Three-dimensional Dynamic Analysis Research Articles

Exploring Stresses in Mandibular Jawbone during Implant Insertion: A Three-Dimensional Explicit Dynamic Analysis

In dental implant insertion, an artificial foundation is prepared for the prosthetic device, which involves the surgical positioning of the implant in the jaw bone. The success of dental implants relies on the osseointegration process. The biomechanical factors, such as stress and strain, developed during the insertion affect the jawbone and its surroundings. In this current study, the stresses during the implant insertion in the mandibular jawbone bone are analyzed using three-dimensional explicit dynamic analysis, and the Cowper–Symonds model is implemented with the damage model. The implant’s design has a substantial impact on stress distribution within the cancellous bone during the insertion procedure. The stress variation takes place as the implant moves into the pre-drilled hole. This is because of the contact between the bone and the fixture on the implant. The upper edge of the predrilled site shows that the stresses are more at the crestal region of the implant due to surface area. There is a gradual increase in the stress level as the implant reaches the lower edge from the top edge. This is because of the concept of mechanical interlocking. Clinicians can use this information to anticipate and address potential stress-related challenges during implant placement.

Three-Dimensional Dynamic Modelling and Analysis of a Dual-Cable Winding Hoisting System

In this paper, a three-dimensional dynamic model of a dual-cable winding hoisting system is presented to simulate and analyze its coupled vibrations. The equations of motion of this system are derived based on a substructure method and Lagrange’s equations of the first kind, in which the longitudinal–torsional coupled mechanical characteristics of the hoisting cables are considered. Longitudinal and transverse natural frequencies of the system are obtained and studied, and its dynamic responses due to some assumed displacement excitations are calculated. Numerical results agree well with those from ADAMS simulation, and the results have shown that longitudinal and transverse resonances are inevitable, but the transverse resonance has little effect on the conveyance; Slow longitudinal excitations should be avoided, thus avoiding the first-order longitudinal resonance since the system longitudinal vibration is dominated by its first-order mode; the torque in the hoisting cable is mainly induced by its tension under longitudinal–torsional coupled mechanical characteristics of the cable, and a torque release device is suggested to protect the hoisting cable from torsion failure; Torsional and transverse vibrations of the conveyance are been well restricted by the guiding cables even when the guiding cable pre-tension is zero. The results of this paper can be used to improve the parameter design of the ultra-deep shaft hoisting systems.

Comparative Studies between Frequency Domain Analysis and Time Domain Analysis on Free-Field One-Dimensional Shear Wave Propagation

In Korea, the underground silo structure for low- and intermediate-level radioactive waste disposal facilities has been constructed and operated since 2014. Large-scale earthquakes occurred in 2016 and 2017, respectively, in Gyeongju and Pohang areas near the underground silo structures, and interest in the stability of the underground silo increased significantly. In this paper, one-dimensional free-field analyses have been carried out before the three-dimensional silo dynamic analyses subjected to earthquake loadings. As an additional study, a new form of the finite element equilibrium equation is derived in terms of relative motions, which is essentially the same equation expressed in terms of total motions where the base shear force is applied to the earthquake load. The accuracy of conventional finite element solutions is evaluated by directly comparing them with closed-form solutions by frequency domain analysis such as SHAKE91.

Design of precision seeding device based on hexarotor UAV platform and its application in hard soil

Drones, also known as unmanned aerial vehicles (hereinafter referred to as UAV), are widely used in both military and civilian applications, but agricultural drones have made great strides in recent years. Agricultural drones are often used to detect and evaluate crops, aid crop pollination, and spray fertilizers and disperse seeds. However, in terms of seed seeding, the vast majority of drones can only achieve extensive sowing of seeds, and seeds can only be sown on the surface of the soil, and the sowing accuracy of this method is extremely low, and there is a large waste of seeds. In order to improve the sowing efficiency of UAVs and the sowing effect on hard soil, this paper conducts relevant research on the seeding device carried by UAV and designs a new seeding device. On the basis of the traditional spreading function, the device performs design calculation, three-dimensional dynamic feasibility analysis, and is equipped with a precise interval sowing mechanism, which can also send seeds into the deep soil while accurately sowing seeds, which solves the problem of low efficiency of UAV seeding.

