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Abstract: Geocell reinforcement has been increasingly applied to embankment engineerings. Deformation calculation is one of the major concerns during the design process. Using Winkler foundation model and with consideration of the interface resistance effect, a deformation control differential equation for the geocell reinforced mattress under the vertical symmetric loads is presented in this paper. The corresponding power-series semi analytic solutions for the displacements and the internal forces of geocell reinforcement are also presented. Furthermore, the influence factors such as loads, length and flexural rigidity of geocell reinforcement, coefficient of subgrade reaction and the interface resistance on the stress-deformation characteristic of geocell reinforcement are discussed. Finally, two examples are employed to verify the presented method. This study suggests that the effect of the interface resistance on the deformation of geocell reinforcement should be considered in engineering design. [Copyright &y& Elsevier]

Abstract  Based on the design sensitivity analysis for structural dynamics in time domain, an integrated control–structural design optimization method is proposed to the vibration control of piezoelectric intelligent truss structure. In this investigation, the objective function and constraint functions include not only the conventional design indexes of structure but also the vibration control indexes and the feedback control variables. The structural design variables are optimized simultaneously with the vibration control system. The sensitivity relations for the control–structure optimization model are derived by using a new method, and the sequential linear programming algorithm is used to solve this kind of optimization problem. The numerical examples given in the paper demonstrate the effectiveness of methods and the program. [ABSTRACT FROM AUTHOR]

Abstract: As a rule, the change in mechanical properties of rock by specimen size is regarded as scale effect. A rock mass basically consists of two components: intact rock and discontinuities, each of which has different scale effects. In order to numerically analyze the behavior of discontinuous rock masses, sufficient mechanical properties must be determined not only for discontinuities but also for intact rock taking into consideration the different scale effects. This paper reviews the scale effect on strength and deformation characteristics of intact rock, and also discusses the possibility of using standard specimens to estimate strength and deformation characteristics of actual-scale rock. Finally, we propose an adequate method for the practical determination of mechanical design parameters based on the above discussions. [Copyright &y& Elsevier]

This paper describes a novel cumulative fatigue damage life predictive model aimed at providing the design engineer an easy fatigue life predictive tool using experimental data. This encompasses an integrated approach of joint testing, analysis, and modeling. For this purpose, joints were prepared using stainless steel adherend specimens and a commercial silver-filled electronically conductive adhesive, and tested under monotonic and cyclic fatigue conditions, at 28°C, 20% relative humidity. Load–number of cycles (P–N) curves were generated for these specimens using load ratio R = 0.1 and R = 0.5 (R = Pmin/Pmax = σmin/σmax) at a cyclic frequency of 150 Hz. Fatigue life and failure behaviors due to cumulative fatigue damage were assessed using a novel experimental program. Experimental results revealed that most of the fatigue damage occurs during the latter part of the fatigue process and the combination of lower load ratio and higher maximum applied load has the most detrimental effect on the failure of the joint. Finally, a novel analytical model for fatigue life prediction under variable cyclic conditions was proposed using experimental data and a detailed stress analysis. [ABSTRACT FROM AUTHOR]

Arrow’s theorem poses limits to the translation of the different preference orders on a set of options into a single preference order. In this paper, I argue, against opinions to the contrary, that Arrow’s theorem applies fully to multi-criteria decision problems as they occur in engineering design, making solution methods to such problems subject to the theorem’s negative result. Discussing the meaning and consequences for engineering design, I review the solution methods to such problems presented in the engineering design literature in the light of the theorem. It appears that underlying such methods is a mix-up of two fundamentally different problem definitions, as the theory of multi-attribute preferences, which is often presented as an adequate approach for engineering design, in fact fails to address the Arrowian multi-criteria problem. Finally, I suggest ways how engineering design might adopt results from discussions of Arrow’s theorem elsewhere in resolving its multi-criteria decision problems. [ABSTRACT FROM AUTHOR]

Engineering design research shows a rather fragmented, if not a chaotic, picture. But does it have a hidden order? Can we explore it, or should we impose a reasoning model? This paper looks for the answer in the purpose of engineering design. It is destined to sustain human existence and well being by virtual creation of artifacts and services for the society. To this end, the engineering design discipline should provide a proper body of knowledge. The design knowledge obtained by empirical exploration and/or rational comprehension should be transformed for practical/pragmatic deployment. It was assumed that this purposely streaming of design knowledge gives a unique rationale for engineering design research. Based on this, a framework of reasoning was constructed, including source, channel, and sink categories of knowledge and research of engineering design, respectively. Within each category, research domains, trajectories, and approaches were identified. The semantic relationships of domains, trajectories, and approaches form a hierarchical structure. The proposed framework enables a grounded argumentation about the order of engineering design research, as well as about the articulation of the engineering design knowledge. [ABSTRACT FROM AUTHOR]

This paper addresses the experimental and numerical analysis of a novel design of adhesive joint. So the consistency of the data could be verified, a statistical study was performed that considered not only the sample size population but also the statistical differences between the single-lap and wavy-lap joints. In addition to experimental tests, a finite element analysis was carried out to analyze the stress fields inside the joints. The results show an average increase of nearly 41% on loading. This fact could be due to the compressive stress field developed inside the wavy-lap joint. Moreover, this stress field distribution can also be the reason for the adherent delamination observed in the wavy-lap joints. So far, the modified wavy-lap joint seems to lead to stronger joints. [Copyright &y& Elsevier]

This paper presents an analysis of the structural features of trees in order to understand how high levels of mass-efficiency are achieved and to identify lessons for engineering designers. Structural features are identified from a literature survey and also by observations and measurements of mature trees in the UK. The functions of the structural features are identified using a function-means tree. The mass-efficiency of the structural features is modelled and assessed using first-order stress analysis. A comparison is made between the structural features found in trees and those used in engineering. There are many similarities between the structural features in trees and engineering. However, there are a few aspects that are mostly unique to trees such as the existence of important non-structural functions in structural members and the presence of adaptive growth. These features may indicate how future engineering structures will be designed. [ABSTRACT FROM AUTHOR]