically showing rather good agreement. In the 3D principal stress space, the shape of the yield surface for the IWP-s lattice resembles the shape of a cocoa pod.

New formulas for predicting the lateral–torsional buckling strength of steel I-beams with sinusoidal web openings

Lateral torsional buckling (LTB) of steel I-beams is characterized by simultaneous lateral deflection and twist. LTB is an instability failure mode that has been intensively investigated. However, existing standard procedures and formulations still have limitations in determining the LTB ultimate moment, especially when considering the use of perforated beams. Consequently, in the current paper, by conducting an extensive parametric study, it was tried to investigate the effect of all main parameters as well as the effect of different loading conditions on the ultimate LTB resistance of steel I-beams with sinusoidal web openings. Then, based on the provided database, the artificial neural network (ANN) method was employed, and based on it, a high-precision formulation was proposed to predict the ultimate LTB strength of steel I-beams. In addition to the ANN method, a regression-based formula was also developed as a classical method to examine the differences between the two methods. Finally, the proposed formulas were compared with other existing formulas for estimating the LTB strength. The results showed that the proposed formula based on ANN not only present a reasonable accuracy compared to the existing formulations but also can be used by engineers as practical equations in the design of I-beams with sinusoidal web openings.

Dynamic Response Analysis of Offshore Converter Station Based on Vector Form Intrinsic Finite Element (VFIFE) Method

This study aims at proposing a simulation method for an offshore converter station platform (OCS) under dynamic loading. A user-defined in-house FORTRAN code was developed based on the Vector Form Intrinsic Finite Element (VFIFE) method, and the numerical model was validated by test data. After model validation, the dynamic behavior of the OCS was carefully studied and the effect of different loading conditions, including seismic, hydrodynamic and wind load, on the dynamic behavior of OCS was investigated. The time history of the structural response was obtained, and the relationship between the structural peak response and the peak value of the seismic load was also shown. It indicated that water damping accelerates energy consumption, while the effect of hydrodynamic and wind load has little influence on the cases studied in this work. Generally, the peak response increases almost linearly with the increase in the peak acceleration of the ground, and the seismic propagating direction has a great impact. In addition, both a whipping effect and stretching-squeezing effect were observed, and the vertical acceleration response of the valve hall deck is much higher than other structures, which is caused by the relatively lower local rigidity of the large-span structure and the inertia force caused by the valve tower.

Effect of Different Loading Conditions on the Fatigue Response and Recovery of Neat and Modified Asphalt Binders

Abstract Thixotropic behavior is a reversible process that occurs in asphalt binders because of the breakage and restoration of the binder’s microstructure. Thixotropic effects are associated with load applications and are fully recoverable when the loading is discontinued. Fatigue loading results in a decrease in the asphalt binder’s modulus related to reversible phenomena such as thixotropy, healing, and self-heating, in addition to irreversible permanent fatigue damage. The study of thixotropy is important to better characterize damage because of fatigue. In this study, four different asphalt binders were tested to determine their thixotropic behavior, namely two neat PG64-16 binders from different refineries, a polymer modified PG64-28 binder, and a tire rubber modified PG64-28 binder. The binders were short-term aged using a rolling thin film oven and tested with a dynamic shear rheometer at temperatures that produced an initial modulus of 35 MPa at sinusoidal strain amplitudes of 1.2 and 1.4 %, and an initial modulus of 50 MPa at strain amplitudes of 1 and 1.2 %. The test temperatures corresponding to the initial moduli for each binder were determined using a temperature sweep at a test frequency of 10 Hz. The test temperature and strain amplitudes were applied for 500 or 1,000 s followed by rest periods to determine the effects of loading time on the rates of binder modulus recovery for the different conditions. The results indicated that the thixotropic recovery rate is dependent on the binder type, with the tire rubber modified binder showing the fastest recovery rate and the polymer modified binder showing the slowest recovery rate. The recovery rate was also shown to increase with increasing initial modulus and strain amplitude.

A New Formula for Predicting Lateral Distortional Buckling Strength of I-Beams Subjected to Different Loading Conditions

Lateral distortional buckling (LDB) mode has been investigated as one of the failure modes in steel I-beams. The LDB mode in such beams is known by simultaneous lateral deflection, twist, and cross-sectional change due to web distortion. However, many studies have been conducted to investigate the behavior of this failure mode; so far, no formula has been found to calculate the ultimate LDB resistance of I-beams, which also takes into account the effect of different loading conditions. Consequently, in the current paper, by conducting an extensive parametric study, it was tried to investigate the effect of all main parameters as well as the effect of different loading conditions on the ultimate LDB resistance of I-shaped beams. Then, based on the provided database, the artificial neural network (ANN) method was employed, and based on it, a high-precision formulation was proposed to predict the ultimate LDB strength of steel I-beams. In addition to the ANN method, a regression-based formula was also developed as a classical method to examine the differences between the two methods. Finally, the proposed formulas were compared with other existing formulas for estimating the LDB strength. The results showed that the proposed formula based on ANN not only presents a reasonable accuracy compared to the existing formulations but also can be used by engineers as practical equations in the design of I-beams.