Three-Dimensional Static and Dynamic Analyses of an Embedded Concrete-Face Rockfill Dam

Concrete-face rockfill dams have gradually become the preferred dam type in the engineering community. This study presents a hydropower station in China as a case study to introduce a new type of embedded concrete-face rockfill dam. The static and dynamic stress–strain characteristics of the proposed and conventional concrete-face rockfill dams were compared, and the optimal height of the embedded concrete body at the hydropower station was determined. The results indicate that, under static conditions, the embedded concrete body could reduce deformation upstream and downstream of the rockfill body, eliminate tensile stress along the concrete-face slab slope, reduce concrete-face slab deflection, and increase the maximum deflection area to 0.47 times the dam height. The inhibitory effect of the embedded concrete body on the stress and strain of the dam body became more evident as the size of the embedded body increased. Although the embedded concrete body did not enhance the dynamic and superposed static–dynamic stress states of the embedded concrete body and rockfill, the stress and strain increase in the dynamic state were within a controllable range. Through a sensitivity analysis and considering the terrain conditions and engineering cost of the hydropower station, the height of the embedded concrete body is recommended to be 0.4 times the dam height.

The role of bone morphology of the greater tuberosity and lateral acromion on subacromial space during scaption: a three-dimensional dynamic simulation analysis

BackgroundThe bone morphology of the greater tuberosity and lateral acromion plays a central role in subacromial impingement syndrome. The critical shoulder angle (CSA) and greater tuberosity angle (GTA) are two-dimensional measurement parameters that have been validated to evaluate it radiologically. These markers are, however, static and don’t consider the dynamic effect of glenohumeral motion.ObjectivesThis study aimed to better understand the biomechanics in subacromial impingement with a dynamic simulation based on a validated 3D biomechanical model coupling joint kinematics and 3D reconstructed computed tomography.Study design & methodsSixty-one patients were included in this study: a case group of 44 patients with degenerative rotator cuff tears involving only the supraspinatus, and a control group of 17 without a rotator cuff tear. Patients with previous surgeries, traumatic cuff tears, and cuff tear arthropathy were excluded. CSA, GTA, and impingement-free range of motion (IF-ROM) of the glenohumeral joint in scaption were calculated. Correlation tests were used to determine the relationship between ROM and CSA, GTA, and combined CSA and GTA values.ResultsCSA and GTA were significantly higher in the rotator cuff tear group (p = 0.001 and < 0.001), while IF-ROM was significantly higher in the control group (p = 0.001). There was no overall correlation between CSA and GTA (R = 0.02, p = 0.8). Individual correlation between both angles with IF-ROM was negatively weak for CSA (R = -0.4, p < 0.001) and negatively moderate for GTA and IF-ROM (R = -0.5, p < 0.001). However, combining both angles resulted in a negatively high correlation with IF-ROM (R = -0.7, p < 0.001).ConclusionSubacromial space narrowing during scaption is highly correlated to the cumulative values of GTA and CSA. These findings suggest that the combined bony morphology of the lateral acromion and greater tuberosity plays an important role in subacromial impingement.Level of evidenceIII

Three-Dimensional Electromagnetic and Structural Analysis of Disruptions in the COMPASS Upgrade Vacuum Vessel

Structural analyses of disruptions and the electromagnetic (EM) analyses to support them typically use symmetry to produce a manageable model size. Nonaxisymmetric halo loads require larger analysis models. In this paper, the results of transient EM analyses of halo strikes during a vertical displacement event are presented. The plasma motions and halo characteristics are prescribed based on analyses performed by the Institute of Plasma Physics of the Czech Republic. The time transient EM solution provides loads to a full three-dimensional transient dynamic analysis of the vacuum vessel. The responses to large lateral halo loads are altered and mitigated by the mode responses of the vessel. Dynamic load factors are computed for specific locations in the vessel and supports.

