Horizontal Force Components Research Articles

Precise instruction and consideration of the vertical and horizontal force component increases validity and reliability of the 90:20 Isometric Posterior Chain Test.

Hamstring injuries are associated with decreased hamstring strength. Matinlauri et al.'s 90:20 Isometric Posterior Chain Test (90:20 IPCT) efficiently assesses hamstring strength, but has not been validated so far. Furthermore, their rather unprecise original instruction allows high variability in test execution. We added a new instruction and variables and examined, whether this measure leads to increased reliability and validity. We assessed hamstring strength of 23 sport students via the 90:20 IPCT under the original instruction, to exert vertical force, and our new instruction, to exert vertical and horizontal force. Instead of only using bare vertical force as variable under the original (Fz_V) and our new instruction (Fz_VH), we also calculated the resultant force (Fres_VH) and the applied torque onto the force place (M_F_ortho_VH). To test for validity, we correlated the outcome variables with peak torque of gold standard dynamometry. Furthermore, we measured muscle activities of the mm. rectus femoris, biceps femoris, semitendinosus, and gluteus maximus under our new instruction and compared them to those under the original variable (Fz_V) via one sample t-tests. To evaluate reliability, tests were repeated on two separate days, for which we calculated intra class correlation coefficients (ICCs) and coefficients of variation (CVs). Our new instruction and variables (Fz_VH, Fres_VH, M_F_ortho_VH) showed better validity (mean r = 0.77, r = 0.81, and r = 0.85) and equally good or better reliability (ICCs: 0.87, 0.89, and 0.94; CVs: 4.7%, 4.1%, and 4.7%) than the original instruction and variable (Fz_V) (mean r = 0.70; ICC: 0.91; CV: 5.6%). There were no differences in muscle activities between the variables and instructions of the 90:20 IPCT. We recommend our new instruction and the applied torque onto the force plate as it makes the 90:20 IPCT a more reliable and valid tool to assess hamstring strength.

Photospheric Pore Rotation Associated with a C-class Flare from Spectropolarimetric Observations with DKIST

We present high-resolution observations of a C4.1-class solar flare (SOL2023-05-03T20:53) in AR 13293 from the Visible Spectro-Polarimeter (ViSP) and Visible Broadband Imager (VBI) instruments at the DKIST. The fast cadence, good resolution, and high polarimetric sensitivity of ViSP data provide a unique opportunity to explore the photospheric magnetic fields before and during the flare. We infer the magnetic field vector in the photosphere from the Fe i 6302 Å line using Milne–Eddington inversions. Combined analysis of the inverted data and VBI images reveals the presence of two opposite polarity pores exhibiting rotational motion both prior to and throughout the flare event. Data-driven simulations further reveal a complex magnetic field topology above the rotating pores, including a null-point-like configuration. We observed a 30% relative change in the horizontal component (δ F h ) of Lorentz force at the flare peak time and roughly no change in the radial component. We find that the changes in δ F h are the most likely driver of the observed pore rotation. These findings collectively suggest that the back reaction of magnetic field line reconfiguration in the corona may influence the magnetic morphology and rotation of pores in the photosphere on a significantly smaller scale.

Unrestrained Versus Vertically Restrained Loaded Countermovement Jumps: Are There Any Differences in the Components of Force Application?

The objective of this study was to compare a number of variables derived from the vertical and horizontal force components between loaded countermovement jumps performed in a Smith machine (SM modality; vertically restrained jumps) and with free weights (FW modality; unrestrained jumps). Twenty-three recreationally trained individuals, 6 women and 17 men, performed on a 3D force platform 5 maximal countermovement jump trials against 3 external loads (30%, 50%, and 70% of the SM 1-repetition maximum) using the SM and FW jumping modalities on separate sessions. The SM modality promoted greater values for virtually all the variables derived from the vertical force component (maximal force, maximal and minimum velocity, and impulse) and also shorter durations of the braking and propulsive phases. Regardless of the countermovement jump phase (braking or propulsive), the impulse directed toward the backward direction was always considerably greater for the SM compared with the FW modality. These results evidence that for recreationally trained individuals, the SM modality could be more effective to increase the general force capacity of the leg muscles due to increased external stability, while the FW modality is preferable when the orientation of force application is a crucial consideration, as it reduces the horizontal force component.

