Статті в журналах: "Thin-walled engineering structure"

1

Zhao, Xiao-Ling. "Thin-walled structure." Thin-Walled Structures 47, no. 10 (October 2009): 1019. http://dx.doi.org/10.1016/j.tws.2008.10.005.

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2

Zhou, Hui, Ping Xu, and Suchao Xie. "Composite energy-absorbing structures combining thin-walled metal and honeycomb structures." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 231, no. 4 (February 9, 2016): 394–405. http://dx.doi.org/10.1177/0954409716631579.

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The energy-absorbing structure of a crashworthy railway vehicle was designed by combining the characteristics of thin-walled metal structures and aluminum honeycomb structures: finite element models of collisions involving energy-absorbing structures were built in ANSYS/LS-DYNA. In these models, the thin-walled metal structure was modeled as a plastic kinematic hardening material, and the honeycomb structure was modeled as an equivalent solid model with orthotropic–anisotropic mechanical properties. The analysis showed that the safe velocity standard for rail vehicle collisions was improved from 25 km/h to 45 km/h by using a combined energy-absorbing structure; its energy absorption exceeded the sum of the energy absorbed by the thin-walled metal structure and honeycomb structure when loaded separately, because of the interaction effects of thin-walled metal structure and aluminum honeycomb structure. For an aluminum honeycomb to the same specification, the composite structure showed the highest SEA when using a thin-walled metal structure composed of bi-grooved tubes, followed by that using single-groove tubes: that with a straight-walled structure had the lowest SEA.

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3

Luo, Zhong, You Wang, Yunpeng Zhu, and Deyou Wang. "The Dynamic Similitude Design Method of Thin Walled Structures and Experimental Validation." Shock and Vibration 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/6836183.

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For the applicability of dynamic similitude models of thin walled structures, such as engine blades, turbine discs, and cylindrical shells, the dynamic similitude design of typical thin walled structures is investigated. The governing equation of typical thin walled structures is firstly unified, which guides to establishing dynamic scaling laws of typical thin walled structures. Based on the governing equation, geometrically complete scaling law of the typical thin walled structure is derived. In order to determine accurate distorted scaling laws of typical thin walled structures, three principles are proposed and theoretically proved by combining the sensitivity analysis and governing equation. Taking the thin walled annular plate as an example, geometrically complete and distorted scaling laws can be obtained based on the principles of determining dynamic scaling laws. Furthermore, the previous five orders’ accurate distorted scaling laws of thin walled annular plates are presented and numerically validated. Finally, the effectiveness of the similitude design method is validated by experimental annular plates.

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4

Shimoda, Masatoshi, and Yang Liu. "Free-Form Optimization of Thin-Walled Structure for Frequency Response Problem." Shock and Vibration 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/471646.

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We present a node-based free-form optimization method for designing forms of thin-walled structures in order to control vibration displacements or mode at a prescribed frequency. A squared displacement error norm is introduced at the prescribed surface as the objective functional to control the vibration displacements to target values in a frequency response problem. It is assumed that the thin-walled structure is varied in the normal direction to the surface and the thickness is constant. A nonparametric shape optimization problem is formulated, and the shape gradient function is theoretically derived using the material derivative method and the adjoint variable method. The shape gradient function obtained is applied to the surface of the thin-walled structure as a fictitious traction force to vary the form. With this free-form optimization method, an optimum thin-walled structure with a smooth free-form surface can be obtained without any shape parameterization. The calculated results show the effectiveness of the proposed method for the optimal free-form design of thin-walled structures with vibration mode control.

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5

Kneen, P. W. "Prestressed membrane structures — The ultimate thin-walled structure." Thin-Walled Structures 9, no. 1-4 (January 1990): 135–49. http://dx.doi.org/10.1016/0263-8231(90)90042-w.

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6

Ciubotariu, Vlad Andrei. "Crashing Behaviour Analysis of TWB Tubular Structures with Different Cross-Sections." Advanced Materials Research 814 (September 2013): 159–64. http://dx.doi.org/10.4028/www.scientific.net/amr.814.159.

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The present paper investigates the crashing behavior and energy absorption characteristics of thin-walled (tubular) structures with different cross-sections made from tailor welded blanks (TWB) which were subject of axial quasistatic loadings. Resulted data were obtained by using explicit nonlinear finite element code LS_Dyna V971. Implementing the TWB into the auto industry was an efficient method to decrease the general weight of different structures. By far, these kind of bimetallic structures are largely utilized in auto and naval industries because it led to important decrease of scarp quantities and general manufacturing costs, improved material use and probably the most important, great fuel efficiency. After reviewing the literature it was concluded that proper combination between mechanical characteristics of sheet metals, different thicknesses and cross-section shapes into the same thin-walled structure is far too little researched and understood. The aims of this study are better understandings of the crashing behavior regarding thin-walled structure with various cross-sections made from TWB blanks subject to quasistatic loadings. The non-linear finite element platform LS_Dyna V971 was used for the numerical analysis of the crushing behavior regarding the thin-walled structures. Having two materials constituting the thin-walled structures, the crashing behavior changed during the quasistatic loading. Thus, the crashing inertia of the structure is somehow limited and controlled. It is noted that material ratio should not be randomly chosen due to the unexpected crashing mode which could aggravate the prediction and control of the crashing behavior of the thin-walled structure.

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7

Kreja, Ireneusz, Tomasz Mikulski, and Czeslaw Szymczak. "ADJOINT APPROACH SENSITIVITY ANALYSIS OF THIN‐WALLED BEAMS AND FRAMES." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 11, no. 1 (March 31, 2005): 57–64. http://dx.doi.org/10.3846/13923730.2005.9636333.

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Sensitivity analysis of beams and frames assembled of thin‐walled members is presented within the adjoint approach. Static loads and structures composed of thin‐walled members with the bisymmetrical open cross‐section are considered. The analysed structure is represented by the one‐dimensional model consisting of thin‐walled beam elements based on the classical assumptions of the theory of thin‐walled beams of non‐deformable cross‐section together with superelements applied in place of location of structure nodes, restraints and stiffeners. The results of sensitivity analysis, obtained for the structure model described above, are compared with the results of the detailed FEM model, where the whole structure is discretised with the use of QUAD4 shell elements of the system MSC/NASTRAN.

