Design Guidelines for Doubler Plate Repairs of Ship Structures

2005 ◽  
Author(s):  
Pradeep K. Sensharma ◽  
Malcolm Willis ◽  
Aaron Dinovitzer ◽  
Nat Nappi
Keyword(s):  
Engineering Design ◽  
Low Cost ◽  
Design Guidelines ◽  
Performance Data ◽  
Ship Structures ◽  
Buckling Strength ◽  
Relative Ease ◽  
Fatigue And Fracture ◽  
Fracture Assessment ◽  
Design Guidance

The use of doubler plates or ‘doublers’ has become routine for temporary ship repairs. It is the preferred method for ships’ structural repairs for plate corrosion due to its relative ease and low cost of installation over the more costly permanent welded plate insert repair. A lack of performance data and engineering design guidance are the reasons that repairs with doublers are currently considered only temporary. This objective of this study was to develop a set of guidelines for designing and applying doubler plate repairs to ship structures. The guidelines were established using the following criteria: various stress analyses, buckling strength, corrosion types and rates, weld types, and doubler plate fatigue and fracture assessment. Studying and understanding doubler plate repair performance by comparison to that of the primary hull performance allows critical operational decisions to be made with greater ease and confidence. However, the ultimate goal of this study was to establish the design and limitations on the applications of doubler plate repairs for surface ships.

Design Guidelines for Doubler Plate Repairs of Ship Structures

2006 ◽  
Vol 22 (04) ◽  
pp. 219-238
Author(s):  
Pradeep K. Sensharma ◽  
Malcolm Willis ◽  
Aaron Dinovitzer ◽  
Nat Nappi
Keyword(s):  
Engineering Design ◽  
Low Cost ◽  
Design Guidelines ◽  
Performance Data ◽  
Ship Structures ◽  
Buckling Strength ◽  
Relative Ease ◽  
Fatigue And Fracture ◽  
Fracture Assessment ◽  
Design Guidance

The use of doubler plates or "doublers" has become routine for temporary ship repairs. It is the preferred method for ship structural repairs for plate corrosion due to its relative ease and low cost of installation over the more costly permanent welded plate insert repair. A lack of performance data and engineering design guidance are the reasons that repairs with doublers are currently considered only temporary. The objective of this study was to develop a set of guidelines for designing and applying doubler plate repairs to ship structures. The guidelines were established using the following criteria: various stress analyses, buckling strength, corrosion types and rates, weld types, and doubler plate fatigue and fracture assessment. Studying and understanding doubler plate repair performance by comparison to welded plate insert repair performance in the primary hull allows critical operational decisions to be made with greater ease and confidence. However, the ultimate goal of this study was to establish the design and limitations on the applications of doubler plate repairs for surface ships.

scholarly journals Community engagement in developing urban design guidance for heritage sites: The case of Bursa, Turkey

Urbani izziv ◽  
2019 ◽  
Vol 2 (30) ◽  
pp. 70-84
Author(s):  
Sibel Polat ◽  
H. Özge Tümer Yıldız
Keyword(s):  
Cultural Heritage ◽  
Community Engagement ◽  
Urban Design ◽  
Design Guidelines ◽  
Guidance System ◽  
Rapid Urbanization ◽  
Heritage Sites ◽  
Heritage Site ◽  
Design Guidance

In recent years, central and local governments have carried out studies to establish a legal administrative infrastructure for urban design and to develop urban design guidance to preserve the identity of historic cities under the pressure of rapid urbanization in Turkey. The main aim of this article is to explain how we implemented a participatory urban design guidance (PUrDeG) model for cultural heritage sites, which was developed as part of a research project. We explain how we used various techniques to engage various actors in preparing urban design guidelines for a cultural heritage site. In addition, the article discusses the importance of community engagement techniques and processes in developing urban design guidance, and the context of guidelines for sustainable conservation of cultural heritage sites with examples from the United Kingdom and Turkey. It then presents a case study conducted in the Hanlar District, a Unesco world heritage site in Bursa, Turkey. The case study includes research on planning decisions, site analysis, a survey of urban residents, in depth interviews with local artisans, and an urban design workshop with various actors. The main outcomes of this study include a presentation of how to use various community engagement techniques to prepare urban design guidelines for cultural heritage sites in Turkey, an urban design guidance system for Bursa, and a list of recommendations related to urban design guidelines for the Hanlar District and Bursa in the light of UK experience.

scholarly journals Open source timed pressure control hardware and software for delivery of air mediated distensions in animal models

2021 ◽  
Author(s):  
Trishna Patel ◽  
Jamie Hendren ◽  
Nathan Lee ◽  
Aaron D Mickle
Keyword(s):  
Open Source ◽  
Graphical User Interface ◽  
Low Cost ◽  
Pressure Control ◽  
Solenoid Valve ◽  
Relative Ease ◽  
Bladder Distension ◽  
Data Acquisition Software ◽  
Number Of Cycles ◽  
Stimulation Of

