ELASTOMERIC POLYMERS FOR BLAST AND BALLISTIC RETROFITTING OF STRUCTURES

2015 ◽  
Vol 76 (1) ◽  
Author(s):  
H. M. C. C. Somarathna ◽  
S. N. Raman ◽  
A. A. Mutalib ◽  
K. H. Badri
Keyword(s):  
Critical Infrastructures ◽  
Structural Systems ◽  
Impact Loads ◽  
Structural Elements ◽  
Major Threat ◽  
Novel Approach ◽  
New Development ◽  
The World

In many parts of the world, terrorism has become a major threat to nations, and terrorist activities and accidental explosions have been directed towards the destruction of buildings and critical infrastructures. As a result, almost every new development requires the consideration of safety and security aspects such that even a new building incorporates protective engineering features in its design. In this aspect, researchers have been investigating the use of elastomeric polymers (such as polyurethane and polyurea) for structural retrofitting applications due to attractive characteristics and morphology exhibited by these materials. This paper provides a review on this novel approach of strengthening structural elements and systems to enhance their capacity against blast and ballistic threats. The discussions in this review have been focussed on the application of this technique on the most widely used structural systems of masonry, concrete, metallic and composite structural systems. This technique offers an alternative to existing strengthening techniques in protecting structures against the risks of blast, ballistic and impact loads.  

BIM-based energy consumption assessment of the on-site construction of building structural systems

2019 ◽  
Vol 9 (1) ◽  
pp. 2-14 ◽  
Author(s):  
Hao Zhou ◽  
Ehsan Rezazadeh Azar
Keyword(s):  
Energy Consumption ◽  
Environmental Assessment ◽  
Carbon Emissions ◽  
Assessment Tool ◽  
Information Modeling ◽  
Structural Systems ◽  
Structural Elements ◽  
Structural System ◽  
Content Type ◽  
Novel Approach

Purpose Steel and reinforced concrete are among the most common structural materials used in the construction industry. Cost and the speed of construction have been usually the main criteria when selecting a building’s structural system, whereby the environmental impact of the structural material is sometimes ignored. Availability of an easy-to-use tool for environmental assessment of the structural alternatives could encourage this evaluation in the decision making. The purpose of this paper is to introduce an automated tool for the environmental assessment of the on-site construction processes of a building structural system, which calculates the energy consumption and carbon emissions of the structural system as a parameter for comparison. Design/methodology/approach This assessment tool is implemented using a building information modeling (BIM) platform to extract structural elements and their key attributes, such as type, geometrical and locational data. These data are processed together with a productivity database to calculate machine hours, and then predefined energy and carbon inventories are used to assess the energy consumption of the structural system in the erection/installation stage. Findings This assessment tool provides an automated and easy-to-use approach to estimate energy consumption and carbon emissions of different structural systems that are modeled in a BIM platform. The results of this tool were within the ranges reported by the available studies. Originality/value This research project presents a novel approach to use BIM-based attributes of the structural elements to calculate the required efforts, i.e. machine hours, and assess their energy consumption and carbon emissions during construction processes.

scholarly journals Parametric Analysis of the Shear Lag Effect in Tube Structural Systems of Tall Buildings

2020 ◽  
Vol 11 (1) ◽  
pp. 278
Author(s):  
Ivan Hafner ◽  
Anđelko Vlašić ◽  
Tomislav Kišiček ◽  
Tvrtko Renić
Keyword(s):  
Parametric Analysis ◽  
Numerical Models ◽  
Tall Buildings ◽  
Structural Systems ◽  
Structural Elements ◽  
Structural System ◽  
Shear Lag ◽  
Shear Lag Effect ◽  
Lag Effect ◽  
Secondary Structural Elements

Horizontal loads such as earthquake and wind are considered dominant loads for the design of tall buildings. One of the most efficient structural systems in this regard is the tube structural system. Even though such systems have a high resistance when it comes to horizontal loads, the shear lag effect that is characterized by an incomplete and uneven activation of vertical elements may cause a series of problems such as the deformation of internal panels and secondary structural elements, which cumulatively grow with the height of the building. In this paper, the shear lag effect in a typical tube structure will be observed and analyzed on a series of different numerical models. A parametric analysis will be conducted with a great number of variations in the structural elements and building layout, for the purpose of giving recommendations for an optimal design of a tube structural system.

scholarly journals Interpreting Locked Photographic Data: The Case of Apollo 17 Photo GPN-2000-00113