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8

Yang, Li Feng, Yang Shi, and Wei Na Liu. "The Study of Thin-Walled Complex Parts Reverse Engineering Key Technologies." Advanced Materials Research 500 (April 2012): 511–16. http://dx.doi.org/10.4028/www.scientific.net/amr.500.511.

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The thin-walled complex parts reverse engineering is very different from conventional parts or the parts have some simple surface reverse engineering. There are some features. For example, it may have a lot of surface, structure complex, and it is difficulty that scanning point cloud data. Through this thesis, we put a stent by pedal as a thin-walled complex part, introduced some technology about it reverse engineering.

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9

Li, Zhichao, Subhash Rakheja, and Wen-Bin Shangguan. "Crushing behavior and crashworthiness optimization of multi-cell square tubes under multiple loading angles." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 234, no. 5 (August 21, 2019): 1497–511. http://dx.doi.org/10.1177/0954407019869127.

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Thin-walled structures are widely used as energy absorbers in automotive vehicles due to their lightweight and high-energy absorption efficiency. In order to improve the energy absorption characteristics of thin-walled structures subjected to different loading angles, different types of novel multi-cell structures are proposed in this paper. The numerical method is used to study the crushing behaviors of the proposed multi-cell structures under different loading angles. It is found that the proposed multi-cell structures have considerably small initial peak force under axial load and avoid the appearance of global buckling deformation mode under oblique loads. Moreover, reasonably distributed wall thickness for each square tube in the thin-walled structure can enhance its energy absorption capacity under different loading angles.

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10

Marur, P. R. "Analysis of thin-walled frames considering joint flexibilities." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 221, no. 10 (October 1, 2007): 1221–29. http://dx.doi.org/10.1243/09544070jauto575.

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TAnalytical models are developed for static and dynamic analysis of thin-walled frames representing the automotive side structures. The model is based on one-dimensional beam theory that considers joint flexibility to compute stiffness and frequency response of the whole frame structure. The computed out-of-plane displacements under static and impact loading are in good agreement with those obtained from the shell finite element method. Using the validated analytical model, the influence of joint flexibility on the elastic response of the side structure is studied.

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11

Chen, De Zhi, and Shun Xiang Xu. "Research and Engineering Application of Wall-Outside Blasting Charge in Blasting Demolition of Underground Thin-Walled Structure." Advanced Materials Research 739 (August 2013): 314–17. http://dx.doi.org/10.4028/www.scientific.net/amr.739.314.

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When the blasting method is used to demolish the underground thin-walled structure, the safety misadventure occurs possibly due to the small burden, the heavy workload of the drilling and excavation as well as the long construction time, thus, its demolition is more difficult than that of the foundation. This paper describes the new underground thin-walled structure blasting demolition method - the wall-outside blasting charge method and the primary discussion about the blasting mechanism of the wall-outside blasting charge method, which is used in engineering practice. The demolition practice has proved that the wall-outside blasting charge method is a safe, simple and efficient and economic method to demolish the thin-walled structure such as underground sinking well and the pool, its blasting fragmentation is uniform, the fly-rock is easily controlled, and this method has the good economic benefit and the application prospect.

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12

Meng, Zhuo, Qin Sun, and Jin Feng Jiang. "Parameter Inversion of Thin-Walled Structure Using Numerical Optimization Approach." Advanced Materials Research 308-310 (August 2011): 1614–18. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.1614.

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Based on the theory of structure impact dynamic and numerical optimization, application of SQP algorithm in nonlinear parameter inversion is demonstrated in this paper by combining the optimization software and finite element software. Parameter inversion of thin-walled cylinder subjected to axial impact load is studied. The material parameters of thin-walled cylinder are obtained from inversion; besides, the whole process of numerical optimization parameter inversed method is demonstrated.

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13

Wang, Qing Chun, Hao Long Niu, Guo Quan Wang, and Yu Xin Wang. "Numerical Simulation on Bending Characteristics of Aluminium Foam Filled Thin-Walled Tubes." Advanced Materials Research 213 (February 2011): 88–92. http://dx.doi.org/10.4028/www.scientific.net/amr.213.88.

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Different aluminum foam filling lengths were used to increase the bending energy absorbing capacity of the popularly used hat sections. Bending energy-absorption performance of the thin-walled tubes was numerically studied by explicit non-linear software LS-Dyna. First empty hat section subjected to quasi-static bending crushing was simulated, then structures with different aluminium foam filling lengths were calculated, finally energy absorption capacity of these structures were compared. Calculation results showed that, the internal energy absorbed and mass specific energy absorption capacity of foam filled thin walled structures were increased significantly compared to the empty sections. The reason of the improvement was mainly due to the contact of the aluminium foam and the structure. Aluminium foam filling is a promising method for improving lateral energy absorbing capacity of thin-walled sections.

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14

Rosmanit, Miroslav, Přemysl Pařenica, Oldřich Sucharda, and Petr Lehner. "Physical Tests of Alternative Connections of Different High Roof Purlins Regarding Upward Loading." Buildings 11, no. 11 (October 29, 2021): 512. http://dx.doi.org/10.3390/buildings11110512.

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Thin-walled cold-rolled sections are used in the construction industry, especially in the roofing of large-span halls. The load-bearing capacity of a thin-walled structure depends to a large extent on the load-bearing capacity of the details at the point of attachment to the structure and the interconnection of the individual thin-walled elements. Therefore, in the case of thin-walled structures, it is necessary to use additional structural elements such as local reinforcement, stabilising elements, supports, and other structural measures such as the doubling of profiles. This paper focused on the behaviour of tall Z300 and Z350 mm thin-walled trusses at the connection to the superstructure regarding upward loading (e.g., wind suction and so on). Two section thicknesses, 1.89 mm and 2.85 mm, were experimentally analysed. Furthermore, two types of connections were prepared, more precisely without and with a reinforced buckle. The experiments aimed to investigate the behaviour and load-carrying capacity of the detail of the roof truss connections to the supporting structure. The resulting load capacity values were compared with normative approaches. Analyses of the details of the bolt in the connection are also presented. The paper presents a practical evaluation of the physical test on real structural members.

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15

Yuan, Bao Long, Zi Dong Wang, Xiang Ming Li, and Chun Jing Wu. "Preparation and Properties of Thin Walled Copper Tube by a Short Process Method." Advanced Materials Research 148-149 (October 2010): 732–35. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.732.

