Case Study on Effect of Static and Dynamic Loads on Hyperboloid Shell Structure

The ASME pressure vessel and piping codes and standards provide excellent references for code writers in international jurisdictions when developing their own national codes and for safety authorities when developing regulatory acts. The inclination to customize this effort may add unnecessary complexity that unintentionally obscures the underlying engineering principles. In developing the Canadian pipeline code, the authors use the notion of maximum operating pressure or MOP similar to the MOP found in the ASME codes for pipelines. While the ASME code definitions are explicit and articulate, the MOP defined in the Canadian code is less so and has led to inadvertent confusion by industry users. Misunderstanding of complementary terminology used in ancillary ASME standards has contributed to further complexities. The use of the term, maximum allowable operating pressure or, MAOP in the ASME pipeline codes has further reduced clarity when integrating this term into international codes and regulatory acts. This paper examines, in detail, some aspects of the Canadian pipeline code and illustrates via a representative case study some of the aforementioned difficulties that have arisen. These difficulties resulted in unnecessary derating of assets by imposing operational limits that were well below actual capacity. A clear explanation of the engineering principles underlying the provisions for codes which use a “design by rules” philosophy will help operators set appropriate limits for both static and dynamic loads that may not be apparent in the specific codes considered and will be expository for regulators and code users in general.

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New Research on the Use of Hardening Plastics for Aircraft Construction

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100104961 ◽

1940 ◽

Vol 44 (349) ◽

pp. 44-73

Author(s):

Wilhelm Kuech

Keyword(s):

Strength Properties ◽

Dynamic Loads ◽

Absorbed Energy ◽

Good Strength ◽

Different Temperatures ◽

Bonding Properties ◽

Static And Dynamic Loads ◽

Impact Bending ◽

New Research ◽

Laminated Materials

Laminated materials incorporating plastics seem to be especially well suited lor highly stressed aircraft components, by reason of their good strength properties. Paper, fabric and wood veneers treated with plastics on a phenolic basis were tested with regard to their strength, especially in bending, shear, absorbed energy in impact bending, notching strength and in their resistance against moisture. Further, the behaviour of compressed plastics was studied at different temperatures under static and dynamic loads. A part of the research was extended to pure phenol resin and to thermoplastics based on methacrylate and polyvinylchloride. The bonding properties of laminated compressed plastics were established. Concluding, some experiments relating to the practical manufacture of aeroplane components are communicated.

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Preliminary investigation of use of flexible folding wing tips for static and dynamic load alleviation

The Aeronautical Journal ◽

10.1017/aer.2016.108 ◽

2016 ◽

Vol 121 (1235) ◽

pp. 73-94 ◽

Cited By ~ 19

Author(s):

A. Castrichini ◽

V. Hodigere Siddaramaiah ◽

D.E. Calderon ◽

J.E. Cooper ◽

T. Wilson ◽

...

Keyword(s):

Aspect Ratio ◽

Preliminary Investigation ◽

Aircraft Design ◽

Dynamic Loads ◽

Induced Drag ◽

Aeroelastic Model ◽

Static And Dynamic Loads ◽

Folding Wing ◽

Wing Tips ◽

Wing Tip

ABSTRACTA recent consideration in aircraft design is the use of folding wing-tips with the aim of enabling higher aspect ratio aircraft with less induced drag while also meeting airport gate limitations. This study investigates the effect of exploiting folding wing-tips in flight as a device to reduce both static and dynamic loads. A representative civil jet aircraft aeroelastic model was used to explore the effect of introducing a wing-tip device, connected to the wings with an elastic hinge, on the load behaviour. For the dynamic cases, vertical discrete gusts and continuous turbulence were considered. The effects of hinge orientation, stiffness, damping and wing-tip weight on the static and dynamic response were investigated. It was found that significant reductions in both the static and dynamic loads were possible. For the case considered, a 25% increase in span using folding wing-tips resulted in almost no increase in loads.

