Abstract Accounting for fluid-solid coupling in saturated underwater soils, the scattering problem of underwater tunnel under plane SV-wave incidence is investigated by using the Fourier-Bessel series expansion method of wave function. Numerical examples analyze the effects of incident wave angle, frequency, tunnel burial depth, and porosity on displacement at the water-soil interface and dynamic stress concentration on the tunnel surface. When η=0.5, increasing the incident angle reduces horizontal displacement by up to 39.3%, increases vertical displacement by up to 96.2%, and raises the Dynamic Stress Concentration Factor (DSCF) on the tunnel surface by 65.6%. Porosity shows minimal impact on stress and displacement. As porosity increases, horizontal displacement decreases by up to 2.1%, vertical displacement increases by approximately 1.23%, and DSCF decreases by 1.2%. As incident frequency increases, displacement and stress distributions become more complex, with more pronounced peaks, and troughs. Maximum horizontal displacement increases by 86.4%, and vertical displacement by 91.2%. Displacement and stress concentration are most pronounced above the tunnel under shallow burial conditions. fluidsolid fluid solid soils SVwave SV FourierBessel Fourier Bessel function depth watersoil water soil η05 η 0 5 η=0.5 393 39 3 39.3% 962 96 2 96.2% (DSCF 656 65 6 65.6% 21 1 2.1% 123 23 1.23% 12 1.2% complex peaks troughs 864 86 4 86.4% 912 91 91.2% conditions η0 η=0. 39.3 9 96.2 65.6 2.1 1.23 1.2 8 86.4 91.2 η=0 39. 96. 65. 2. 1. 86. 91. η=

Abstract In this paper, the penetration resistance of 6061 aluminum plates to explosively formed projectiles (EFPs) at the incidence angles of 0°, 15°, 30°, and 45° was studied. The penetration process was roughly divided into three typical stages—the plastic flanging stage of the target, the righting stage of the projectile, and the plug formation stage of the target. Through the energy analysis, the energy consumption of the aluminum plate increased with the increase in the incidence angle during the entire penetration process. Through the microscopic analysis of the perforated wall surface of the aluminum plate, it was found that there were distinct boundaries and differences between the plastic reaming zone and the punching plug fracture zone.. Overall, four kinds of classification modes were proposed for the damage of the aftereffect plate, which provides a method to evaluate the aftereffect of EFP oblique penetration into 6061 aluminum plates. paper 606 EFPs (EFPs 0 0° 15 15° 30 30° 45 studied stagesthe stages target projectile zone. Overall 60 1 3 4 6

Abstract To further improve the strike accuracy and penetration power of explosively-formed projectile (EFP) after long-distance flight, a polygonal charge capable of forming EFP with tail fins was designed during the study. A model for calculating the EFP velocity was derived from the effective charge and detonation projection theories with the integration of calculus. The circumferential velocity distributions of EFP formed using polygonal charges were obtained using this model, and the mechanisms underlying the formation of tail fins were elucidated. The feasibility of using this polygonal charge to form tail fin EFP was verified by conducting multi-media soft recovery tests and numerical simulations. Furthermore, the feasibility of forming tail fin EFP using polygonal charges with different numbers of sides and the effects of the structural parameters of a hexagonal charge on the formation of tail fin EFP were investigated by simulation. The ranges of optimal values for the structural parameters of a hexagonal charge capable of forming high-performance tail fin EFPs were determined. explosivelyformed explosively (EFP longdistance long distance flight study calculus elucidated multimedia multi media simulations Furthermore simulation highperformance high performance determined

Abstract Based on the inverse piezoelectric effect and other characteristics of piezoelectric ceramics, a new type of piezoelectric variable friction damper is developed, and the output performance test of piezoelectric ceramic actuator and piezoelectric variable friction damper is carried out, and the parametric mechanical model of the damper is established by using Simulink to carry out numerical simulation, and compared and analyzed with the test results. The results of the study show that the simulation and the test present a good regular agreement. With the increment of loading voltage, the displacement deformation and zero-displacement thrust of piezoelectric ceramic actuator are approximately linear with the loading voltage; when the loading voltage is increased by 15V every time, the test value of the output damping force of the damper increases by 259.66N on average step by step, and the simulated value increases by 256.14N step by step, and the damping force has a linearly incremental relationship with the voltage and the slope of the linear increase is 16.434. ceramics developed agreement zerodisplacement zero V time 25966N N 259 66N 25614N 256 14N 16434 16 434 16.434 25 1643 1 43 16.43 2 164 4 16.4 16.