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Thin walled copper tube is prepared in vacuum melting and argon protecting continuous unidirectional solidification equipment by a short process method. The size of the thin walled copper tube is ф39×1.8 mm. The effect of process parameters on the solidification structure and the surface quality of the thin walled copper tube is investigated. The mechanical properties and electrical properties are tested and analyzed. The results show that the thin walled tube with columnar crystal structure and good quality surface can be obtained continuously and stably under the most appropriate process of the melting temperature is between 1423K and 1453K, the cooling water volume is 0.2～0.5m3•h-1, the cooling distance is 50mm, the drawing speed is not higher 20m•h-1. The elongation can reach 60%, and conductivity can reach 102.6%IACS.

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16

Zalipaev, V. V., I. S. Jones, and A. B. Movchan. "A thermoelastic junction problem in a thin-walled structure: asymptotic analysis." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 465, no. 2104 (January 20, 2009): 1309–21. http://dx.doi.org/10.1098/rspa.2008.0451.

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The two-dimensional model for a thin-walled structure in the plane strain time-harmonic case is discussed. A model of a surface crack defect subjected to oscillatory thermal loading in the middle part of the thin-walled bridges is presented. As a first part of the asymptotic model, the effective transmission condition in the vicinity of a deep surface-breaking crack in a thin-walled bridge is discussed. Then, the two-term boundary layer model determining the asymptotic behaviour of the field near the tip of the crack is constructed.

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17

Pan, Futing, Ying Wang, and Chunxiao Huang. "Design and bearing capacity analysis of cold-formed thin-walled steel-timber composite members." E3S Web of Conferences 248 (2021): 03047. http://dx.doi.org/10.1051/e3sconf/202124803047.

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Cold-formed thin-walled steel has light weight, large width thickness ratio, good economy and seismic performance. It is easy to realize standardization of design, and is very suitable for the development of prefabricated buildings. Due to the large width thickness ratio of cold-formed thin-walled steel , the steel plate is prone to local buckling when it is compressed, which will reduce the ductility and bearing capacity of the structure, which also leads to the limitation of the use of cold-formed thin-walled steel structure system in medium and high-rise buildings. In this paper, a kind of cold-formed thin-walled steel-timber composite members is designed. The section steel and the board are closely linked by bolts to work together. The thickness of the board and the spacing of the bolts are designed respectively, so as to provide reference for engineering design.

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18

Xu, Fengxiang, Suo Zhang, and Kunying Wu. "Dynamic crashing behavior of thin-walled conical tubular structures with nonlinearly-graded diameters." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 7 (June 22, 2018): 2456–66. http://dx.doi.org/10.1177/0954406218784609.

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Thin-walled structures with graded property have been paid more attention in recent years due to their significant balance between lightweight and crashworthiness. However, few studies have been focused on energy absorption capacity of thin-walled conical tubes with graded diameters. In this paper, the thin-walled conical aluminum tubes with nonlinearly-graded diameters are introduced and their corresponding crashing characteristics are performed. The diameters are assumed to nonlinearly vary according to a power-law distribution function primarily determined by a graded exponent n. It is found that the total weight of thin-walled conical tubes decreases with the increasing of the gradient exponent. The energy-absorbed performances such as specific energy absorption, initial peak crashing force, and mean crashing force of those graded tubular structures are numerically analyzed. And then the effects of various geometric parameters such as the gradient exponent, deformation distance, and diameter range on crashing behaviors are further evaluated. It is observed that those parameters especially the gradient exponent has significantly obvious effects on crashworthiness of the proposed nonlinearly graded tubes. It is also noted that the straight conical structure with gradient n = 1.0 may not show the best energy absorption characteristics compared with other gradients. The work could provide valuable information for effective design of thin-walled energy-absorbing structures with variable geometrical parameters.

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19

Kreja, Ireneusz, Tomasz Mikulski, and Czeslaw Szymczak. "APPLICATION OF SUPERELEMENTS IN STATIC ANALYSIS OF THIN‐WALLED STRUCTURES." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 10, no. 2 (June 30, 2004): 113–22. http://dx.doi.org/10.3846/13923730.2004.9636295.

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A concept of a beam superelement is suggested as a new tool in the static analysis of structures made of thin‐walled members. This proposal seems to be especially attractive for treating the problems where the existing one‐dimensional models do not provide proper solutions. This class of problems includes, for instance, the torsion of thin‐walled beams with battens and the determination of the bimoment distribution at the nodes of frames made of thin‐walled members. The entire segment of the thin‐walled beam with warping stiffener or the whole node of the frame is modelled with shell elements. The stiffness matrix of such thin‐walled beam superelement can be estimated according to the standard procedure of the enforced unit displacements. The accuracy of the proposed one‐dimensional model has proved to be comparable to that offered by the detailed FEM model where the whole structure is represented by a very large number of shell elements.

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20

Wang, Qianni, Caifu Qian, and Zhiwei Wu. "Research on the Rational Design Method of Strength Reinforcement for Thin-Walled Structure Based on Limit Load Analysis." Applied Sciences 12, no. 4 (February 20, 2022): 2208. http://dx.doi.org/10.3390/app12042208.

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Thin-walled structures subjected to internal or external pressure usually need to be reinforced with ribs. The design of ribs is generally based on experiences in engineering, and the results are often very conservative. In this paper, an approach for the rational design of reinforced ribs on thin-walled structures is proposed based on the limit load analysis method, maximizing the limit load of the reinforced thin-walled structure or minimizing the weight of the reinforced ribs. Firstly, the limit load numerical analysis was conducted to study rib forms at the continuous and discontinuous regions of the structure and find the rational ribs which provide the most effective reinforcement for the structure. Then, using the proposed rib forms, an engine test cabin was re-designed based on the limit load analysis to verify the feasibility and effects of the rib design. The engine test cabin after the redesign of the rib plate can reach 98% of the limit load of the original test cabin while the weight of reinforcing ribs is only 62% of the weight of the original ones, which means that the reinforcement design approach based on the limit load analysis method and the rib forms proposed in this paper is effective and feasible, and can achieve a structural lightweight design.

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21

Wang, Chun, Xuan Ming Zhang, and Chun Ying Tang. "Manufacturing Process of Large Scale Sandwich Structure with Variable Thickness of PMI Foam Core." Advanced Materials Research 299-300 (July 2011): 816–19. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.816.

