Sensitivity analysis of stress distribution in bicycle frame

New Generation Large Aircrafts became a new member of China large airports. However, its heavy weight and high contact pressure would have great impact on the flexible runway pavement. in this paper, based on the multilayered elastic theory, the tensile stress distribution under different airplane was studied to obtain the critical load positions. Furthermore, parameter sensitivity analysis was conducted, including thickness and modulus of Asphalt Stabilized Base (ATB) layer. Results indicated that increasing ATB thickness can only decrease the tensile stress a little, and increasing the modulus of the ATB layer will be more efficient than increasing its thickness. Finally pavement design suggestions composing of both the structural and material considerations were proposed.

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A New Design of a Bicycle Frame: An Example for an Effective Layout Procedure Based on FE-Simulation of Biological Growth

20th Design Automation Conference: Volume 2 — Robust Design Applications; Decomposition and Design Optimization; Optimization Tools and Applications ◽

10.1115/detc1994-0144 ◽

1994 ◽

Author(s):

A. Baumgartner ◽

C. Mattheck

Keyword(s):

Fatigue Life ◽

Stress Distribution ◽

Considerable Increase ◽

Fe Simulation ◽

Lightweight Design ◽

Lightweight Structures ◽

Biological Growth ◽

Bicycle Frame ◽

High Fatigue ◽

Homogeneous Stress

Abstract On the basis of the axiom of constant stress two optimization procedures have been developed for the improvement of technical load carriers. Specially the goals of lightweight design and high fatigue resistance are considered. The SKO method generates lightweight structures for a defined loadcase by simulating the adaptive mineralization of bones. A subsequent shape optimization with the CAO method results in a design with a homogeneous stress distribution on the surface. This prevention of localized high stresses leads to a considerable increase in fatigue life. With the example of a new bicycle frame the efficiency of a combination of both to a complete layout procedure is demonstrated.

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The concerted use of SEM, TEM, and SCM for examination of resin-dentin interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170116 ◽

1994 ◽

Vol 52 ◽

pp. 476-477

Author(s):

B. Van Meerbeek ◽

L. J. Conn ◽

E. S. Duke

Keyword(s):

Surface Layer ◽

Stress Distribution ◽

Phosphoric Acid ◽

Bonding Mechanism ◽

Restorative Dentistry ◽

Dental Adhesive ◽

Low Viscosity ◽

Dentin Adhesives ◽

Acid Etch ◽

Tooth Tissue

Restoration of decayed teeth with tooth-colored materials that can be bonded to tooth tissue has been a highly desirable property in restorative dentistry for many years. Advantages of such an adhesive restorative technique over conventional techniques using non-adhesive metal-based restoratives include improved restoration retention with minimal sacrifice of sound tooth tissue for retention purposes, superior adaptation and sealing of the restoration margins in prevention of caries recurrence, improved stress distribution across the tooth-restoration interface throughout the whole tooth, and even reinforcement of weakened tooth structures. The dental adhesive technology is rapidly changing. An efficient resin bond to enamel has already long been achieved. Its bonding mechanism has been fully elucidated and has proven to be a durable and reliable clinical treatment. However, bonding to dentin represents a greater challenge. After the failures of a dentin acid-etch technique in imitation of the enamel phosphoric-acid-etch technique and a bonding procedure based on chemical adhesion, modern dentin adhesives are currently believed to bond to dentin by a micromechanical hybridization process. This process is developed by an initial demineralization of the dentin surface layer with acid etchants exposing a collagen fibril arrangement with interfibrillar microporosities that subsequently become impregnated by low-viscosity monomers. Although the development of such a hybridization process has well been documented in the literature, questions remain with respect to parameters of-primary importance to adhesive efficacy.

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