Stabilized low-order finite-element formulation for static and dynamic simulation of saturated soils based on a hybrid integration scheme

This paper presents a stabilized linear finite-element formulation for three-dimensional (3D) elastoplastic static and dynamic coupled analyses of the soil skeleton and pore fluid. The proposed hybrid integration scheme can improve the speed and accuracy of the simulation while ensuring stability. The one-point reduced integration with hourglass stabilization and anti-locking strategy was used for the stress–strain calculation, while the full integration was adopted for analyzing other parts, such as the fluid phase. A robust pore-pressure stabilization method was derived to solve the oscillation problem for equal-order linear interpolation in the incompressible-undrained limit. In the field of large-scale 3D elastoplastic coupled solid–fluid simulations, academia has been committed to finding a method that considers the speed, stability, and accuracy of the simulation. The proposed finite-element formulation provides an effective solution for this purpose.

Seismic fragility of low-rise piloti buildings based on 2017 Pohang earthquake damage

Due to the 2017 Pohang earthquake, many low-rise piloti buildings suffered minor to severe damage. Low-rise piloti buildings in Korea are generally both vertically and horizontally irregular systems. The first floor is a weak and soft story, and the core wall is located at the corner or edge of the plan creating a horizontal irregularity. Furthermore, the damage investigation indicates that the insufficient amount of column hoops and poor detailing of reinforcement. It was presumed that the combination of soft story, torsional behavior and poor detailing brought brittle failure at the columns located at the furthest distance from the core. Such a brittle and irregular nature makes it difficult to predict damage with a HAZUS-type approach, which uses seismic fragility functions defined in terms of the spectral displacement and the capacity spectrum method based on pushover analyses. Comparison of pushover analysis results of piloti buildings indicated that location of peak and overall deformation capacity differed with the intensity of the torsional behavior and failure mode of the column. Therefore, this study aimed to develop an improved seismic fragility function for piloti buildings. To reflect the observed damage, the use of damage criteria based on member performance, including stress and strain, and spectral acceleration was proposed. Fragility functions for the piloti buildings were constructed by using three-dimensional incremental dynamic analyses. Damage estimates for piloti buildings in the target area that were obtained by using obtained fragility functions showed good correlations with damage survey data.

Numerical Simulation of a Barge Impact on Bridges with Different Configurations of Pile Group Foundations

Three-dimensional finite element dynamic analyses were conducted to evaluate the effect of barge impact of different speeds on the lateral performance of three pile group (PG) configurations (vertical, battered, mixed) in terms of peak lateral displacement, peak shear force, lateral stiffness of PGs, and contribution of piles and pier columns to the total resisting force. The concrete material was modeled using the Concrete Damaged Plasticity model. The clay behavior was described using the Modified Cam Clay model; while the sand was modeled using the Drucker Prager model. The results showed that the vertical PG had the lowest lateral stiffness; while the battered and mixed PGs had closely larger stiffness, which allowed the development of larger impact force and pile cap displacement in vertical PG as compared to other PGs. The results of shear force showed that the foundation contributed up to 82% of the total lateral force in battered and mixed PGs. The results also showed that in vertical PG, the first row had slightly higher percentage of lateral force compared to other rows; while in battered PG, the load percentage was evenly distributed between rows. A contrast performance was observed for mixed PG. The results of bending moment (BM) showed that the piles in vertical PG had notably higher BM than the piles in other PGs due to larger pile cap displacement. In all PGs, the piles in the edge column had higher BM ratio, with the leading row (L) had the highest BM ratio (69–72%) in all PGs.

