Papers by Keyword: Mechanical Analysis

Abstract: Additive manufacturing (AM) techniques are based on the process of joining materials, layer upon layer, differently from subtractive manufacturing methods. The design for AM allows for the creation of complex shapes as well as for the improvement of the performance of critical components in several fields, spanning from aerospace and automotive to biomedical applications. On the other hand, unlike man-made high load-bearing capacity devices, which are usually dense solids, nature uses mesoscopic or microscopic cellular structures as a fundamental support for the design. The increasing applications of AM in industrial production have led to product reimagination from a novel standpoint, enabling the fabrication of advanced lattice structures using polymer-based materials. Over the past few years, many efforts have been made to develop strategies for finding the design which is best suited to the requirements. In the current research, specific design scenarios were explored, the aim being to develop novel lattice structures for energy absorption, using an AM technique (i.e., fused deposition modelling) and a modified Acrylonitrile Styrene Acrylate (ASA)-based material. The fabricated structures were preliminarily analysed by means of compression tests.

Abstract: Catapults are war instruments that have been used for centuries; the author of the first catapult is not known with certainty, although many scholars agree that their first appearance could have occurred in China. At first, they were operated by human power, with a dozen men pulling a rope to run the mechanism. Later came the trebuchet, an invention attributed to Mardi Ibn Ali al-Tarsusi, a type of catapult that uses the potential energy of a counterweight to launch the projectile further and with more power than with the old catapults. Today, we can find several mechanisms that use the same principle as the trebuchet. In this work, the geometrical modelling, the mechanical analysis, its functioning, and the actual scale reproduction of the device are carried out.

Abstract: Additive Manufacturing technologies allow for the direct fabrication of lightweight structures with improved properties. In this context, Fused Deposition Modelling (FDM) has also been considered to design 3D multifunctional scaffolds with complex morphology, tailored biological, mechanical and mass transport properties. As an example, poly (ε-caprolactone) (PCL), surface-modified PCL and PCL-based nanocomposite scaffolds were fabricated and analysed. The effects of structural and morphological features (i.e., sequence of stacking, fiber spacing distance, pore size and geometry), surface modification and nanoparticles on the in vitro biological and mechanical performances were investigated.

Abstract: In this paper, the mechanics equation of the dynamic compaction machine arm frame is established based on the theory of statics, the arm lifting rope force is given, the influence of the wire rope force with relative position parameters changing is also discussed. The critical factors that affect the arm lifting rope force are identified. Compared the simulation and the test results, the major forces errors are less than 8%. The correctness of the theoretical study and simulation are verified. The research results could be used for the arm wire rope type selection of the dynamic compaction.

Abstract: Mechanical analysis of flexible pipe during installation is presented in this paper. The configuration, tension and bending moment of the flexible are important issues during the installation. A reasonable theoretical model is proposed to handle the pipe configuration and the loads during installation. Numerical iteration program for the model is developed to get the tension, bending moment distribution and the pipe configuration. Two segments which are suspended segment and seabed segment are analyzed with different calculation model for their different load conditions and boundary conditions. Finite element model is established by Abaqus to verify the results from the theoretical model. The results from theoretical are very close to the ones got from FEM. Typical installation method J-lay method is applied to perform the FEM and numerical analysis.

Abstract: Partial load has great impact on both service life and security design of scissor transmission mechanism. A mechanical model has been established, on the assumption that the scissor units are rigid bodies and the connecting rods are elastic bodies, for the research on the scissor transmission mechanism considering partial load. The recursive matrix used to calculate the node force of multi-unit transmission mechanism has been obtained. And based on the recursive matrix, the method has been deduced to calculate the node force of the scissor transmission mechanism in the unbalanced loading condition after the connecting rods were replaced by equivalent models—the springs. The finite element model carried out with SAP84 was established to measure the accuracy of the equations obtained by theory derivation, and the results proved the correctness of the theoretical formula because of the little difference between theoretical results and simulation results. The conclusion obtained could serve as theoretical guidance for mechanical analysis and optimal design on scissor transmission mechanism in the unbalanced loading condition and reference for elastomeric scissor unit research.

Abstract: In order to know seismic damage characteristics of multi-story brick masonry structure and improve its seismic capability, five kinds of earthquake damage or collapse forms of multi-story masonry brick structure are summed up based on earthquake disaster survey, each of which is analyzed with mechanics. And the failure mechanism of each seismic damage form of multi-story brick masonry structure are proposed, which provides effective engineering experience for the seismic or anti-collapse design of multi-story masonry brick structure. The research has the important significance in improving the seismic capacity of multi-story brick masonry structure and reducing the earthquake casualties.

Abstract: With the operation of the power engineering, such as west-east electricity transmission, the outside sending of the three gorges, areas network and so on, many large span engineering emerged in different part of China. And among it, the key point of the whole subject is the design of the structure. This essay aims mainly at introducing the history and modern application of steel tube tower. Meanwhile do the analysis comparison for the modeling of the transmission tower according to angle steel tower and steel tube tower under the working condition of high winds. Steel tube tower is better because it is smaller in shape factor of wind load than angle steel tower, so it can reduce the tower weight and fundamental effort, the economical advantage is great.

Abstract: This paper has a comprehensive analysis of the cloud logistics development momentum, in view of the commercial mode theory of Alexander Osterwalder. In combination with the three aspects of assets management such as the allocation of resources, core competitiveness and the partner network , this paper lists the commercial mode analysis of XingChenJiBian Company (STARS EXPRESS).Finally, the current problems and developing trend of cloud logistics mode under e-commerce have been sorted out.And the future of cloud logistics has been prospected in the paper based on the development of cloud logistics.

Abstract: The force of the concrete pumping work of mine rotor wet spraying machine is analysis in this paper, focusing on the piston assembly and cylinder bore rotor stress analysis during nesting, selecting the important structural parameters and optimizing the structure, to ensure the normal and efficient function of wet spraying working to improve the stability of wet spray machine work and life, and providing an important reference for the structural design of the piston assembly.