Abstract This work introduces a new family of strain tensors based on the hyperbolic sine function: The Generalized Hyperbolic Sine (GHS). This family is obtained by using any given strain measure as an argument in a normalized hyperbolic sine function. Particularly, this paper adopts the Seth-Hill family as an argument and shows how some drawbacks of the classical strain measures can be overcome by means of the proposed strain family. A broad analytical study of pure deformation modes (simple axial extension, equi-biaxial loading and simple shear) is presented to show the behavior of the proposed strain family and investigate the physical coherence of their responses. Obtained results are promising as the GHS family proved itself capable of enhancing the physical behavior of the Seth-Hill strain measures and providing versatility with the addition of just one material constant with clear physical meaning. Materials investigated in the article are isotropic and homogeneous. The proposed Hookean-type hyperelastic models can be applied for both incompressible and compressible materials without additional strain energy density function changes. GHS. . (GHS) Particularly SethHill Seth Hill extension equibiaxial equi biaxial shear responses meaning homogeneous Hookeantype Hookean type changes (GHS

Abstract Slender reed straws in nature can withstand heavy weight of reed spikes and lateral wind force, and thus show good mechanical properties, especially compression resistance and shear resistance. In the paper, the quasi-static and dynamic mechanical properties of reed straws were studied. Three influencing factors of the straws were set according to the nodes (node-containing, node-free), location section (location 1, 2, 3, 4, 5), and moisture content (low, medium, high). The tensile strength of node-free reed straws with low moisture content ranged from 55.40 to 68.14 MPa at different locations. The axial compressive strength of node-containing straws was higher than that of node-free straws, and the influence of moisture content on the axial compressive strength was more obvious. The radial compressive strength of node-containing straws is 13.00 times higher than that of node-free straws in the corresponding part. The bending strength of straws gradually increases from the top to the root, and it is further enhanced with higher moisture content. The axial impact peak load of node-containing straws is up to 1.27 times that of node-free straws, and the axial impact peak load of straws with high moisture content is 1.40 times higher than that of straws with low moisture content in the corresponding part. The radial impact strength of reed straws gradually increases from the top to the root. In terms of bending impact strength, the impact toughness of reed straws ranges from 0.030 to 0.14 J·cm2, and the specific energy absorption ranges from 1.09 to 4.35 J/kg. Because of the excellent mechanical properties, reed straws provide important material performance data for the engineering field and inspire the design of new engineering materials or structures by improving strength and reducing weight. force paper quasistatic quasi static studied nodecontaining, nodecontaining node containing, containing (node-containing nodefree, nodefree free , node-free) 1 2 3 4 5, 5 5) low, (low medium high. . high) 5540 55 40 55.4 6814 68 14 68.1 locations obvious 1300 13 00 13.0 part root 127 27 1.2 140 1.4 0030 0 030 0.03 014 0.1 Jcm2 Jcm J cm2 cm J·cm2 109 09 1.0 435 35 4.3 Jkg kg J/kg 554 55. 681 6 68. 130 13. 12 1. 003 03 0.0 01 0. J·cm 10 43 4.

Abstract This paper presents the uncoupled anisotropic thermoelasticity formulation for Boundary Element using the Dual Reciprocity Method. The proposed formulation demands two interpolation functions, one for the particular solution of the elastic problem and another to interpolate the derivatives of the thermal field. For the last one, the shape parameter of multiquadric Radial Basis Functions (RBF) was demonstrated to be a problem to be solved. Some polyharmonic RBFs were tested and a modified function was proposed. Singularity at derivatives of some functions made them impossible to be used and some of them demonstrated great sensibility to saturation. The use of internal points was mandatory under temperature fields irregularly distributed. Few polyharmonic functions were suitable to be used for thermoelasticity and low order functions presented reliable solutions, with the proposed modified RBF presenting slightly better performance over the previously used function. Method field (RBF solved saturation distributed solutions

