Construction of structural design guidelines for vacuum vessels and other components

Porous asphalt pavements allow designers to introduce more sustainability into projects and lessen their environmental impact. Current design procedures are based primarily on hydrologic considerations; comparatively little attention has been paid to their structural design aspects. As their use grows, a design procedure and representative material structural properties are needed to ensure that porous pavements do not deteriorate excessively under traffic loads. The objective of this project was to develop a simple, easy to apply design procedure for the structural design of porous asphalt pavements. Two methodologies were considered for such a structural design procedure: ( a) the 1993 AASHTO Pavement Design Guide empirical approach, and ( b) the mechanistic–empirical approach employed by the AASHTOWare Pavement ME Design software. A multifactor evaluation indicated the empirical 1993 AASHTO design procedure to be the most appropriate platform at this time. It is noted, however, that both design procedures lack validation of porous asphalt pavements against field performance. AASHTO design parameters and associated material characteristics are recommended, based on an extensive literature review. For “thin” open-graded base structures (12 in. or less), the AASHTO procedure is performed as published in the 1993 Guide. For “thick” base structures (>12 in.), the base/subgrade combination is considered a composite system which supports the porous asphalt layer; an equivalent deflection-based approach is described to estimate the composite resilient modulus of the foundation system, prior to applying the 1993 AASHTO design procedure.

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Improving neural hardware performance with network structural design guidelines

Proceedings of 1994 IEEE International Conference on Neural Networks (ICNN'94) ◽

10.1109/icnn.1994.374463 ◽

2002 ◽

Author(s):

D. Naylor ◽

S. Jones

Keyword(s):

Structural Design ◽

Design Guidelines ◽

Hardware Performance

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Elliptical hollow section T and X connections

Canadian Journal of Civil Engineering ◽

10.1139/l2012-081 ◽

2012 ◽

Vol 39 (8) ◽

pp. 925-936 ◽

Cited By ~ 6

Author(s):

Tarana Haque ◽

Jeffrey A. Packer

Keyword(s):

Construction Industry ◽

Structural Design ◽

Failure Modes ◽

Design Method ◽

Design Guidelines ◽

Preliminary Design ◽

Hollow Section ◽

Steel Shape ◽

Circular Hollow Section ◽

Angle Orientation

Elliptical hollow sections (EHS) are the newest steel shape to have emerged in the construction industry. They have been incorporated in a variety of structures around the world, including Canada, without structural design guidelines. To date, EHS are completely absent from Canadian codes and guides. A possible application of EHS is within truss-systems and, as such, a research project has been undertaken to investigate the behaviour of EHS-to-EHS welded connections. Twelve T and X connection tests have been performed to study the effect of connection angle, orientation type, and loading sense. Two methods to predict connection capacities and failure modes are investigated: an equivalent circular hollow section (CHS) approach and an equivalent rectangular hollow section (RHS) approach. The equivalent RHS approach proved to be more successful at capturing the actual failure mode of welded EHS-to-EHS connections and is therefore recommended at this time as a preliminary design method for EHS truss-type connections.

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Structural Design of Asphalt Pavements: Principles and Practices in Various Design Guidelines

Transportation in Developing Economies ◽

10.1007/s40890-015-0004-3 ◽

2015 ◽

Vol 1 (1) ◽

pp. 25-32 ◽

Cited By ~ 3

Author(s):

Animesh Das

Keyword(s):

Structural Design ◽

Design Guidelines ◽

Asphalt Pavements

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The Effect of Service Installations on Structural Integrity of Slabs in Buildings

Tanzania Journal of Engineering and Technology ◽

10.52339/tjet.v33i1.450 ◽

2010 ◽

Vol 33 (1) ◽

pp. 18-28

Author(s):

Ladslaus Lwambuka

Keyword(s):

Reinforced Concrete ◽

Bearing Capacity ◽

Structural Design ◽

Design Guidelines ◽

Cross Sectional Area ◽

Sectional Area ◽

Structural Element ◽

Load Bearing Capacity ◽

Cross Sectional ◽

Load Bearing

In building construction industry service installations, usually housed in conduit pipes, are commonly mounted inside reinforced concrete structural elements. This practice is adopted to attain aesthetical outlook at both interior and exterior surfaces of the buildings. Depending on the extent of service installations, the cross sectional area of the load bearing structural member is substantially reduced. However, the current structural design guidelines have no provision to accommodate the extent to which the existence of conduit pipes impairs the load bearing capacity of the structural element though reduced cross sectional area. This study has attempted to address this gap in structural design ofbuildings; it involves assessing the current design practice of considering a structural element as a full solid body and comparing its ultimate load bearing capacity with the ones containing the conduit pipes. The study findings are based on test results from laboratory experiments on reinforced concrete slab models with varying intensity of conduit pipeinstallations as commonly practiced on construction sites. Recommendations are put forth when and how to consider the reduced load bearing capacity through the existence of service installations as part of structural engineering designs.