Insight into the shear failure mechanism of Wound FRP reinforced concrete beams through numerical simulations considering interface damage and material anisotropy

Utilizing the inherent flexibility of high-strength fibres, Fibre-Reinforced Polymers (FRP) can be engineered as optimized reinforcing cages for concrete structures through the application of advanced digital fabrication techniques. However, existing codified design methods and numerical investigations found in the literature fall short in providing an accurate characterization of the actual performance of FRP reinforcement in concrete structures. This work presents a novel Finite Element (FE) modelling approach for concrete beams reinforced with FRP in non-traditional arrangements, accounting for reinforcement-concrete interface behaviour and FRP material anisotropy. Validation against experimental tests of flexible Wound-FRP (W-FRP) reinforced beams demonstrates accurate predictions of load-displacement curves, crack propagation, and load-strain curves. The study delves into shear failure mechanisms, emphasizing FRP reinforcement behaviour and damage evolution at reinforcement-concrete interfaces. Further parametric analysis explores the impact of W-FRP inclination angle and spacing, revealing their significant influence on beam stiffness and ultimate capacity. Specifically, the horizontal tensile force component in inclined links and increased modulus of links with reduced spacing enhance stiffness. Altered crack propagation due to W-FRP patterns, coupled with resulting damage development at concrete-stirrup interfaces and stress evolution in W-FRP stirrups, are key contributors to varied ultimate capacity. Moreover, higher performance of W-FRP stirrups with smaller spacing and reduced cross-section area further bolsters ultimate capacity. This research advances the modelling of FRP-reinforced concrete, offering potential solutions for optimizing FRP material utilization in concrete structures.

Formation characterization and dynamic mechanism of underwater wet wire and arc directed energy deposition

For the first time, the underwater wet wire and arc directed energy deposition (UW-WADED) multi-tracks deposition layers with favorable morphology were obtained. The forming characteristics of single-track UW-WADED were determined through response surface methodology. It was found that the power function curve provided the best fit for the profile of single-track UW-WADED owing to its changing plumpness value. Subsequently, the formation characteristics of multi-track UW-WADED with varying intervals were investigated. The deposition layer exhibited the flattest surface and the least root-mean-square deviation, measuring 321.79 μm when the interval was 8 mm. The dynamic process of UW-WADED was unveiled through X-ray high-speed images, leading to the formulation of UW-WADED droplet force model. As the arc bubble expanded, the horizontal component of the air drag force pointed to the opposite side of the molten pool and was the principal factor for the droplets to become spatters in UW-WADED. The mechanism of the defect formation was also revealed. The accumulation of the molten pool on the previous deposition layer coupled with the downflow of the molten slag were the inducers of slag inclusion defect while the exorbitant molten pool increased the likelihood of molten pool explosion and subsequent spatter formation.

Comparison of the Vertical and Horizontal Components of the Ground Reaction Force of Patients with Anterior Cruciate Ligament Reconstruction and Healthy Individuals during Walking