Abstract The results of finite element analysis of reinforced concrete Vierendeel sandwich plates (RCVSP) using beam-plate elements calculation model show a significant discrepancy with the actual results. Considering the structural characteristics of RCVSP and the calculation method of beam-elements, the assumption of the existence of nodal stiffness domain effects (NSDE) is proposed for its beam-plate elements calculation model. In order to verify this assumption, the existing experimental data of RCVSP is used to compare with the finite element analysis results of the beam-plate elements calculation model. The analysis results show that there is NSDE in the finite element analysis of RCVSP using beam-plate elements calculation model. The beam-elements calculation model FeaR1, which fully considers NSDE, can effectively restore the calculated stiffness lost. Compared with the solid-elements calculation model of RCVSP, the calculation model FeaR1 is more convenient for modeling, enhances computational efficiency, achieves the stiffness restoration rate of approximately 80%, and maintains the average error of no more than 16%. (RCVSP beamplate beam plate beamelements, beamelements elements, (NSDE FeaR lost solidelements solid modeling efficiency 80 80% 16 16% 8 1

Abstract The integration of textile-reinforced concrete (TRC) and reinforced concrete (RC) has recently emerged as a promising strategy for developing hybrid structures. This study examines the flexural and shear behavior of a hybrid deck combining TRC-integrated formwork and RC through 3-point and 4-point bending tests on eight specimens with aspect ratios (a/d) ranging from 1.6 to 2.9. The test results show that the TRC integrated formwork, with its customizable cross-section and strong load-bearing capacity, is ideal for bridge deck structures. Its cracking load exceeds the required construction strength. Furthermore, the TRC formwork enhances load-carrying capacity, stiffness, and ductility, serving as an effective shear connector between concrete layers. The hybrid deck specimens display minimal, fine cracks, indicating enhanced crack resistance, improved serviceability, and reduced crack occurrence. Shear compressive and diagonal shear failures were noted in specimens, but the TRC formwork successfully averted transverse cracks at the interface, ensuring enhanced interfacial bond strength and structural integrity. textilereinforced textile (TRC (RC structures TRCintegrated 3point point 3 4point 4 a/d ad d (a/d 16 1 6 1. 29 2 9 2.9 crosssection cross section loadbearing bearing capacity Furthermore loadcarrying carrying stiffness ductility layers minimal resistance serviceability occurrence interface integrity 2.

Abstract A structural analysis of framed structures using the finite element method considering both the Bernoulli- Euler and the Timoshenko beam theories can be performed adopting cubic interpolation functions that yield analytical solutions for the displacements. However, these theories may not provide stress results with sufficient accuracy. In such cases, it is necessary to employ higher order beam formulations, that may require a high level of discretization. Therefore, this study proposes an enhanced Reddy beam element, obtained by considering interpolation functions calculated directly from the solution of the differential equation system. This solution minimizes the impact of structural discretization on the analysis, and framed structures can be effectively modeled considering the minimum number of elements required to describe the geometry. The results obtained by the proposed formulation were compared against classical beam theories and the Reddy beam model adopting conventional shape functions, showing the efficacy of the proposed element in simulating the elastic behavior of framed structures in a FEM-like procedure. Bernoulli displacements However accuracy cases formulations Therefore system geometry FEMlike FEM like procedure

Abstract Fast calculations are widely required in the traditional applications and the emerging digital twin fields. For those considerations, a novel physics-based fast algorithm, namely generalized rotation-superposition method, is proposed for fast calculating linear elastic responses of generalized rotationally axisymmetric structures under arbitrary mechanical loads. This improved method breaks through the limitations of the previous basic rotation-superposition method in rotational similarity of load and structural axisymmetry, and greatly expands its application scope. In this paper, firstly, the basic theory of the rotation-superposition algorithm is introduced; secondly, the theoretical model of the generalized rotation-superposition method is established; thirdly, the effectiveness and accuracy are verified by using finite element simulations; finally, through a complex case study, the applicability of the generalized rotation-superposition method for complex engineering problems and its advantages in efficiently obtaining massive amounts of data are further illustrated. fields considerations physicsbased physics based rotationsuperposition rotation superposition loads axisymmetry scope paper firstly introduced secondly established thirdly simulations finally study illustrated