Fragility and comfortability curves development and seismic risk assessment of a masonry building under earthquakes induced by geothermal power plants operation

This research is an attempt to estimate the seismic risk of geothermal power plants (GPPs) operation on the masonry buildings located in the vicinity of these infrastructures through a probabilistic framework. In this regard, a typical masonry building in Germany is considered. In the first part, the fragility and comfortability curves of this building are established. For this purpose, a set of 30 ground motions recorded due to GPPs activity are used for performing elaborated three-dimensional nonlinear incremental dynamic analysis to construct the fragility and comfortability curves. In the second part of the research work, by using the Monte-Carlo simulation technique and adopting the hazard model capable of simulating both seismological characteristics and ground motion intensities, the required number of probable hazard scenarios are generated for different ranges of GPPs injection flow rates. Afterward, the seismic risk imposed on the masonry building is evaluated by considering the developed fragility and comfortability curves. The outcomes highlight that the risk of facing structural damage is not significant; however, the disturbance of buildings’ residents is highly probable and can lead to considerable seismic risk. In addition, in the close vicinity of the earthquake epicenter (less than 5 km), the estimated risk increases tangibly in comparison with the larger distances (more than 15 km).

A fully nonlinear three-dimensional dynamic frictional contact analysis method under large deformation with the area regularization

A fully nonlinear three-dimensional dynamic frictional contact analysis method under large deformation with the area regularization

Spatially varying earthquake ground motion: artificial generation and effects on earth-fill dam behavior

ABSTRACT The observed amplitude and phase differences of seismic ground motions recorded at different locations over extended areas are termed as spatially varying earthquake ground motion (SVEGM). Earthquake-resistant design and seismic risk assessment of extended structures require three-dimensional dynamic analyses for which the excitation is needed in the form of three-directional SVEGM components, where each component needs to be consistent with the coherency model. In this paper, the principal features of the performed analyses are as follows: (1) discretisation of the spatial domain at the foundation base, (2) the selection of coherency model and (3) propagation angle of the seismic waves. In the first part of the paper, three cases for the generation of three-directional SVEGM are presented. First, the two-dimensional spatial domain, representing the foundation base of the extended structure, is discretised. Second, for case 1, the three-directional SVEGM is generated using the Liu and Hong coherency model at the cells of the grid. In this case, the loss of coherency is considered independent of the direction of the wave propagation (case general). Then, for the case 2, the two different propagation angles of 30 and 60 degrees of seismic waves and the Liu and Hong coherency model are considered. Finally, using the anisotropic coherency model of Hao et al. and the propagation angle 45 degree, the three-directional SVEGM is generated, in case 3. Results show that each component of the generated SVEGM records is affected by propagation angle and directional dependency of the coherency model. The second part of the paper is devoted to two-dimensional analyses of Marun earthfill dam and three-dimensional analyses of earthfill dams with different length-to-height ratios subjected to uniform input motion and artificially generated SVEGM.

The impact of increasing femoral offset and stem anteversion on postoperative dislocation in bipolar hemiarthroplasty.

Femoral offset and anteversion have been reported to affect the incidence of dislocation following bipolar hemiarthroplasty, although the magnitudes of contributions of the femoral offset and stem anteversion on dislocation, both singly and in combination is not fully understood. Using the CT data of 61 patients (61 hips), including 30 male and 31 female who underwent bipolar hemiarthroplasty, three-dimensional dynamic motion analysis was performed using a modular implant that enabled adjustment of femoral offset and stem anteversion independently. The pattern of impingement and relationship between femoral offset/stem anteversion and range of motion were evaluated using the software. We found that a higher femoral offset and stem anteversion correlate with a greater range of motion of flexion and internal rotation. Furthermore, an increased femoral offset has a great effect on increasing range of motion of flexion than stem anteversion, and increased both femoral offset and stem anteversion have fewer effect on the flexion, whereas increasing stem anteversion has a great impact on internal rotation than offset, especially in the case with lower femoral anteversion. However, a higher stem anteversion decrease the range of motion of external rotation, whereas a higher femoral offset leads to an increased range of motion of external rotation. We demonstrated that both a higher femoral offset and stem anteversion substantially affected the range of motion in flexion, internal rotation and external rotation. However, these are not independent, but rather mutually confounding, the surgeons should consider retaining femoral/anterior offset in bipolar hemiarthroplasty.