Introduction: The aim of this research was to compare the vertical, medial-lateral and anterior-posterior components of ground reaction force after anterior cruciate ligament reconstruction with the healthy individuals during walking.
 Methods: This was an analytic cross sectional research. The participants of this research included 46 football and volleyball athletes, who were divided into two groups of individuals with anterior cruciate ligament reconstruction (ACLR) and healthy individuals. A force plate was employed to evaluate the components of the ground reaction force while walking.The data were statistically analysed using independent t test and SPSS version 16 software.
 Results: The results related to the vertical component of ground reaction force showed that the participants with anterior cruciate ligament reconstruction applied more force to the ground during heel strike and toe-off compared to healthy individuals, although the difference between the two groups was not significant (p=0.09 and p=0.35), but this difference was greater during heel strike. Likewise, the results related to the horizontal components of the ground reaction force showed that participants with anterior cruciate ligament reconstruction applied more force to the ground in all horizontal components of the ground reaction force, but the biggest difference between the two groups was in the first 20% of the stance phase and in the posterior (p<0.007) and lateral (p<0.02) directions. This difference between the two groups was significant.
 Conclusion: The results of the research showed that the most important difference between the two groups occurred in the first 20% of the stance phase. Although among the 6 measured components, only the posterior (p < 0.007) and medial (p < 0.02) ground force components were significant.

Monitoring of structures with bearing elements in the form of long vertical rods

A building structure is considered, which in the design form consists of two vertical rectilinear interacting elements. One of them is loading, the other is carrying. The bearing element is presented in the form of a long thin rod loaded with an external axial vertical force. Due to the errors of geodetic verification and installation work, the bearing rod will be installed with some inclination and displacement relative to the coordinate axes. The external load on the bearing element is represented by the force vector, which is equivalent to the loading rod. Errors of geodetic verification and installation work will change the design direction of the force line and its design position on the supporting element. An inclined force vector will have a vertical and horizontal force component. Thus, the line of action of the loading force and the longitudinal axis of the supporting rod will be located at an angle to each other, which will cause bending momentsand transverse forces in the sections of the rod. A design "changed" in relation to the project is created. Bending moments and horizontal forces in this design will contribute to premature bending of the rod. An unevenly heated rod also acquires the ability to distort. The influence of the specified factors can be increased, and the stability of the rod significantly weakened due to uneven subsidence, horizontal displacement or tilting of the supporting structure due to dangerous exogenous geological processes. Therefore, errors in the position of elements, changes in temperature, geological processes disrupt the linear form of equilibrium of the bearing rod and its position in space. The change in shape and relative position contributes to the premature emergence of an unstable state under an increasing external load. In the changed design, the bearing rod may suddenly find itself in a critical stress-deformed state. The task of monitoring is to sense and properly record changes and dynamics of the stress-strain state. For this purpose, measuring complexes with a certain configuration are designed, which provide with the necessary specified accuracy the measurement of changes in the physical state of the elements of building structures.

Rapid acoustofluidic mixing by ultrasonic surface acoustic wave-induced acoustic streaming flow

Ultrasonic surface acoustic wave (SAW)-induced acoustic streaming flow (ASF) has been utilized for microfluidic flow control, patterning, and mixing. Most previous research employed cross-type SAW acousto-microfluidic mixers, in which the SAWs propagated perpendicular to the flow direction. In this configuration, the flow mixing was induced predominantly by the horizontal component of the acoustic force, which was usually much smaller than the vertical component, leading to energy inefficiency and limited controllability. Here, we propose a vertical-type ultrasonic SAW acousto-microfluidic mixer to achieve rapid flow mixing with improved efficiency and controllability. We conducted in-depth numerical and experimental investigations of the vertical-type SAW-induced ASF to elucidate the acousto-hydrodynamic phenomenon under varying conditions of total flow rate, acoustic wave amplitude, and fluid viscosity conditions. We conducted computational fluid dynamics simulations for numerical flow visualization and utilized micro-prism-embedded microchannels for experimental flow visualization for the vertical SAW-induced ASF. We found that the SAW-induced vortices served as a hydrodynamic barrier for the co-flow streams for controlled flow mixing in the proposed device. For proof-of-concept application, we performed chemical additive-free rapid red blood cell lysis and achieved rapid cell lysis with high lysis efficiency based on the physical interactions of the suspended cells with the SAW-induced acoustic vortical flows. We believe that the proposed vertical-type ultrasonic SAW-based mixer can be broadly utilized for various microfluidic applications that require rapid, controlled flow mixing.