Abstract For solving a large amount of data processing and reducing the cost to improve detection accuracy, this paper proposes an intelligent detection model for railway vehicle wheels flat. We propose an automatic data processing algorithm for labeling large-scale data to maximize the benefits of each experiment data. To improve the generalization of the detection model to improve the accuracy, we combine the vehicle dynamics simulation data and the simulation experiment data based on the single wheel rolling test bench to construct the data set for detecting the wheel flat. Different from the existing detection models, this paper provides a method for constructing the data sets, which is used to assist machine learning in constructing the intelligent detection model. The data set and its construction method can also promote the application of data mining in the field of railway transportation. This paper verified the effectiveness of the features obtained from data processing in the detection model. The data set is used to detect and identify the wheel flat and the recognition accuracy is 98.6%. largescale scale models sets transportation 986 98 6 98.6% 9 98.6 98.

Abstract This paper introduces the Julia programming language as a dynamic, cost-effective, and efficient framework for implementing structural analysis packages. To achieve this, the finite element method was implemented for plane frames addressing the elastic instability problem through the Finite Element Method (FEM). Julia is a language open source, multiplatform, high-level and high-performance for technical and scientific computing, its compiler allows you to achieve speeds comparable to languages such as C and FORTRAN, but with more productive development dynamics due to its programming flexibility. Benchmarks between Julia and MATLAB are employed to discuss the processing costs, the programming techniques and paradigms used for computational performance. The results demonstrate that Julia performed the same analysis as the language used for comparison in 88.40% of the time, in addition to the fact that in loops comparisons case it reached 41.7% of the time for iteration, confirming its significant potential as a development tool of computational packages for structural analysis and scientific computing in general. dynamic costeffective, costeffective cost effective, effective cost-effective this FEM. FEM . (FEM) source multiplatform highlevel high level highperformance performance FORTRAN flexibility costs 8840 88 40 88.40 417 41 7 41.7 iteration general (FEM 884 8 4 88.4 41. 88.

Abstract A common issue with traditional warheads is the presence of a central blind zone when vertically striking targets. In this study, we proposed an axially reinforced warhead with different filler materials at the front end. Through experimental testing and simulations of single-point detonation at the bottom of the axially reinforced warhead, the fragmentation characteristics of the shell at the front end were analyzed, along with the fragment velocity and fragment distribution. The results showed that compared to traditional cylindrical warheads, the axially reinforced warhead filled with explosives or inert filler demonstrated significant improvements in fragmentation characteristics, the quality of the fragments, and the distribution of the fragments. Moreover, the fragment velocities showed greater similarity, and as the density of the inert filler increased, the improvement became more significant. In conclusion, the axially reinforced warhead with inert fillers at the front end produced evenly distributed fragments in the central damage area, which effectively improved the energy utilization of the warhead. targets study singlepoint single point analyzed Moreover similarity increased conclusion area

Abstract For the first time, this article uses higher-order IGA to study the high frequency of the functionally graded sandwich (FGS) square nanoplates with two different skin layers resting on elastic foundations. In this work, the elastic foundations use the Pasternak foundation (PF) model with a two-parameter as a spring stiffness ( k 1) and a shear layer stiffness ( k 2). The observation of small-scale effects in nanoplates is accomplished by incorporating nonlocal elasticity theory (NET) with a higher-order shear deformation theory (HSDT). The governing equation of nanoplates is derived from Hamilton's principle. An extensive parametric investigation has been conducted to illustrate the free vibration characteristics of FGS square nanoplates across both low and high frequency modes, placing a greater emphasis on the analysis of high frequency behaviour. Furthermore, the high eigenmodes and frequencies of the FGS circular/elliptical nanoplates are also added. Therefore, the findings presented here contribute to an improved understanding of the vibrations of FGS nanoplates at high frequencies. time higherorder higher order (FGS work PF (PF twoparameter parameter 1 2. 2 . 2) smallscale small scale NET (NET HSDT. HSDT (HSDT) Hamiltons Hamilton s principle modes behaviour Furthermore circularelliptical circular elliptical added Therefore (HSDT