Utilisation d'éléments structuraux en aluminium dans les ponts routiers : Étude économique et structurale

The study presented in this paper is part of a project aiming at evaluating the potential use of aluminum in structures. The types of intervention could range from a simple repair or a reinforcement involving structural aluminum, the replacement of a used bridge deck by an aluminum deck, to the construction of a new bridge made in full or in part of aluminum. It is this latter type of intervention that justified a research project, the results of which are presented in this article. The first step involves identifying the most advantageous type of aluminum structural system from a structural standpoint as well as an economic standpoint. This step includes the analysis and partial design of 40 girder- or truss-type road bridges, spanning 15 and 35 m, supporting either an active concrete slab or an aluminum deck. These studies have shown that bridges built using a Pratt-type truss and an active concrete slab provided the best results. It is also shown that some calculation criteria, such as vibration, deflection, and fatigue criteria limited the extensive use of aluminum in bridges. In the second step, nine bridges are more comprehensively analysed and designed, based on the standards used in North America, and three are fully designed, including the connexions, in order to realize a cost analysis study that is as accurate as possible. Special attention is given to vibration and fatigue problems as well as to the details related to connexions calculation. The study concludes that the development of an aluminum-only medium span road bridge system is a non-viable project in the short to mid term from a structural standpoint as well as an economic standpoint, and it makes recommendations on the use of aluminum decks and on the continuation of the work.Key words: aluminum, analysis, bridges, connexions, design, fatigue, standards, vibration.[Journal translation]

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Design and Implementation of a Hospital-based Trauma Surveillance Registry in a Resource-Poor Setting: A Cost Analysis Study

Injury ◽

10.1016/j.injury.2020.04.044 ◽

2020 ◽

Vol 51 (7) ◽

pp. 1548-1553

Author(s):

Laura N. Purcell ◽

Emily Nip ◽

Jared Gallaher ◽

Carlos Varela ◽

Yotamu Gondwe ◽

...

Keyword(s):

Cost Analysis ◽

Resource Poor Setting ◽

Analysis Study ◽

Design And Implementation ◽

Resource Poor

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Cost-analysis study of second generation antihistamines used in the treatment of allergic rhinitis in India

International Journal of Basic & Clinical Pharmacology ◽

10.18203/2319-2003.ijbcp20162218 ◽

2016 ◽

pp. 1228-1233

Author(s):

Amandeep Singh ◽

Hitender Kumar

Keyword(s):

Allergic Rhinitis ◽

Cost Analysis ◽

Second Generation ◽

Analysis Study

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U/sub 3/O/sub 8/ production cost analysis study. [CASHFLOW]

10.2172/6228407 ◽

1978 ◽

Keyword(s):

Cost Analysis ◽

Production Cost ◽

Analysis Study

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Experimental and theoretical investigation of composite truss beams

MATEC Web of Conferences ◽

10.1051/matecconf/201817404001 ◽

2018 ◽

Vol 174 ◽

pp. 04001

Author(s):

Jan Bujnak ◽

Peter Michalek ◽

Wieslaw Baran

Keyword(s):

Concrete Slab ◽

Longitudinal Shear ◽

Finite Element Analyses ◽

Structural System ◽

Local Effects ◽

Relative Slip ◽

Shear Connectors ◽

Design Specifications ◽

Bridge Structures ◽

European Standards

The design specifications of composite trusses are only partially included in the European standards. However this construction system can be considered as one of the most economical for building and bridge structures. To create an interaction between steel and concrete, it is necessary to prevent the relative slip at the steel and concrete interface using the shear connectors. But the local effects of a concentrated longitudinal shear force between steel truss chord and concrete slab, as special task, should be appropriately examined. The finite element analyses can be used to investigate numerically this structural system behaviour, exploiting several computer procedures. The experimental research has tested these procedures. The outputs of this study are presented in the paper.

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Thermal efficiency and cost analysis of solar water heater made in Rwanda

Energy Exploration & Exploitation ◽

10.1177/0144598718815240 ◽

2018 ◽

Vol 37 (3) ◽

pp. 1147-1161 ◽

Cited By ~ 1

Author(s):

Esdras Nshimyumuremyi ◽

Wang Junqi

Keyword(s):