Numerical modeling of the long surface wave impact on a partially immersed structure in a coastal zone: Solitary waves over a flat slope

This paper describes the numerical simulation of the solitary wave impact on a partially immersed and fixed structure located over a flat coastal slope. This topic is related to the need for assessment of the possible impact of long waves, such as tsunamis, on partially immersed structures in coastal waters. Numerical algorithms on a movable grid adapting to the motion of the shore point are developed for a fully nonlinear dispersive model and a dispersionless shallow water model. Their validation is carried out by comparing the obtained solutions with the data from laboratory experiments and with the results obtained using a fully nonlinear potential flow model. The study shows that the difference between the maximum wave impact on the body at the foot of the slope and near the shore can be up to 6 times. In many cases, the maximum horizontal component of the wave force occurs under the influence of the wave reflected from the shore, indicating the need to consider the influence of the shore-reflected wave when assessing the impact of long waves on structures located in coastal waters. Furthermore, the need to use runup algorithms instead of reflective boundary conditions (vertical wall) has been identified for gentler slopes, where the differences in the wave impact for these two configurations can be 2–3 times.

Prediction Of The Coefficient Of Friction In The Single Point Incremental Forming Of Truncated Cones From A Grade 2 Titanium Sheet

The aim of this paper is to analyze the effect of the process parameters on the coefficient of friction (COF) in the single-point incremental forming process. This investigation may be useful for further FEM analyses where the tool-workpiece contact must be set appropriately to obtain adequate results. The friction was analyzed between a solid tungsten carbide ⌀8 hemispherical ended tool with a radius of 4 mm and a grade 2 pure titanium sheet. As a lubricant, 10W40 engine oil was used. The experiment was of a central composite design and 20 runs in random order were carried out. The influence of input factors, namely spindle speed, tool feed and incremental step depth, was analyzed for the COF response. Two type of equations founded in the literature have been acquired to calculate COF values. An investigation of COF analysis was done for initial tool contact, the first tool full depth contact and stabilized forming region. Additionally, single components of the horizontal force (X-axis and Y-axis) were taken into account. Analysis of variance shows that there is no correlation between the input factors and the COF responses. However, the mean model fitted to the results obtained allows for the prediction of the COF by using the vertical force component and only one horizontal force component. The resulting mean value of the COF between the tool and the workpiece equals 0.4 for Eq. (1) initial contact, stabilized forming: Eq. (1) 0.656 and Eq. (2) 0.469.

Construction Technology of Mixed Support for Starting Section of Concrete Box Arch

In the construction of the starting section of a concrete arch bridge spanning ravines or deep water, technical problems such as the inability to adopt full-stent construction, resulting in low construction efficiency. In response to this problem, this paper relies on the Shatuo Bridge in the deep-water area near cliff and proposes the use of a steel pipe support and a hybrid bracing technology to construct the starting section of the arch bridge, that is, using a steel pipe bracket near the arch foot. Cast-in-situ construction and horizontal force components are provided by diagonal cables and steel beams are embedded in the arch seats to balance the horizontal loads on the supports. The rest of the beam sections that cannot be erected with steel pipe supports are constructed by using inclined anchors. The practice shows that this technology successfully overcomes the limitation of the construction work space, and achieves the purpose of reducing costs and shortening the construction period. And the method can provide reference for the construction design of similar structures.

Optimization of CMT Characteristic Parameters for Swing Arc Additive Manufacturing of AZ91 Magnesium Alloy Based on Process Stability Analysis.