Research on anchor damage and protection of three-core composite submarine cable considering impact angle

Submarine cables are important equipment in many power engineering and communication engineering projects. However, power transmission and signal transmission is threatened by anchors hitting submarine cables. Due to the nature of the helical structure of the cable, different angles of impact have different effects on submarine cable damage. In this paper, a three-dimensional dynamic response analysis model, “ship anchor – three-core composite submarine cable – soil”, is developed based on ABAQUS to study how the impact angle of ship anchors influences the damage to submarine cables. It explores the damage to cables struck by anchors of different weights and at different speeds. The longitudinal compression rates of conductors and the optical fibre units of submarine cables at different burial depths are obtained and advice for the protection of cables is provided. The results show that anchor speed has a greater impact on cable damage than anchor mass. The impact angle on cable conductors and the optical fibre units decreases as the depth of burial increases. A burial depth greater than 1.9 times the cable diameter provides a protective effect on the submarine cable.

A smartphone-assisted down/up-conversion dual-mode ratiometric fluorescence sensor for visual detection of mercury ions and l-penicillamine

Establishment of a rapid, sensitive, visual, accurate and low-cost fluorescence detection system to detect multiple targets was of great significance in food safety evaluation, ecological environment monitoring and human health monitoring. In this work, a smartphone-assisted down/up-conversion dual-mode ratiometric fluorescence sensor was proposed based on metal-organic framework (NH2-MIL-101(Fe)) and CdTe quantum dots (CdTe QDs) for visual detection of mercury ions (Hg2+) and L-penicillamine (L-PA), in which NH2-MIL-101(Fe) was used as the reference signal and CdTe QDs was used as the response signal. The down-conversion fluorescence system at excitation wavelength of 300 nm (ex: 330 nm) was used to detect Hg2+ and L-PA, in which the detection limit of Hg2+ was 0.053 nM with the fluorescence color changed from green to blue, and the detection limit of L-PA was 1.10 nM with the fluorescence color changed from blue to green. Meanwhile, the up-conversion fluorescence system at excitation wavelength of 700 nm (ex: 700 nm) was used to detect Hg2+ and L-PA. The detection limits of Hg2+ and L-PA were 0.11 nM and 2.93 nM, respectively. The detection of Hg2+ and L-PA were also carried out based on the color extraction RGB values identified by the smartphone with a detection limit of 0.091 nM for Hg2+ and 8.97 nM for L-PA. In addition, the concentrations of Hg2+ and L-PA were evaluated by three-dimensional dynamic analysis in complex environments. The smartphone-assisted down/up-conversion dual-mode ratiometric fluorescence sensor system provides a new strategy for detection Hg2+ and L-PA in food safety evaluation, environmental monitoring and human health monitoring.

Methodology to Analyse Three-Dimensional Asymmetries in the Forces Applied to the Pedals in Cycling

The asymmetries study between both legs of the forces applied to the pedals in cycling is important because they may affect the performance of the cyclist or prevent the occurrence of injuries. Studies focused on analysing asymmetries in forces tend to consider only the effective force, disregarding the three-dimensional nature of the force. Furthermore, these studies do not analyse the possible physical or neurological causes that may have led to the appearance of the asymmetries. This paper presents a methodology to carry out three-dimensional analysis of the asymmetries of the forces applied in both pedals and discriminate the possible sources of these asymmetries. Seven participants, amateurs and without pathologies, were analysed. Two commercial pedals were instrumented to measure the three components of the force applied to each pedal. The Normalized Symmetry Index (NSI) and the Cross Correlation Coefficient (CCC) were used for the asymmetries analysis. Results showed that both indexes need to be used in conjunction to analyse the causes of asymmetry in the pedal forces from a 3D perspective along the pedal cycle. The NSI is an index that makes it possible to evaluate asymmetry by considering only the value of the force applied by each leg at each instant. The CCC makes it possible to evaluate whether the temporal evolutions of the forces applied by each leg are similar. Preliminary results suggest that the proposed methodology is effective for analysing asymmetries in the forces in a pedalling cycle from a three-dimensional point of view. Forces in the sagittal plane showed a high level of symmetry. The lateral-medial force presented the highest level of asymmetry due to the difference in the magnitudes of the applied forces by both legs and the existing time shift between the two force patterns. The results of this work will allow for more complete and accurate three-dimensional dynamic analyses of the lower body during pedalling.