Cost Analysis ◽

Thermal Efficiency ◽

Solar Water Heater ◽

Water Heating ◽

Water Heater ◽

Solar Water Heating ◽

Solar Water ◽

Water Heaters ◽

Solar Water Heaters ◽

Made In

Solar water heating is a technology of capturing the energy from the sun's radiation for the purpose of raising the temperature of water from water supply temperature to the desired higher temperature depending on the use. There are many views and discussions on the questions of thermal efficiency of solar water heaters and their associated cost, especially different customers/users want to replace their existing conventional water heating energy by solar water heating systems. In this present paper, a deep investigation has been accomplished to determine thermal efficiency and cost analysis of solar water heater made in Rwanda. During manufacturing of solar water heater, the collector was the main part to emphasize on. The high efficiency of the system was achieved by replacing galvanized iron sheet by aluminum sheet slotted and black painted as an absorber plate. The ambient temperature and average solar radiation of the three sites where solar water heaters are installed were investigated. The used materials, specifications and sizing were discussed in this paper.

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Almost Exact Computation of Eigenvalues in Approximate Differential Problems

Mathematical and Computational Applications ◽

10.3390/mca24040096 ◽

2019 ◽

Vol 24 (4) ◽

pp. 96 ◽

Cited By ~ 1

Author(s):

José M. A. Matos ◽

Maria João Rodrigues

Keyword(s):

Eigenvalue Problems ◽

High Accuracy ◽

Second Step ◽

Matlab Toolbox ◽

Differential Problem ◽

Algebraic Problem ◽

Polynomial Expression ◽

Computation Of Eigenvalues ◽

Potential Use ◽

Mathematics And Physics

Differential eigenvalue problems arise in many fields of Mathematics and Physics, often arriving, as auxiliary problems, when solving partial differential equations. In this work, we present a method for eigenvalues computation following the Tau method philosophy and using Tau Toolbox tools. This Matlab toolbox was recently presented and here we explore its potential use and suitability for this problem. The first step is to translate the eigenvalue differential problem into an algebraic approximated eigenvalues problem. In a second step, making use of symbolic computations, we arrive at the exact polynomial expression of the determinant of the algebraic problem matrix, allowing us to get high accuracy approximations of differential eigenvalues.

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miRNAs as Biomarkers in Disease: Latest Findings Regarding Their Role in Diagnosis and Prognosis

Cells ◽

10.3390/cells9020276 ◽

2020 ◽

Vol 9 (2) ◽

pp. 276 ◽

Cited By ~ 39

Author(s):

Carmen Elena Condrat ◽

Dana Claudia Thompson ◽

Madalina Gabriela Barbu ◽

Oana Larisa Bugnar ◽

Andreea Boboc ◽

...

Keyword(s):

High Specificity ◽

Research Field ◽

Therapeutic Interventions ◽

Protein Levels ◽

Diagnosis And Prognosis ◽

Specificity And Sensitivity ◽

Online Databases ◽

Patient Profiles ◽

Potential Use ◽

Made In

MicroRNAs (miRNAs) represent a class of small, non-coding RNAs with the main roles of regulating mRNA through its degradation and adjusting protein levels. In recent years, extraordinary progress has been made in terms of identifying the origin and exact functions of miRNA, focusing on their potential use in both the research and the clinical field. This review aims at improving the current understanding of these molecules and their applicability in the medical field. A thorough analysis of the literature consulting resources available in online databases such as NCBI, PubMed, Medline, ScienceDirect, and UpToDate was performed. There is promising evidence that in spite of the lack of standardized protocols regarding the use of miRNAs in current clinical practice, they constitute a reliable tool for future use. These molecules meet most of the required criteria for being an ideal biomarker, such as accessibility, high specificity, and sensitivity. Despite present limitations, miRNAs as biomarkers for various conditions remain an impressive research field. As current techniques evolve, we anticipate that miRNAs will become a routine approach in the development of personalized patient profiles, thus permitting more specific therapeutic interventions.

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Review of Research on the Seismic Behavior of Integral Prefabricated Prestressed Concrete Slab-Column Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.831.176 ◽

2013 ◽

Vol 831 ◽

pp. 176-180 ◽

Cited By ~ 1

Author(s):

Li Li Wu ◽

Ya Can Cui ◽

Rong Bin Zhou ◽

Jia Qing Shi ◽

Peng He ◽

...

Keyword(s):

Research Methods ◽

Seismic Performance ◽

Prestressed Concrete ◽

Seismic Behavior ◽

Concrete Slab ◽

Research Priorities ◽

Structural System ◽

Column Structure

The integral prefabricated prestressed concrete slab-column structure was a new structural system introduced to China in 1980s. The structure has a series of obvious advantages and the scholars focus research priorities on its seismic performance. The research methods and developments of seismic behavior of the slab-column structure are summarized, and some measures are also put forward to improve the seismic behavior.

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