The droplet transfer behavior and stability of the swing arc additive manufacturing process of AZ91 magnesium alloy based on the cold metal transfer (CMT) technique were studied by analyzing the electrical waveforms and high-speed droplet images as well as the forces on the droplet, and the Vilarinho regularity index for short-circuit transfer (IVSC) based on variation coefficients was used to characterize the stability of the swing arc deposition process. The effect of the CMT characteristic parameters on the process stability was investigated; then, the optimization of the CMT characteristic parameters was realized based on the process stability analysis. The results show that the arc shape changed during the swing arc deposition process; thus, a horizontal component of the arc force was generated, which significantly affected the stability of the droplet transition. The burn phase current I_sc_wait presented a linear function relation with IVSC, while the other three characteristic parameters, i.e., boost phase current I_boost, boost phase duration t_I_boost and short-circuiting current I_sc2, all had a quadratic correlation with IVSC. A relation model of the CMT characteristic parameters and IVSC was established based on the rotatable 3D central composite design; then, the optimization of the CMT characteristic parameters was realized using a multiple-response desirability function approach.

Feasibility of submerged floating tunnel with polygonal cross-sections — investigation from a viewpoint of submarine slide hazards

Recently, submerged floating tunnels have generated a lot of interest due to their unique cross-water traffic benefits. However, the destructive threat of submarine slide hazards was not fully considered in the design scheme of submerged floating tunnels, in particular to the feasibility of applying various cross-section forms on land to submerged floating tunnels under that hazard influence. This study mainly investigates the load effect of submerged floating tunnels with polygonal cross-sections (comprising three types: square, hexagon, and octagon) under the impact of submarine slides, via a computational fluid dynamics (CFD) approach. Results show that the impact forces produced by submarine slides on submerged floating tunnels are significant (e.g., submarine slides with a velocity of 4 m/s may produce a force level near 1×105 N/m), where the horizontal impact force components should be given priority consideration based on the general working environment of submerged floating tunnels. Compared with typical circle tunnels, polygonal tunnels suffer higher impact forces, and the polygonal types with fewer edges show a greater impact force. Finally, a simplified force evaluation approach for the submerged floating tunnel with polygonal cross-sections is proposed for guiding the relevant engineering design.

Investigation of the strut‐and‐tie model of a single‐plane cable‐stayed bridge tower under vertical component of the cable force

AbstractThe design of reinforcement of concrete pylons in cable‐stayed bridges is a challenging task. Usually, only the influence of the strong horizontal component of the cable force is considered during the reinforcement design of the concrete tower, while the bursting forces caused by the vertical components of the cable forces are ignored. However, the latter is also an important factor for concrete cracking in bridge towers. In this paper, the concrete tower of a single cable plane cable‐stayed bridge is considered. The strut‐and‐tie model (STM) of the pylon wall subject to the vertical components of one single cable force was derived. Based on the minimum strain energy principle, an equation for predicting the bursting force was given. Then, the STMs of a concrete pylon with two cable forces with different vertical distances between cables were proposed. A series of equations for predicting the bursting force in different STMs were presented. The STMs of a concrete pylon with multiple cables were subsequently obtained from the STM for two cable forces. The analysis results show that the vertical distance between cables has a great influence on the STM configuration of the tower. When the cable distance is less than 0.7 times the width of the tower wall, the bursting force is larger than that when the cable distance is larger than 0.7 times the width of the tower wall. This study was expected to provide a reference in the design and applications of pylons of concrete cable‐stayed bridges.

Acoustofluidic separation of proteins from platelets in human blood plasma using aptamer-functionalized microparticles.