A comprehensive approach for bridge performance evaluation under rockfall impact integrated with geological hazard analysis

Rockfall is one kind of major hazard that seriously threatens the safety of bridge structures passing through mountainous areas. The complexity of geological conditions in mountainous areas makes it difficult to determine the initial impact parameters of falling rock in the bridge performance analysis. At present, the subjective and deterministic methods are adopted to get the initial motion parameters of the falling rock for evaluating the structural responses. In this paper, the probability distributions of falling rocks collision parameters are obtained by the rockfall Monte Carlo simulations. Then the characteristic values from the probability distribution of rock motion parameters are taken as the input parameters in the dynamic simulation of bridge structure. Finally, three-dimensional nonlinear dynamic analysis is employed to evaluate the safety of the bridge structure under rockfall hazards. The residual resistance index (RRI) is presented for quantifying the post-impact performance of bridge pier and girder under rock collision. The structural safety is mainly dominated by the impact mass and translational velocity of the falling rock rather than the rotational velocity and impact angle. The rock shape also has non-negligible influence on the structural dynamic responses and performance, and the cube-like rock induces more severe structural damage than other shapes. According to the RRI and probability distribution of rock mass, the non-exceedance probability of RRI is obtained which can be used for the risk analysis of rockfall impacting on bridges. The proposed comprehensive approach for bridge performance evaluation considers the uncertainty of rockfall characteristics, and it provides more reasonable solution to investigate the impact performance of bridge structure under rockfall disasters.

Three-Dimensional Dynamic Modeling and Motion Analysis of a Fin-Actuated Robot

Dynamic modeling has beencapturing the attention for its fundamentality in precise locomotion analyses and control of underwater robots. In this article, we focused on the 3-D dynamic modeling and the experimental validation of multiple motion patterns of underwater robots in large-scale parameter space. A 3-D dynamic model of an active-tail-actuated robotic fish with a barycentre regulating mechanism was first built by combining Newton’s second law for linear motion and Euler’s equation for angular motion. Then, the model parameters were determined by 3-D computer-aided design software SolidWorks, HyperFlow-based computational fluid dynamics simulation, and grey-box model estimation method. Finally, both kinematic experiments with a prototype and numerical simulations were applied to validate the dynamic model’s accuracy mutually. Based on the dynamic model, multiple 3-D motions, including rectilinear motion, turning motion, surfacing motion, and spiral motion, were analyzed. The experimental and simulation results demonstrated the effectiveness of the proposed model in evaluating the trajectory, attitude, and motion parameters such as the velocity, turning radius, turning angular velocity of the robotic fish.

Development and Application of a Platform for Multidimensional Urban Earthquake Impact Simulation

Earthquakes can be devastating to cities. Therefore, accurate and efficient simulation of the potential seismic damage to buildings has become an indispensable part of worldwide efforts to mitigate earthquake hazards. Precise simulation results can highlight potential seismic damage and serve as a reference in urban development and for planning post-earthquake rescue operations. In urban areas, simulation of the structural dynamic response during an earthquake is key for planning an appropriate emergency response. Multidimensional visualization of the effects of earthquakes is a popular technique in current earthquake simulation research. In the present study, a dynamic multidimensional simulation method was developed for analyzing the impact of an earthquake on buildings. This method involved conducting three-dimensional (3D) dynamic analysis of data from a seismic capacity database. Polygonal models and seismic capacity data were used in a high-performance computing process to calculate the seismic response of each building in an urban environment. On the basis of the calculations, a platform was developed for multidimensional urban earthquake impact simulation (MDUES). The developed MDUES platform enables analysis of the impact of long-period earthquakes, simulation of the 3D seismic responses of buildings, and visualization of the disaster risk and earthquake impact in a specified area. In summary, simulation of structural seismic responses in an urban setting necessitates a careful examination of the characteristics of ground and building motion, and the results of this simulation can provide a crucial reference for city planning, post-earthquake rescue operations, and seismic damage assessments.