AbstractStudying the visceral sensory component of peripheral nervous systems can be challenging due to limited options for consistent and controlled stimulation. One method for mechanical stimulation of hollow organs, including colon and bladder, are controlled distensions mediated by compressed air. For example, distension of the bladder can be used as an assay for bladder nociception. Bladder distension causes a corresponding increase in abdominal electromyography, which increases with distension pressure and is attenuated with analgesics. However, the hardware used to control these distensions are primarily all one-off custom builds, without clear directions how to build your own. This has made it difficult for these methods to be fully utilized and replicated as not everyone has access, knowledge and resources required to build this controller. Here we show an open-source Arduino based system for controlling a solenoid valve to deliver timed pressure distensions in the experimental model. This device can be controlled by one of two methods through direct TTL pulses from the experimenters data acquisition software (ex. CED Spike2) or by a graphical user interface, where the user can set the time before, during, and after distension as well as the number of cycles. This systems low cost and relative ease to build will allow more groups to utilize timed pressure distensions in their experiments.Specifications table

scholarly journals Towards a Living Lab for Enhanced Thermal Comfort and Air Quality: Analyses of Standard Occupancy, Weather Extremes, and COVID-19 Pandemic

2021 ◽  
Vol 9 ◽  
Author(s):  
Giulia Ulpiani ◽  
Negin Nazarian ◽  
Fuyu Zhang ◽  
Christopher J. Pettit
Keyword(s):  
Environmental Quality ◽  
Low Cost ◽  
Design Guidelines ◽  
Weather Extremes ◽  
Fine Grained ◽  
Occupancy Patterns ◽  
Living Lab ◽  
Spatial Coverage ◽  
Educational Buildings ◽  
Extreme Variability

Maintaining indoor environmental (IEQ) quality is a key priority in educational buildings. However, most studies rely on outdoor measurements or evaluate limited spatial coverage and time periods that focus on standard occupancy and environmental conditions which makes it hard to establish causality and resilience limits. To address this, a fine-grained, low-cost, multi-parameter IOT sensor network was deployed to fully depict the spatial heterogeneity and temporal variability of environmental quality in an educational building in Sydney. The building was particularly selected as it represents a multi-use university facility that relies on passive ventilation strategies, and therefore suitable for establishing a living lab for integrating innovative IoT sensing technologies. IEQ analyses focused on 15 months of measurements, spanning standard occupancy of the building as well as the Black Summer bushfires in 2019, and the COVID-19 lockdown. The role of room characteristics, room use, season, weather extremes, and occupancy levels were disclosed via statistical analysis including mutual information analysis of linear and non-linear correlations and used to generate site-specific re-design guidelines. Overall, we found that 1) passive ventilation systems based on manual interventions are most likely associated with sub-optimum environmental quality and extreme variability linked to occupancy patterns, 2) normally closed environments tend to get very unhealthy under periods of extreme pollution and intermittent/protracted disuse, 3) the elevation and floor level in addition to room use were found to be significant conditional variables in determining heat and pollutants accumulation, presumably due to the synergy between local sources and vertical transport mechanisms. Most IEQ inefficiencies and health threats could be likely mitigated by implementing automated controls and smart logics to maintain adequate cross ventilation, prioritizing building airtightness improvement, and appropriate filtration techniques. This study supports the need for continuous and capillary monitoring of different occupied spaces in educational buildings to compensate for less perceivable threats, identify the room for improvement, and move towards healthy and future-proof learning environments.

Engineering Design Guidelines, Drawings and Specifications for Support Engineering of Suppressive Shields.

1976 ◽  
Author(s):  
F. J. Schroeder ◽  
R. L. Kachinski ◽  
R. W. Schnepfe ◽  
D. M. Koger ◽  
James L. McKivrigan
Keyword(s):  
Engineering Design ◽  
Design Guidelines ◽  
Support Engineering

Low-Water Stream Crossings: The Iowa Experience

2003 ◽  
Vol 1819 (1) ◽  
pp. 355-361 ◽  
Author(s):  
R. R. Gu ◽  
T. J. McDonald ◽  
R. A. Lohnes
Keyword(s):  
Material Selection ◽  
Low Cost ◽  
Geographic Region ◽  
Design Guidelines ◽  
Warning Signs ◽  
Water Stream ◽  
Safe Alternative ◽  
Low Volume Roads ◽  
State And Local ◽  
Selection Of

Replacement of old, unsafe bridges on low-volume roads is an increasing concern in rural America. Counties and local jurisdictions with inadequate bridges on secondary roads are faced with large capital expenditures for replacement structures or possible road closings. Low-water stream crossings (LWSCs) can provide a low-cost and reasonably safe alternative. Three types of LWSC are unvented fords, vented fords, and low-water bridges. A study was conducted to develop design guidelines for all three types of LWSC. Although the study focused on Iowa, the results are thought to be applicable to a wider geographic region. The salient features of this design process, including site selection, selection of most effective LWSC type, and geometric and material selection design, are described for the three types of structures. Although potential legal liability associated with LWSCs is a concern, the Iowa experience indicates that, with adequate warning signs, accidents and subsequent tort claims may actually be less with LWSCs than with deficient and obsolete bridges. On the basis of this history, it appears that potential liability from the use of prudently designed LWSCs is not a high risk. However, each state and local agency should thoroughly study code and local ordinance restrictions when considering LWSC options.

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