Microfluidic liquid biopsy has emerged as a promising clinical assay for early diagnosis. Herein, we propose acoustofluidic separation of biomarker proteins from platelets in plasma using aptamer-functionalized microparticles. As model proteins, C-reactive protein and thrombin were spiked in human platelet-rich plasma. The target proteins were selectively conjugated with their corresponding aptamer-functionalized microparticles of different sizes, and the particle complexes served as a mobile carrier for the conjugated proteins. The proposed acoustofluidic device was composed of an interdigital transducer (IDT) patterned on a piezoelectric substrate and a disposable polydimethylsiloxane (PDMS) microfluidic chip. The PDMS chip was placed in a tilted arrangement with the IDT to utilize both vertical and horizontal components of surface acoustic wave-induced acoustic radiation force (ARF) for multiplexed assay at high-throughput. The two different-sized particles experienced the ARF at different magnitudes and were separated from platelets in plasma. The IDT on the piezoelectric substrate could be reusable, while the microfluidic chip can be replaceable for repeated assays. The sample processing throughput with the separation efficiency >95% has been improved such that the volumetric flow rate and flow velocity were 1.6 ml/h and 37 mm/s, respectively. For the prevention of platelet activation and protein adsorption to the microchannel, polyethylene oxide solution was introduced as sheath flows and coating on to the walls. We conducted scanning electron microscopy, x-ray photoemission spectroscopy , and sodium dodecyl sulfate- analysis before and after the separation to confirm the protein capture and separation. We expect that the proposed approach will provide new prospects for particle-based liquid biopsy using blood.

Rotation Capacity of I-Shaped Beam Failed by Local Buckling in Buckling-Restrained Braced Frames with Rigid Beam-Column Connections

A buckling-restrained braced frame (BRBF) reduces the response of buildings during a strong earthquake, during which the surrounding members such as beams and columns must resist the axial force imposed by the buckling-restrained braces (BRBs). However, the steel beams and columns are subjected to reversed axial force from the horizontal and vertical component of BRB axial force. The steel beams might then buckle under the compressive force or even yield under the subsequent tensile axial force because the beams are not designed primarily to sustain the axial force. Therefore, the rotation capacity becomes inconsistent with the typical loading protocols. Faced with this concern, this study examines a BRBF design with reasonable balance between the steel frame and the BRBs. Pushover analyses and nonlinear response history analyses (NRHAs) are undertaken to quantify the magnitude of the beam axial force. Furthermore, a detailed finite-element analysis (FEA) model is constructed based on results obtained from a previous experiment. The strain distribution and axial force transfer mechanism are identified using an experimentally validated FEA model. Results confirm that BRB axial force is transmitted primarily to the single side of the flange. Furthermore, the parametric study in terms of the beam section, BRB axial force, and loading protocols establishes a database of the structural performance. The results of this research are used to formulate a novel index and equations describing the ultimate strength ratio, rotation capacity, and energy dissipation capacity.

Inverse modeling and experimental validation for reconstructing wave sources on a 2D solid from surficial measurement

This paper discusses a source inversion method for the reconstruction of moving or stationary wave sources on the top surface of a two-dimensional (2D) linear elastic solid. This adjoint-gradient-based source inversion method uses vibrational measurements from sensors at the top surface of the solid, which can be heterogeneous and damped, to reconstruct temporal and spatial distributions of the wave sources. The finite element method (FEM) is used to obtain wave solutions with the high-resolution discretization of source functions in space and time leading the number of inversion parameters to range in the millions.Numerical experiments, in which the iterative inversion procedure begins with an initial guess of zero loading at all points in space and time, show that the presented approach is effective at reconstructing horizontal and vertical components of force (i.e., normal and shear tractions) for multiple simultaneous moving dynamic distributed loads without any prior knowledge about the loads except that all loading is applied along the top surface of the solid. Provided that moving loads on roadways are applied to the top surface, it is shown that updating the guessed loading at just surface nodes, rather than at all nodes in space, greatly improves the inversion results. The inversion is shown to be as effective at reconstructing loads on the top surface of a solid when the solid is horizontally layered with multiple materials as when the solid it is homogeneous. Reducing the distance between sensors improves the accuracy of the inversion while reducing the width of distributed loads leads to less accurate results. The authors also validate the presented inversion method by using experimental data obtained from lab-scale tests at a high frequency (100 kHz) for a stationary load on a homogeneous solid.

Radiation forces on a Mie particle in the evanescent field of a resonance waveguide structure.