Designs ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 8
Author(s):  
Pyrrhon Amathes ◽  
Paul Christodoulides
Keyword(s):  
Experimental Data ◽  
Computer Simulations ◽  
The Moon ◽  
Geometrical Analysis ◽  
Apparent Position ◽  
Apollo Program ◽  
The Earth ◽  
Novel Approach ◽  
The World ◽  
The Moment

Photography can be used for pleasure and art but can also be used in many disciplines of science, because it captures the details of the moment and can serve as a proving tool due to the information it preserves. During the period of the Apollo program (1969 to 1972), the National Aeronautics and Space Administration (NASA) successfully landed humans on the Moon and showed hundreds of photos to the world presenting the travel and landings. This paper uses computer simulations and geometry to examine the authenticity of one such photo, namely Apollo 17 photo GPN-2000-00113. In addition, a novel approach is employed by creating an experimental scene to illustrate details and provide measurements. The crucial factors on which the geometrical analysis relies are locked in the photograph and are: (a) the apparent position of the Earth relative to the illustrated flag and (b) the point to which the shadow of the astronaut taking the photo reaches, in relation to the flagpole. The analysis and experimental data show geometrical and time mismatches, proving that the photo is a composite.

scholarly journals Informed consent and informed intervention: SARS-CoV-2 vaccinations not just call for disclosure of newly emerging safety data but also for hypothesis generation and testing

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Johannes C. Fischer ◽  
Albrecht G. Schmidt ◽  
Edwin Bölke ◽  
Verena Keitel ◽  
Torsten Feldt ◽  
...  
Keyword(s):  
Health Care ◽  
Health Care Providers ◽  
Viral Infections ◽  
Safety Data ◽  
Hypothesis Generation ◽  
Care Providers ◽  
Vaccination Programs ◽  
Major Threat ◽  
The World ◽  
Population Scale

Abstract Background COVID-19 infection is a major threat to patients and health care providers around the world. One solution is the vaccination against SARS-CoV-2. Methods We performed a comprehensive query of the latest publications on the prevention of viral infections including the recent vaccination program and its side effects. Results The situation is evolving rapidly and there is no reasonable alternative to population-scale vaccination programs as currently enrolled. Conclusion Therefore, regulatory authorities should consider supplementing their conventional mandate of post-approval pharmacovigilance, which is based on the collection, assessment, and regulatory response to emerging safety findings.

Improved Identification of Portraiture of the Julio-Claudian Period with Mobile Apps

2021 ◽  
Author(s):  
Dmitri A. Gusev
Keyword(s):  
Image Analysis ◽  
Cultural Heritage ◽  
Mobile Apps ◽  
Multiple Views ◽  
Novel Approach ◽  
The World ◽  
Mobile Imaging ◽  
Private Collections ◽  
Historical Periods

We present the results of our image analysis of portrait art from the Roman Empire’s Julio-Claudian dynastic period. Our novel approach involves processing pictures of ancient statues, cameos, altar friezes, bas-reliefs, frescoes, and coins using modern mobile apps, such as Reface and FaceApp, to improve identification of the historical subjects depicted. In particular, we have discovered that the Reface app has limited, but useful capability to restore the approximate appearance of damaged noses of the statues. We confirm many traditional identifications, propose a few identification corrections for items located in museums and private collections around the world, and discuss the advantages and limitations of our approach. For example, Reface may make aquiline noses appear wider or shorter than they should be. This deficiency can be partially corrected if multiple views are available. We demonstrate that our approach can be extended to analyze portraiture from other cultures and historical periods. The article is intended for a broad section of the readers interested in how the modern AI-based solutions for mobile imaging merge with humanities to help improve our understanding of the modern civilization’s ancient past and increase appreciation of our diverse cultural heritage.

Design of a Remarkable Bascule Bridge Over an Historical Canal

2019 ◽  
Author(s):  
Benoit Cusson ◽  
Tony Mailhot
Keyword(s):  
Steel Structure ◽  
City Centre ◽  
Critical Infrastructures ◽  
Historic Site ◽  
The World ◽  
Hydraulic Cylinders ◽  
The City ◽  
Movable Bridge