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Composite sandwich structures are extensively used in the aerospace, wind power, sports equipment, shipbuilding, automotive and train locomotive industries in order to improve structure rigidity and reduce weight. The molding process of sandwich structure using glass cloth and fibre materials as panels has been reported in many literatures. However, few researches are found relative to the molding process of large scale sandwich structure with the characteristics of thin-walled aluminum alloy panels and variable thickness of Polymethacrylimide (PMI) foam cores. This paper describes a preformed molding process that consists of thermoforming foam core blocks, assembling blocks into a whole sandwich core, CNC machining the sandwich core according to surface models of the thin-walled aluminum alloy panels, and finally, bonding and curing panels and sandwich cores.

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22

Chen, Bing Zhi, Zhi Dong Lv, Su Ming Xie, and Wen Zhong Zhao. "Anti-Crashing Energy-Absorbing Simulation and Optimization of Thin-Walled Components." Advanced Materials Research 201-203 (February 2011): 347–55. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.347.

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Higher speed and loading capacity of trains nowadays have aroused higher ability of crashworthiness, which could be effectively improved by well-designed energy absorbing structures. The thin-walled components, the most traditional and effective energy absorbing device, have been widely used for design of energy absorbing device. As a result, the thin-walled components are used as an example to examine the process of axial compression of it. A comparison of a dynamic compressing simulation on fold-collapse tube and the experimental result of it is made, which shows the two matches very well. Based on this comparison, a further research and optimization on the thin-walled energy absorbing components is implemented. With the material modal and finite element modal of this component, a research on the simulation of PAM-CRASH, the crashing finite element Software, is implemented on such component with different shapes of cross-section, different thickness and square cross-sections with single-cell and multi-cell. What's more, suggestions on such thin-walled components energy absorbing structure is given based on the analysis of the parameters of the simulation.

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Yu, Wei, Hui Jian Li, Xi Liang, and Chang Jun He. "Studies on Mechanical Properties of Thin-Walled MHS Structure." Advanced Materials Research 189-193 (February 2011): 1321–24. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.1321.

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Metallic hollow sphere structure cellular material is a type of super-light cellular metallic material. Its basic cell is thin-walled metallic hollow sphere. A series of quasi-static uniaxial compression experiments of two spheres array, three spheres array and tetrahedral packing structure were conducted. It is found that one sphere produces deformation at the contact place of two spheres, and the deformation is larger than that at the contact place of plates. The three spheres array and tetrahedral packing structure have the same phenomenon. Then, the Young’s moduli of these three models had been studied, and it is found that the tetrahedral packing structure has a larger value than the others. The compressive deformation behaviors of two and three spheres with the spheres glued together were studied too. These research findings can be the basis of the design of MHS structure cellular material.

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Fei, Jixiong, Bin Lin, Shuai Yan, Mei Ding, Jin Zhang, Chunhui Ji, and Xiaofeng Zhang. "Modeling of surface roughness for manufactured thin-walled structure." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 233, no. 4 (June 18, 2018): 1216–23. http://dx.doi.org/10.1177/0954405418780165.

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Deformation of thin-walled structure during machining will influence the surface quality of the final part. Present article investigates this problem and develops a method to predict the surface roughness of the machined surface. To achieve this, the prerequisite is to obtain the dynamic deformation along the milling path. To calculate it accurately, the workpiece is simplified as thin-walled shell and the milling force is simplified as moving input. An expression of the dynamic deformation of the whole structure, which under the excitation of moving milling force, is derived by solving the vibration equation using modal superposition method. Then, the deformation along the milling path is computed by substituting the path coordinates into the expression. The deformation along the milling path is filtered to remove its low-frequency and mid-frequency signals before it is used to evaluate the surface roughness of the machined surface. At last, several machining cases are implemented to demonstrate the proposed method. The experimental results match well with the predicted results. From the predicted and experimental results, it is founded that the deformation during processing is the main reason leading to the poor surface quality of the flexible machined workpiece.

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25

Kruntcheva, Mariana R. "Acoustic-Structural Resonances of Thin-Walled Structure—Gas Systems." Journal of Vibration and Acoustics 128, no. 6 (May 10, 2006): 722–31. http://dx.doi.org/10.1115/1.2345679.

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This paper summarizes a theoretical study, which is a natural continuation of approximately 50 years of research in the field of acoustoelasticity. Recently, the researchers’ interest has been directed towards considering compressible fluid in contact with thin walled structures as it was found that the acoustic-structural coupling significantly changes the dynamic behavior of the system. Despite the interesting findings the main results still need additional, numerical, or experimental verification. The present work is intended to cast more light on the acoustic-structure coupling of light fluid-shell systems using a numerical approach, namely 3-D finite element (FE) modeling. Two different acoustoelastic systems are considered. The first system is a thin circular cylindrical shell containing light fluid in a coaxial annular duct and the second system is a thin-walled vehicle passenger compartment interacting with the enclosed cavity. Both systems are studied using ANSYS finite element code. The modeling involved shell finite elements for the structure and 3-D acoustic elements for the cavity. The 3-D FE modal analysis used produced results visualizing the complex picture of acoustic-structure coupling. It was confirmed that (1) in both fluid-elastic systems the strongest acoustic-structural coupling exists if the resonances of uncoupled acoustic and mechanical systems are close and (2) the nature of the acoustic-structural coupling is identical in the two cases studied. However, it was found that strong coupling between the thin-walled structure and the acoustic cavity exists in the vicinity of any uncoupled acoustic resonance. Thus, the coupled properties of the systems were found to be dominated by the uncoupled acoustic resonances. As the focus of this study is on the mode shapes of vibration, it was found that coupled acoustic-structure modes of vibration exist in the neighborhood of an uncoupled acoustic resonance, which means that the coupled system manifests a specific type of energy exchange. These modes were termed coupled “combined” modes to differentiate from the coupled component responses. It was also found that the coupled “combined” modes are clustered around a rigid-walled cavity mode, and any acoustic-structure resonance of a given group involves this particular uncoupled acoustic mode. In conclusion, it is shown that the acoustic-structure interaction causes the appearance of coupled “combined” modes not existing in the shell in vacuo or rigid-walled acoustic spectrum. It was found also that the subsystems preserve their capability of independent vibration responses, i.e., the response at the component modes is believed to be strong at their uncoupled frequencies.

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26

Wang, Chun, Xuan Ming Zhang, and Xiao Wang. "Scanning and Modeling of Large Thin-Walled Curved Surface Part." Advanced Materials Research 299-300 (July 2011): 810–15. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.810.