Evanescent waves of a guided mode carry both momentum and energy, which enables them to move small objects located on a waveguide surface. This optical force can be used for optical near-field manipulation, arrangement, and acceleration of particles. In this paper, using arbitrary beam theory, the optical force on a dielectric particle in the evanescent wave of a resonance waveguiding structure is investigated. Using Maxwell's equations and applying the boundary conditions, all the field components and a generalized dispersion relation are obtained. An expression for the evanescent field is derived in terms of the spherical wave functions. Cartesian components of the radiation force are analytically formulated and numerically evaluated by ignoring the multiple scattering that occurs between the sphere and plane surface of the structure. Our numerical data show that both the horizontal and vertical force components and the forward particle velocity are enhanced significantly in the proposed resonance structure compared to those reported for three-layer conventional waveguides. Exerting stronger force on macro- and nanoparticles can be very useful to perform advanced experiments in solutions with high viscosity and experiments on biological cells. In addition, this resonance planar structure can be mounted on an inverted optical microscope stage for imaging the motion of nanoparticles especially when the particle collides and interacts with objects.

Data Analysis for Dynamics of Cooperative Bridge-Vehicle System Considering Pavement Roughness and Separation

A radial nonlinear multi-spring-damper tire (RNMST) model is proposed in this paper for dynamics behavior analysis of the cooperative bridge-vehicle (CBV) system by considering different road surface roughness and separation. First, both the finite element (FE) and force analysis of the RNMST model were analyzed and studied under different velocity and different class of road surfaces. The three types of tire models, nonlinear single-spring tire (NSST) model, nonlinear multi-spring tire model and RNMST model, were introduced as the vehicle tire devices for a quarter vehicle models into nonlinear cooperative bridge-vehicle system. The cooperative dynamics problem, alongside separation and the responses of road surface in terms of its uneven nature, is a typical dynamics problem with the nonlinearity of material which can be solved using the Newmark- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> method. The comparison of the results demonstrated that the analysis of the dynamics of the cooperative bridge-vehicle system under the RNMST model and NMST model are generally similar. However, the radial nonlinear multi-spring-damper tire model is more accurate and closer to the stress state of the real tire model. Also, to further illustrate the comprehensive performance of the RNMST, the responses under different pavement excitations were analyzed by using the amplitude-frequency spectrum method. Finally, to research the influence dynamics of tire force on the CBV system, the horizontal component of tire force was analyzed. This is conducive to numerical research of the dynamic responses of both the bridge and the vehicle.

Shear performance of prismatic and tapered beams with corrugated steel webs under external prestressing force

This paper analyzes the shear performance of prismatic and tapered beams with corrugated steel webs (CSWs) under different layouts of external prestressing based on finite element (FE) simulations. The results show that when the external prestressing tendon distribution is straight, there is no shear stress in the prismatic beam with CSWs, but there is shear stress in the tapered beam with CSWs. Therefore, it is not generally accurate that only the vertical component of the external prestressing force can induce shear stress when calculating the shear stresses caused by external prestressing in the existing design specifications. In theory, it is proven, for the first time, that the axial force and prestressing bending moment generated by external prestressing will generate additional shear stresses, which will cause the shear stress redistribution in tapered beams with CSWs. However, these two factors were not taken into account in existing design specifications, which resulted in a significant error in predicting the shear stress for tapered beams with CSWs when ignoring the contribution of the axial force and prestressing bending moment. Consequently, a unified analytical formula is proposed for predicting the shear stresses caused by an external prestressing force on the CSW, and this formula can be appropriate for both tapered and prismatic beams with CSWs under both straight and bent external prestressing tendons. In addition, this study quantitatively investigates the ratios of shear stresses in the CSWs induced by the vertical and horizontal components of the external prestressing force, and their corresponding bending moments. Finally, the study reveals the factors affecting the distribution of shear stress on beams with CSWs under external prestressing and proves that using the traditional method to calculate the shear stress neglects the shear capacity of the inclined concrete bottom slab will produce a significant error when applied to tapered cases.