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Present activities for the preparation of a Japanese draft of structural design guidelines for the experimental fusion reactor

Fusion Engineering and Design ◽

10.1016/0920-3796(95)00433-5 ◽

1996 ◽

Vol 31 (2) ◽

pp. 145-165 ◽

Cited By ~ 3

Author(s):

K. Miya ◽

Y. Muto ◽

H. Takatsu ◽

K. Hada ◽

K. Koizumi ◽

...

Keyword(s):

Structural Design ◽

Fusion Reactor ◽

Design Guidelines ◽

Experimental Fusion

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A Proposed Design Criterion for Vessel Lifting Lugs in Lieu of ASME B30.20

Design and Analysis of Piping, Vessels, and Components ◽

10.1115/pvp2002-1280 ◽

2002 ◽

Author(s):

Dennis K. Williams

Keyword(s):

Structural Design ◽

The United States ◽

Pressure Vessels ◽

Design Guidelines ◽

Design Criterion ◽

Hertzian Contact ◽

Safety Standard ◽

Analysis Techniques ◽

Large Pressure ◽

Repetitive Loading

This paper describes a method for evaluating the structural adequacy of various lifting lugs utilized in the erection and up righting of large pressure vessels. In addition, the analysis techniques are described in detail and design guidelines for vessel lifting are tendered. The statutory and provincial regulations in both the United States and the province of Alberta, Canada are also reviewed and discussed with respect to the too often utilized phrase “factor of safety” (FOS). The implied implications derived from the chosen FOS are also outlined. A discussion is presented as to the applicability of the ASME safety standard B30.20 [1] entitled, “Below the Hook Lifting Devices” and as to the severe shortcomings of the safety standard in its attempt to delve into the design of lifting devices, especially when applied to lifting lugs on large and heavy-weight pressure vessels. Exemplar lugs on vessels are defined and the finite element analyses and closed form Hertzian contact problem solutions are presented and interpreted in accordance with the proposed design criteria. These results are compared against the very limited design information contained within ASME B30.20 [1]. Suggestions for the revision and applicability of the Below the Hook Lifing Devices safety standard and presented and discussed in light of the examples and technical justification presented in the following paragraphs. In addition, the silence of the referenced safety standard on the very large contact stresses that are well known to exist between a lifting pin and clevis type geometry is also discussed. Due to the limited number of repetitive loading cycles that vessel lifting lugs acturally experience during the service life of a vessel, a recommendation is made to either clearly exclude vessel lifting lugs from the scope of ASME B30.20 [1] or to specifically include a separate design and analysis section within the referenced stardard to properly address the mechanical and structural design issues applicable to pressure vessel lifting lugs.

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Structural design of floodways under extreme flood loading

International Journal of Disaster Resilience in the Built Environment ◽

10.1108/ijdrbe-10-2019-0072 ◽

2020 ◽

Vol 11 (4) ◽

pp. 535-555

Author(s):

Isaac Greene ◽

Weena Lokuge ◽

Warna Karunasena

Keyword(s):

Finite Element ◽

Design Process ◽

Structural Design ◽

Design Guidelines ◽

Flood Events ◽

Worst Case ◽

Content Type ◽

Design Charts ◽

Hydraulic Design ◽

Extreme Flood

Purpose Current methods for floodway design are predominately based on hydrological and hydraulic design principles. The purpose of this paper is to investigate a finite element methods approach for the inclusion of a simplified structural design method into floodway design procedures. Design/methodology/approach This research uses a three-dimensional finite element method to investigate numerically the different parameters, geometric configurations and loading combinations which cause floodway vulnerability during extreme flood events. The worst-case loading scenario is then used as the basis for design from which several structural design charts are deduced. These charts enable design bending moments and shear forces to be extracted and the cross-sectional area of steel and concrete to be designed in accordance with the relevant design codes for strength, serviceability and durability. Findings It was discovered that the analysed floodway structure is most vulnerable when impacted by a 4-tonne boulder, a 900 mm cut-off wall depth and with no downstream rock protection. Design charts were created, forming a simplified structural design process to strengthen the current hydraulic design approach provided in current floodway design guidelines. This developed procedure is demonstrated through application with an example floodway structural design. Originality/value The deduced structural design process will ensure floodway structures have adequate structural resilience, aiding in reduced maintenance and periods of unserviceability in the wake of extreme flood events.

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