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The large sandwich structure composed of thin-walled aluminum alloy panels, and variable thickness of honeycomb or Polymethacrylimide (PMI) foam core is usually manufactured by pre-bonded forming process, that is pre-forming panels and sandwich core, and then curing adhesive them to be sandwich structure. Welding process of large thin-walled panel causes the panel surface to be irregular and have greater errors relative to the design surface. Simply CNC machining the sandwich core according to the design surface cannot guarantee an exact match sandwich core consistent with the panels. The actual topography of the panels must be scanned. It is proposed that the use of a new hand-held laser scanner, Handyscan to scan large thin-walled curved surface parts, of Geomagic software to handle the acquired point clouds and construct the surface model.

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Flodr, Jakub, Martin Krejsa, David Mikolášek, Oldrich Sucharda, and Libor Žídek. "Mathematical Modelling of Thin-Walled Cold-Rolled Cross-Section." Applied Mechanics and Materials 617 (August 2014): 171–74. http://dx.doi.org/10.4028/www.scientific.net/amm.617.171.

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The purpose of the paper is to perform a static analysis of a thin-wall cold-rolled steel cross-section of a trapezoidal sheet by means of a mathematical model developed in ANSYS, commercially available software applications. The trapezoidal sheets are used typically as an external cladding which covers the structures of steel halls. Investigating into behaviour of the trapezoidal sheets subjected to extreme loads represents an urgent issue in wind engineering. A physical tension test has been performed in order to verify and confirm the mathematical model. Experiments have been performed to prove results of the static analysis into the behaviour of a load-carrying structure formed by a thin-wall cross-section.

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Imene, Mahi, Djafour Naoual, and Djafour Mustapha. "Study of Local and Distortional Stability of Thin-Walled Structures." MATEC Web of Conferences 149 (2018): 01089. http://dx.doi.org/10.1051/matecconf/201814901089.

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Thin-walled structures have an increasingly large and growing field of application in the engineering sector, the goal behind using this type of structure is efficiency in terms of resistance and cost, however the stability of its components (the thin walls) remains the first aspect of the behavior, and a primordial factor in the design process. The hot rolled sections are known by a consequent post-buckling reserve, cold-formed steel sections which are thin-walled elements also benefit, in this case, it seems essential to take into account the favorable effects of this reserve in to the verification procedure of the resistance with respect to the three modes of failures of this type of structure. The design method that takes into account this reserve of resistance is inevitably the effective width method. The direct strength method has been developed to improve the speed and efficiency of the design of thin-walled profiles. The latter mainly uses the buckling loads (for Local, Distortional and Global mode) obtained from a numerical analysis and the resistance curves calibrated experimentally to predict the ultimate load of the profile. Among those, the behavior of a set of Cshaped profiles (highly industrialized) is studied, this type of section is assumed to be very prone to modes of local and distortional instability. The outcome of this investigation revealed very relevant conclusions both scientifically and practically.

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29

Meshreki, Mouhab, Helmi Attia, and József Kövecses. "Modeling the Varying Dynamics of Thin-Walled Aerospace Structures for Fixture Design Using Genetic Algorithms." Advanced Materials Research 223 (April 2011): 652–61. http://dx.doi.org/10.4028/www.scientific.net/amr.223.652.

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Fixture design for milling of aerospace thin-walled structures is a challenging process due to the high ﬂexibility of the structure and the nonlinear interaction between the forces and the system dynamics. At the same time, the industry is aiming at achieving tight tolerances while maintaining a high level of productivity. Numerical models based on FEM have been developed to simulate the dynamics of thin-walled structures and the effect of the ﬁxture layout. These models require an extensive computational effort, which makes their use for optimization very unpractical. In this research work, a new concept is introduced by using a multi-span plate with torsional and translational springs to simulate the varying dynamics of thin-walled structure during machining. A formulation, based on holonomic constraints, was developed and implemented to take into account the effect of rigid ﬁxture supports. The developed model, which reduces the computational time by one to two orders of magnitude as compared to FE models, is used to predict the dynamic response of complex aerospace structural elements including pockets and ribs while taking into account different ﬁxture layouts. The model predictions are validated numerically. The developed model meets the conﬂicting requirements of prediction accuracy and computational efﬁciency.

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30

Xing, D., W. Chen, J. Ma, and L. Zhao. "Structural bionic design for thin-walled cylindrical shell against buckling under axial compression." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 225, no. 11 (August 4, 2011): 2619–27. http://dx.doi.org/10.1177/0954406211407820.

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In nature, bamboo develops an excellent structure to bear nature forces, and it is very helpful for designing thin-walled cylindrical shells with high load-bearing efficiency. In this article, the cross-section of bamboo is investigated, and the feature of the gradual distribution of vascular bundles in bamboo cross-section is outlined. Based on that, a structural bionic design for thin-walled cylindrical shells is presented, of which the manufacturability is also taken into consideration. The comparison between the bionic thin-walled cylindrical shell and a simple hollow one with the same weight showed that the load-bearing efficiency was improved by 44.7 per cent.

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31

Ghareb, AL-Hasnawi Yasser Sami, Andrey V. Shevchenko, and Omar Ismael Alhashimi. "Light Steel Thin -Walled Structures Composite Beam of Cellular Concrete." Materials Science Forum 974 (December 2019): 596–600. http://dx.doi.org/10.4028/www.scientific.net/msf.974.596.

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The cost-efficient field design is very important in the civil engineering. Therefore, the cold-formed steel structures (CFS) are preferred for construction. A Sophisticated CFS structure which uses a Cellular Concrete is implemented in this paper. The utilization Cold-Formed Steel (CFS) structures have become increasingly popular in different fields of building technology. The reasons behind the growing popularity of these products include their fabrication ease, high strength/weight ratio and suitability for a wide range of applications. These advantages can result in more economic designs, as compared with hot-rolled steel, especially in short-span applications. In this project work an attempt to use a Cold formed steel section as replacement to conventional steel reinforcement bar has been made.

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32

Zhi, Zhi, ShiYong Guo, LuWei Chen, and Yan Zhu. "Research on damage mechanism and protection of the collision penetration of the thin-walled long rod structure." Science Progress 103, no. 1 (September 16, 2019): 003685041987421. http://dx.doi.org/10.1177/0036850419874216.