Experimental testing of full-scale fiber reinforced elastomeric isolators (FREIs) in unbounded configuration

Fiber reinforced elastomeric isolators (FREIs) have shown to be a promising option as an alternative to classical steel reinforced elastomeric isolators (SREIs). Previous investigations were limited to scaled-geometries without any attempt to test such devices under code-compliant protocols as per international standards. In the present study the authors investigated two circular full-scale (diameter 620 mm) FREIs manufactured with a non-standard process adopting a soft rubber compound and polyester fibers. Experimental tests were performed in unbounded configuration through the large anti-seismic device test facility at the EUROLAB of the University of Messina, Italy. A significant number of protocols were imposed to the prototypes in order to demonstrate the effect of different loading conditions, i.e., strain level, frequency of the excitation, axial load and repeated loading. The tests confirmed the significant dependency of mechanical behavior on axial load which tends to increase damping (i.e., higher friction mechanisms) while reducing stiffness (i.e., lower stability limits). Due to internal slippage at the fiber-rubber layers interface, damping capacity of FREIs achieved 20% of critical, i.e., significantly higher than that commonly achieved in SREIs with the same rubber compound. Even if adequate capacity was reached in compression, the run-in effect would limit the axial stiffness of FREIs. A significant roll-over phenomenon was detected under lateral loading up to a maximum shear strain of 100% without damage and permanent deformation after unloading. A numerical study finally demonstrated the effectiveness of FREIs when compared to SREIs in a base isolation system designed for a 3-storey reinforced concrete frame located in a high seismicity region in Italy. Lower axial stiffness of FREIs did not affect the seismic performance of the building due to limited rocking motion component and beneficial higher damping mechanism. This paper provides a significant contribution to the standardization of FREIs to be adopted in base isolation of conventional buildings.

Effects of different loading conditions on BS460B steel reinforcing bar using Multiphysics modelling technique

Nowadays, BS460B bar (steel reinforcing bar) also called as rebar are very useful to strengthen the concrete constructions and gives support to the constructions. In this study five samples of BS460B bars are developed using different loading conditions. This present article shows the simulation performed to investigate the effects of the different loads and corresponding von Mises stresses developed when the load is applied. This modelling and simulation for the BS460B bars using Structural Mechanics Module were performed in the COMSOL Multiphysics 5.5. This present article also investigated the total deflection under gone by the bars under different loading conditions. The effects of different loading conditions were evaluated in terms of the von Mises stresses (principal stresses), and the total displacement developed in the rebar steel. From the obtained results it is observed that on increasing applied load, von Mises stresses increases linearly with the load applied which is presented in the graph.

Behavior of CFRP-confined Concrete-filled square steel tube columns with section circularized under axial compression

Eight carbon fiber-reinforced polymer (CFRP)-confined concrete-filled square steel tube (CFSST) specimens and twelve CFRP-confined CFSST specimens with section circularized were tested under axial compression to investigate the effect of different loading conditions and CFRP layers on axial compressive behavior of CFRP-confined CFSST columns with section circularized. Experimental results indicated that section modification method (circularization) improves the CFRP confinement and increases bearing capacity of CFSST columns. Meanwhile, the effect of CFRP layers on the bearing capacity of CFSST columns is also evident. Combination models of Han–Lam & Teng and Mander–Pham & Hadi are suggested in this study for calculating the bearing capacity under different loading conditions. Results showed that predictions are consistent with the experimental results.

Optimization-based subject-specific planar human vertical jumping prediction: Model development and validation.

Jumping biomechanics may differ between individuals participating in various sports. Jumping motion can be divided into different phases for research purposes when seeking to understand performance, injury risk, or both. Experimental-based methods are used to study different jumping situations for their capabilities of testing other conditions intended to improve performance or further prevent injuries. External loading training is commonly used to simulate jumping performance improvement. This paper presents the optimization-based subject-specific planar human vertical jumping to develop the prediction model with and without a weighted vest and validate it through experiments. The skeletal model replicates the human motion for jumping (weighting, unweighting, breaking, propulsion) in the sagittal plane considering four different loading conditions (0% and 10% body mass): unloaded, split-loaded, front-loaded, and back-loaded. The multi-objective optimization problem is solved using MATLAB® with 35 design variables and 197 nonlinear constraints. Results show that the model is computationally efficient, and the predicted jumping motion matches the experimental data trend. The simulation model can predict vertical jumping motion and can test the effect of different loading conditions with weighted vests and arm-swing strategy on the ground reaction forces. This work is novel in the sense that it can predict ground reaction forces, joints angles, and center of mass position without any experimental data.