D.W. Kelly, P. Hsu and M. Asudullah
A procedure for plotting load paths and load flow in structures from a finite element analysis is described. The load flow is indicated by pointing vectors and the load paths are…
Abstract
A procedure for plotting load paths and load flow in structures from a finite element analysis is described. The load flow is indicated by pointing vectors and the load paths are determined by plotting contours tangent to these vectors. The procedure is applied to assembled structures. An explanation is given for “eddies” that can appear in regions not contributing to the load path.
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Ying Yu, Huan Huang, Shuo Wang, Shuaishuai Li and Yu Wang
The mesoscale structure (MS) has a significant impact on the mechanical performance of parts made by additive manufacturing (AM). This paper aims to explore the design and…
Abstract
Purpose
The mesoscale structure (MS) has a significant impact on the mechanical performance of parts made by additive manufacturing (AM). This paper aims to explore the design and fabrication of force-flow guided reinforcement mesoscale structure (FFRMS) compared with the homogeneous mesoscale structure (HMS), which is inconsistent with the stress field for a given load condition. Some cases were presented to demonstrate the mechanical properties of FFRMS in terms of MS combined with quasi-isotropy and anisotropy.
Design/methodology/approach
The paper consists of four main sections: the first developed the concept of FFRMS design based on HMS, the second explored volume fraction control for the proportion of force-flow lines in terms of mechanical property requirement, and the third presented a sequence stacking theory and practical manufacturing process framework and the final sections provided some application case studies.
Findings
The main contributions of this study were the definition and development of the FFRMS concept, the application framework and the original case studies. As an example, a typical lug designed with the proposed FFRMS method was fabricated by three different AM processes. The test results showed that both the strength and stiffness of the specimens are improved greatly by using the FFRMS design method.
Originality/value
The superposition of HMS as the basement and force-flow as an indication of the stiffener, leading to a heterogeneous structure, which exhibits more efficient and diversified means compared with the traditional way of increasing the HMS density merely.
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Donald W. Kelly, Carl A. Reidsema and Merrill C.W. Lee
The purpose of this paper is to describe a post‐processing procedure for defining load paths and a load bearing topology using the stresses from a finite element analysis.
Abstract
Purpose
The purpose of this paper is to describe a post‐processing procedure for defining load paths and a load bearing topology using the stresses from a finite element analysis.
Design/methodology/approach
Cauchy stress vectors and a Runge‐Kutta algorithm are used to identify the paths being followed by load components aligned with the coordinate axes. An algorithm is then defined which identifies an efficient topology that will carry the loads by straightening the paths.
Findings
The aim of the algorithm is to provide insight into the way a structure is carrying loads by identifying the material most effective in performing the load transfer. The procedure is applied to a number of structures to demonstrate its applicability to structural design.
Research limitations/implications
The examples demonstrate an insight of structural behavior that is useful at the conceptual stage of the design process. The load paths identify load transfer and warn the designer of the creation of bending moments and the location of features such as holes on the load path. They also demonstrate that the new procedures can provide suggestions for alternate topologies for the load bearing structure.
Originality/value
The load path theory has been published elsewhere. The new work in this paper is the definition of the Runge‐Kutta algorithm to define the paths and the algorithm to identify the topology performing the load transfer.