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Traffic accidents have been closely concerned by the society, and the serious traffic accidents caused by vehicle and guardrail collisions are one of the main manifestations. However, the research in the field of vehicle and guardrail collisions is mainly limited to the waveform guardrail on the expressway, and there is little research on the urban road guardrail, especially in the secondary damage caused by guardrails field. Moreover, the collision between vehicle and the rectangular guardrail of city road is easy to form thin-walled long rod, and it penetrates the driver’s chest. To evaluate and analyze the injury results and mechanism of this phenomenon, a penetrating finite element model of chest bone characterized by Chinese human is established using the medical software (MIMICS) and engineering software (HYPERMESH). The model validation is mainly dependent on the corpse impact test. In addition, the software (LS-DYNA) is deployed to simulate the thin-walled long rod penetration. According to the analysis of the “PENETRATION,” it is found that the cavity effect produced by the thin-walled long rod through the chest, and the degree of chest damage is related to the speed, angle, weight, and stability of the thin-walled long rod. The difference between the peak value of collision corpse experiment and simulation peak value is less than 5%, which implies that the model is reasonable. Besides, the simulation results also confirm the accident and medical diagnosis cases. As a common form of secondary injury in traffic accidents and a typical case of medical penetrating injury, the thin-walled long rod penetrating injury has important reference value for studies in both directions.

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33

Li, Yifeng, Xunpeng Qin, Qiang Wu, Zeqi Hu, and Tan Shao. "Fabrication of curved overhanging thin-walled structure with robotic wire and arc additive manufacturing (RWAAM)." Industrial Robot: the international journal of robotics research and application 47, no. 1 (August 19, 2019): 102–10. http://dx.doi.org/10.1108/ir-05-2019-0112.

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Purpose Robotic wire and arc additive manufacturing (RWAAM) is becoming more and more popular for its capability of fabricating metallic parts with complicated structure. To unlock the potential of 6-DOF industrial robots and improve the power of additive manufacturing, this paper aims to present a method to fabricate curved overhanging thin-walled parts free from turn table and support structures. Design/methodology/approach Five groups of straight inclined thin-walled parts with different angles were fabricated with the torch aligned with the inclination angle using RWAAM, and the angle precision was verified by recording the growth of each layer in both horizontal and vertical directions; furthermore, the experimental phenomena was explained with the force model of the molten pool and the forming characteristics was investigated. Based on the results above, an algorithm for fabricating curved overhanging thin-walled part was presented and validated. Findings The force model and forming characteristics during the RWAAM process were investigated. Based on the result, the influence of the torch orientation on the weld pool flow was used to control the pool flow, then a practical algorithm for fabricating curved overhanging thin-walled part was proposed and validated. Originality/value Regarding the fabrication of curved overhanging thin-walled parts, given the influences of the torch angles on the deposited morphology, porosity formation rate and weld pool flow, the flexibility of 6-DOF industrial robot was fully used to realize instant adjustment of the torch angle. In this paper, the deposition point and torch orientation of each layer of a robotic fabrication path was determined by the contour equation of the curve surface. By adjusting the torch angle, the pool flow was controlled and better forming quality was acquired.

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34

Ahmed, Naveed, Muhammad Ahmad Naeem, Ateekh Ur Rehman, Madiha Rafaqat, Usama Umer, and Adham E. Ragab. "High Aspect Ratio Thin-Walled Structures in D2 Steel through Wire Electric Discharge Machining (EDM)." Micromachines 12, no. 1 (December 22, 2020): 1. http://dx.doi.org/10.3390/mi12010001.

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Thin structures are often required for several engineering applications. Although thick sections are relatively easy to produce, the cutting of thin sections poses greater challenges, particularly in the case of thermal machining processes. The level of difficulty is increased if the thin sections are of larger lengths and heights. In this study, high-aspect-ratio thin structures of micrometer thickness (117–500 µm) were fabricated from D2 steel through wire electrical discharge machining. Machining conditions were kept constant, whereas the structure (fins) sizes were varied in terms of fin thickness (FT), fin height (FH), and fin length (FL). The effects of variation in FT, FH, and FL were assessed over the machining errors (FT and FL errors) and structure formation and its quality. Experiments were conducted in a phased manner (four phases) to determine the minimum possible FT and maximum possible FL that could be achieved without compromising the shape of the structure (straight and uniform cross-section). Thin structures of smaller lengths (1–2 mm long) can be fabricated easily, but, as the length exceeds 2 mm, the structure formation loses its shape integrity and the structure becomes broken, deflected, or deflected and merged at the apex point of the fins.

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35

Wang, Tong Yue, Ning He, and Liang Li. "Study on the Stability of High-Speed Milling of Thin-Walled Workpiece." Advanced Materials Research 97-101 (March 2010): 1849–52. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.1849.

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Thin-walled structure is easy to vibrate in machining. The dynamic milling model of thin-walled workpiece is analyzed based on the analysis of degrees in two perpendicular directions of machine tool-workpiece system. In high speed milling of 2A12 aluminum alloy, the compensation method based on the modification of inertia effect is proposed and accurate cutting force coefficients are obtained. The machining system is divided into “spindle-cutter” and “workpiece-fixture” two sub-systems and the modal parameters of two sub-systems are acquired via modal analysis experiments. Finally, the stability lobes for high speed milling of 2A12 thin-walled workpiece are obtained by the use of these parameters. The results are verified against cutting tests.

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36

Zalipaev, V. V., A. B. Movchan, and I. S. Jones. "Waves in lattices with imperfect junctions and localized defect modes." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 464, no. 2096 (April 9, 2008): 2037–54. http://dx.doi.org/10.1098/rspa.2007.0255.

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A correspondence between continuum periodic structures and discrete lattices is well known in the theory of elasticity. Frequently, lattice models are the result of the discretization of continuous mechanical problems. In this paper, we discuss the discretization of two-dimensional square thin-walled structures. We consider the case when thin-walled bridges have defects in the vicinity of junctions. At these points, the displacement satisfies an effective Robin-type boundary condition. We study a defect vibration mode localized in the neighbourhood of the damaged junction. We analyse dispersion diagrams that show the existence of standing waves in a structure with periodically distributed defects.

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37

Prabowo, Aditya Rio, Tuswan Tuswan, Dandun Mahesa Prabowoputra, and Ridwan Ridwan. "Deformation of designed steel plates: An optimisation of the side hull structure using the finite element approach." Open Engineering 11, no. 1 (January 1, 2021): 1034–47. http://dx.doi.org/10.1515/eng-2021-0104.