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The Mechanical Properties Comparative Analysis for Socked and Non-Socketed Composite Pile

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.748 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 748-750

Author(s):

Heng Chen ◽

Ke Sheng Ma

Keyword(s):

Mechanical Properties ◽

Comparative Analysis ◽

Seismic Performance ◽

Dynamic Loads ◽

Vertical Load ◽

Interlayer Thickness ◽

Static Loads ◽

Soil Stress ◽

Composite Pile ◽

Static And Dynamic Loads

For socked and non-socketed piles in the different mechanical behavior under static and dynamic loads, the paper use ABAQUS to model, simulate the pile , the soil interlayer thickness between the bottom of the pile and bedrock are 2m, 4m under vertical load and Earthquake, cushion cap, pile and pile soil stress situation found non-socketed piles when the soil interlayer thickness within a certain range, the composite pile small subside under dynamic, static loads, the non-socketed piles can better take advantage of the pile soil has a good seismic performance in the earthquake.

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DIGITAL FABRICATION AS A LEARNING MEDIA FOR LIGHTWEIGHT STRUCTURE WITH CASE STUDY OF SHELL STRUCTURE

MODUL ◽

10.14710/mdl.21.2.2021.126-133 ◽

2021 ◽

Vol 21 (2) ◽

pp. 126-133

Author(s):

Stephanus Evert Indrawan ◽

LMF Purwanto

Keyword(s):

Shell Structure ◽

Laser Cutting ◽

Digital Fabrication ◽

Scalar Model ◽

Structure System ◽

Lightweight Structures ◽

Digital Devices ◽

Lightweight Structure ◽

Realization Process

The lightweight structure system is an effort to optimize the structure to distribute the load efficiently. Unfortunately, students often have difficulty imagining the learning outcomes application in the real world when studying light structural systems. However, the use of the scalar model can still explain several essential aspects of a lightweight structural system, one of which is the effect of connection and formation of material components on the structural capability. Therefore, this paper aims to bridge the learning process by utilizing digital devices from the concept stage of structural modeling with the help of software (Rhinoceros, Grasshopper, and Kangaroo) to the realization process using laser cutting. The method used is a semi-experimental method that applies Hooke's law principle, which produces a shell structure system with a digital fabrication approach that utilizes a lightweight material, namely, corrugated paper board, as the primary material. This paper concludes that digital technology and digital fabrication processes can help students understand the concept of lightweight structures because they can use computer simulations, cut them using laser cutting, and assemble them in the field in a series of simultaneous processes.

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Manufacturing of Bellows Compensator by Pulsed-Magnetic Field Pressure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1049.108 ◽

2022 ◽

Vol 1049 ◽

pp. 108-113

Author(s):

Nikolay Kurlaev ◽

Ahmed Soliman Mohamed Sherif ◽

Nikolay Ryngach

Keyword(s):

Relative Elongation ◽

Operating Time ◽

Dynamic Loads ◽

Pulse Field ◽

Magnetic Pulse ◽

System Operation ◽

Effective Protection ◽

Expansion Joints ◽

Static And Dynamic Loads ◽

Tubular Billet

Bellows are a cylindrical shell with a corrugated part, widely used in aviation engineering as a movable sealing element to balance pressure and temperature differences, which ensure continuous and accurate system operation. The use of bellows expansion joints provides reliable and effective protection of pipelines from static and dynamic loads arising from deformations and vibration. Welded-edge bellows are a popular choice for regulating and controlling fuel supply in aircraft devices. The ability of the compensator to perceive deformations is determined by its assigned operating time, which describes how many cycles, and with what amplitude, the bellows compensator perceives without damage. A method for stamping bellows from tubular billets by using magnetic-pulse field in rigid dies, including sequential shaping of corrugations by distributing the internal magnetic pressure with axial movement of the free end of a tubular billet, characterized in that the material of the tubular billet for shaping corrugations is selected in accordance with its relative elongation.

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