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Abstract Thin-walled structures, which generally consist of unstiffened and stiffened plates, are widely used in engineering as one of the core features of any product or construction. Due to environmental conditions and working operation, the components of the structure unavoidably become subject to various types of loading. Deformation patterns and overall behaviour are expected to be varied, as different materials are considered in the structures. In this situation, assessments are required to quantify the responses and determine the relationships between the structural behaviour and structural parameters. In this work, we attempt to obtain the behaviour data of unstiffened and stiffened plates as components of thin-walled structures. The material class – i.e. low- and medium-carbon steels – and loading parameters (i.e. type and angle) are taken as the main inputs in the finite element analysis. A geometrical design is adopted based on the side hull structure of a medium-sized tanker, for which two plate types, unstiffened and stiffened, are used. The results indicate that increasing the loading angle reduces the force experienced by the plate, while the greater the loading direction angle is, the greater the total displacement value will be. In terms of the plate design, the stiffener is observed to reduce the force expansion during the loading of the stiffened plate.

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38

ZHAO, Xilu, Yabo HU, and Ichiro HAGIWARA. "Optimal Design for Crash Characteristics of Cylindrical Thin-Walled Structure Using Origami Engineering." TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A 76, no. 761 (2010): 10–17. http://dx.doi.org/10.1299/kikaia.76.10.

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39

Chew, G. G., I. C. Howard, and E. A. Patterson. "On the presence of bending stresses in inflated thin-walled structures." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 211, no. 5 (May 1, 1997): 341–48. http://dx.doi.org/10.1243/0954406971522097.

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It is proposed that, in appropriate circumstances, membrane structures can experience bending moments. On uniformly inflating a thin sheet structure, which has a shape consisting of multiple curvatures, the structure will deform in such a way that the final shape will have a single radius of curvature, assuming that failure does not occur. It is the large change of shape from a multicurvature surface to a single curvature surface that causes bending moments to exist within a membrane. The validity of the hypothesis has been demonstrated using four finite element models, including an elliptical cylinder, an ellipsoid, a ‘double’ cone and a trileaflet heart valve.

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40

Karamoozian, Aminreza, Chin An Tan, and Liangmo Wang. "Squeal analysis of thin-walled lattice brake disc structure." Materials & Design 149 (July 2018): 1–14. http://dx.doi.org/10.1016/j.matdes.2018.03.044.

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41

Wang, Shijun, Zan Wang, Chang Ping, Xing Wang, Huiying Wu, Jian Feng, and Jianguo Cai. "Structural Performance of Thin-Walled Twisted Box-Section Structure." Buildings 12, no. 1 (December 26, 2021): 12. http://dx.doi.org/10.3390/buildings12010012.

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The light weight and high strength-to-mass ratio of thin-walled boxed sections have incited interest in their widespread use in the construction of domes. However, the installation of these sections in forming the dome geometry has induced initial twists and curving features, to which their mechanical response has rarely been explored. Therefore, the structural performance of a structure with thin-walled twisted box sections is numerically studied in this paper, employing ANSYS, the verification of which is carried out through a comparison with experimental results. Additional components examined include the longitudinal stiffening rib, diaphragm, and web. The effects of variations in the thicknesses of these member plates on the mechanical behaviors are investigated. In general, the ultimate capacity of the structure is improved by increasing the thickness of the longitudinal stiffening rib, diaphragm, and web, but the strengthening effect of the stiffener is limited by a certain thickness enhancement. The common failure mode of the initial model is found to be an overall elastic-plastic buckling. A reduction in the thickness of the stiffener or web creates a curving deformation zone in the lower arch at the ultimate capacity, whereas the diaphragm thickness has little effect on the failure mode of the model.

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42

Šapalas, Antanas, Gintas Šaučiuvėnas, Konstantin Rasiulis, Mečislovas Griškevičius, and Tomas Gečys. "BEHAVIOUR OF VERTICAL CYLINDRICAL TANK WITH LOCAL WALL IMPERFECTIONS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 25, no. 3 (March 29, 2019): 287–96. http://dx.doi.org/10.3846/jcem.2019.9629.

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Design of modern thin-walled metal structures is widely used around the world. In recent decades, more comprehensive research is carried out to investigate the behaviour of various thin-walled structures. Generally, the structure with regular geometry is investigated. In various countries such as USA, Russia, and the European Union issued the standards on regulation of the construction, design and maintenance of thin-walled structures. The actually used period of tanks usually is longer than recommendatory period. Recommendatory maintenance period of metal tanks is 15–20 years. Therefore, for such structures one of the most considerable questions is the residual load bearing capacity beyond the end of the maintenance period. This phase of using of structures is associated with complex investigation and numerical analysis of thin-walled structures. In this paper the load bearing capacity of the steel wall of the existing over-ground vertical cylindrical tank in volume of 5,000 m3 with a single defect and with a few contiguous local defects of the shape is analyzed. Calculations carried out are taking into account all the imperfections of the wall geometry. A major goal of the research – developing a realistic numerical model of the object analyzed, taking into account all the imperfections, determining the wall stress and strain state, exploring the places of extreme points, calculating the residual load bearing capacity of the tank and scrutinizing possible strengthening schemes for defective areas.

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Kołakowski, Zbigniew, and Andrzej Teter. "Coupled Static and Dynamic Buckling Modelling of Thin-Walled Structures in Elastic Range Review of Selected Problems." Acta Mechanica et Automatica 10, no. 2 (June 1, 2016): 141–49. http://dx.doi.org/10.1515/ama-2016-0023.

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AbstractA review of papers that investigate the static and dynamic coupled buckling and post-buckling behaviour of thin-walled structures is carried out. The problem of static coupled buckling is sufficiently well-recognized. The analysis of dynamic interactive buckling is limited in practice to columns, single plates and shells. The applications of finite element method (FEM) or/and analytical-numerical method (ANM) to solve interaction buckling problems are on-going. In Poland, the team of scientists from the Department of Strength of Materials, Lodz University of Technology and co-workers developed the analytical-numerical method. This method allows to determine static buckling stresses, natural frequencies, coefficients of the equation describing the post-buckling equilibrium path and dynamic response of the plate structure subjected to compression load and/or bending moment. Using the dynamic buckling criteria, it is possible to determine the dynamic critical load. They presented a lot of interesting results for problems of the static and dynamic coupled buckling of thin-walled plate structures with complex shapes of cross-sections, including an interaction of component plates. The most important advantage of presented analytical-numerical method is that it enables to describe all buckling modes and the post-buckling behaviours of thin-walled columns made of different materials. Thin isotropic, orthotropic or laminate structures were considered.

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44

Zhou, Xiaotao, Xiaofei Ma, Yesen Fan, and Huanxiao Li. "Tensile and bending behavior of thin-walled triaxial weave fabric composites." Journal of Engineered Fibers and Fabrics 14 (January 2019): 155892501989356. http://dx.doi.org/10.1177/1558925019893566.

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The laminate model of thin-walled triaxial weave fabric composites (hereinafter referred to as shell-membrane structure) to calculate the equivalent tensile Young’s modulus and bending stiffness is derived. Three-dimensional beam element finite element model of shell-membrane structure under different loading angles is established, and the tensile and bending properties of shell-membrane structure were simulated, respectively. Both results of laminate model and three-dimensional beam element finite element model verify the “size effect,” indicating that the shell-membrane structure can be equivalent to linear material in the small deformation range. And the shell-membrane structure exhibits an in-plane quasi-isotropic property. These two methods are convenient for the mechanical properties solving in engineering applications.

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45

Wang, Zhen Hong, Guo Xin Zhang, Yi Liu, and You Zhi Liu. "Study on the Application of Cooling Pipe in Thin-Walled Concrete Structure." Advanced Materials Research 163-167 (December 2010): 1107–10. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.1107.

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Cracks of concrete structure easily appear in the period of construction and the difference between the inside and outside temperature at early stage and the basic difference of the temperature at later stage are considered as the main factors causing cracks, so the temperature control becomes the key of problem. In view of this problem, this paper puts forward the pipe cooling technology which is usually used in the mass concrete to the thin-walled concrete structure. Under the basic theories of concrete temperature field and numerical algorithm of pipe cooling, the 3-D FEM is adopted to simulate the thermal field of concrete sluice with and without cooling pipe during construction. The results of comparison show that cooling pipe in thin-walled concrete structure can achieve better effect on temperature control, so it should have great reference signification to similar concrete projects in the future.

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46

Liu, S. J., and J. Chen. "RETRACTED: Fracture of thin-walled structure with SPH shell formulation." Thin-Walled Structures 48, no. 2 (February 2010): 118–26. http://dx.doi.org/10.1016/j.tws.2009.09.002.

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47

Chen, Xin, Jun Ping Wang, and Xin Yan. "Simplified Calculation of Internal Force of Steel Structure in Torsion." Applied Mechanics and Materials 444-445 (October 2013): 12–17. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.12.

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It cant be ignored when steel members generating forces and stresses in torsion. To get the exact results, you need to solve several higher order differential equations, and it is much difficult for actual engineering designs. Based on Elastic theory of thin-walled structures, this thesis tries to introduce an approximate, convenient and high-precision way to solve problems about torsion.

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48

Xu, Xun, Haidong Yu, Yunyong Li, and Xinmin Lai. "Compliant assembly deviation analysis of large-scale thin-walled structures in different clamping schemes via ANCF." Assembly Automation 40, no. 2 (November 3, 2019): 305–17. http://dx.doi.org/10.1108/aa-01-2019-0018.

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Purpose The structure stiffness is greatly affected by the fixture constraints during assembly due to the flexibility of large-scale thin-walled structures. The compliant deformation of structures is usually not consistent for the non-uniform stiffness in various clamping schemes. The purpose of this paper is to investigate the correlation between the assembly quality and the clamping schemes of structures with various initial deviations and geometrical parameters, which is based on the proposed irregular quadrilateral plate element via absolute nodal coordinate formulation (ANCF). Design/methodology/approach Two typical clamping schemes are specified for the large-scale thin-walled structures. Two typical deviation modes are defined in both free and clamping states in the corresponding clamping schemes. The new irregular quadrilateral plate element via ANCF is validated to analyze the compliant deformation of assembled structures. The quasi-static force equilibrium equations are extended considering the factors of clamping constraints and geometric deviations. Findings The initial deviations and geometrical parameters strongly affect the assembly deviations of structures in two clamping schemes. The variation tendencies of assembly deviations are demonstrated in details with the circumferential clamping position and axial clamping position in two clamping schemes, providing guidance to optimize the fixture configuration. The assembly quality of structures with deviations can be improved by configuration synthesis of the clamping schemes. Originality/value Typical over-constraint clamping schemes and deviation modes in clamping states are defined for large-scale thin-walled structures. The plate element via ANCF is extended to analyze the assembly deviations of thin-walled structures in various clamping schemes. Based on the proposed theoretical model, the effects of clamping schemes and initial deviations on the deformation and assembly deviation propagation of structures are investigated.

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Tse, P. C., and T. C. Lai. "An Expression for the Strain Energy of Laminated Composite Thin Shells." International Journal of Mechanical Engineering Education 23, no. 2 (April 1995): 169–77. http://dx.doi.org/10.1177/030641909502300213.

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An expression for the complementary strain energy of a linear elastic laminated composite thin-walled structure is presented which describes the energy in terms of midplane properties and subsequently stress and moment resultants rather than local stress and strain values. This expression is particularly useful for the analysis of statically indeterminate structures and energy storage devices such as springs.

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50

CIUBOTARIU, VLAD ANDREI, CRINA MARIA RADU, COSMIN GRIGORAȘ, and EUGEN HERGHELEGIU. "OBTAINING NEW THIN WALLED TUBULAR STRUCTURES THROUGH MATRIX MORPHOLOGICAL RESEARCH." Journal of Engineering Studies and Research 27, no. 1 (June 7, 2021): 33–38. http://dx.doi.org/10.29081/jesr.v27i1.249.

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New products based on a structure that represents a combination of known elements in a higher quality set, as well as products that refer to new shapes, new curves, new surfaces can be obtained logically - analytically - deductively or by methods specific to the optimal calculation. The present paper focuses on the method of analyzing tridimensional morphology, some possible solutions being evaluated on value criteria. Of course, these methods can be applied in the field of engineering with very good results. The focus of this study is to obtain new thin walled tubular structures - such as car crash members - which in the case of axial shock loads have a higher predictable behavior compared to those already used in various technical fields. Following the study, it can be said that depending on the amount of absorbed energy in the case of axial collisions and the absorption of kinetic energy developed at the time of impact, the optimal crashworthiness solution could be tubular structures with a circular support base and rectangular deformable area for impact.

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