<p>The Gouin bascule bridge is a 1,300 tons gigantic steel structure that allows pleasure boats to enter the Chambly Canal National Historic Site and provides access over the Richelieu river for vehicles, cyclists and pedestrians. As part of a project to revitalize and modernize the city centre, the architectural concept of the movable bridge will provide a landmark to this highly touristic site. There are only few examples in the world of such movable bridges with a large suspended counterweight. The challenges of the project include strict architectural criteria, fabrication and alignment of over 800 mm in diameter pins, the assembly on-site of remarkably large bridge parts and the precise balancing of the bridge.</p><p>When designing this structure, WSP made sure to consider the non-redundant aspect of some parts of the structure. Details regarding the design of the stays supporting the entire upper structure and the hydraulic cylinders initiating the rotation are described in this paper. The planning of the works in the middle of the critical infrastructures and services surrounding the bridge is explained. Since no interruption of the navigation on the canal was allowed during construction, some special considerations had to be taken with regards to the works at the foundation units.</p>

scholarly journals Serviceability and post-failure behaviour of laminated glass structural elements

2019 ◽  
Author(s):  
Lorenzo Ruggero Piscitelli
Keyword(s):  
Engineering Design ◽  
Structural Design ◽  
Laminated Glass ◽  
Structural Elements ◽  
Failure Behaviour ◽  
Multi Scale ◽  
Synthetic Materials ◽  
Cold Bending ◽  
The World ◽  
Safety Assessments

Glass structures are being built ever more frequently all over the world, in a growing architectural trend towards light, transparency and sustainability. The engineering design of laminated glass elements being profoundly influenced by properties of interlayers, this multi-scale research highlights some among the key elements on the hyperelastic and viscoplastic response of such synthetic materials. Results and new discoveries are interpreted to better model and predict the response of laminated glass structures: examples are provided for design applications to post-failure safety assessments, structural design and cold-bending techniques. Still, in a vastly unknown field, a growing market and foggy regulatory framework, many challenges and research opportunities remain to be dealt with.

scholarly journals Evaluation of Salt-water Intrusion in the Coastal Area of Igbokoda, Southwestern Nigeria

2018 ◽  
Vol 6 (01) ◽  
Author(s):  
Talabi A. O ◽  
Ajayi C. A ◽  
Afolagboye L. O ◽  
Oyedele A. A ◽  
Ojo O. F ◽  
...  
Keyword(s):  
Coastal Area ◽  
Salt Water ◽  
Silty Sand ◽  
High Resistivity ◽  
Salt Water Intrusion ◽  
Southwestern Nigeria ◽  
Major Threat ◽  
Sandy Clay ◽  
The World ◽  
Electrical Sounding

Saltwater intrusion into the coastal aquifer has long been recognized as a major threat to groundwater quality around the world. Groundwater evaluation of salt water intrusions in Igbokoda coastal area, southwestern Nigeria was carried out employing combined Horizontal Profiling and Vertical electrical sounding. Two traverses each with two sounding points were occupied. The result from the survey revealed 4 to 5 major layers comprising the unconsolidated silty sand and sandy clay (overburden), clayey zone, consolidated sand zone, partly intruded salt water intruded sandy clay zone and salt water intruded clay zone. The curves were the complex types KQH, KHA, QH and HKH curves. The overburden has resistivity that ranged from 253 to 1316.7Ω-m, thickness that ranged from 0.2 m to 7m. The clayey zone had resistivity of 846.0 Ω-m and thickness of 4m. The consolidated sand zone had resistivity that ranged from 2848.7 to 2865.7Ω-m and thickness that ranged between 4 and 21m. The partly intruded salt water zone is characterized by resistivity that varies between 18.4Ω-m and 93.0Ω-m and thickness of about 7-25m. The salt water intruded zone is characterized by resistivity that ranges between 4.1Ω-m and 9.7Ω-m and thickness of 4-48m. The partly-salt water intruded zones and salt water intruded zone were characterized with low resistivity while the high resistivity zones of consolidated sand layer constitute fresh water bearing zone that could serve as boreholes in the study area.

scholarly journals A global assessment of the potential distribution of naturalized and planted populations of the ornamental alien tree Schinus molle

NeoBiota ◽  
2021 ◽  
Vol 68 ◽  
pp. 105-126
Author(s):  
Jorge E. Ramírez-Albores ◽  
David M. Richardson ◽  
Valdir M. Stefenon ◽  
Gustavo A. Bizama ◽  
Marlín Pérez-Suárez ◽  
...  
Keyword(s):  
South Africa ◽  
Potential Distribution ◽  
Natural Populations ◽  
High Survival ◽  
Ecological Processes ◽  
Coverage Area ◽  
Schinus Molle ◽  
Novel Approach ◽  
The World ◽  
Dry Climates

The Peruvian Peppertree (Schinus molle L.) is an evergreen tree native to semiarid environments of Peru and Bolivia in South America. This tree has been introduced and widely planted for ornamental and forestry purposes in several semiarid regions of the world because its seedlings are easily established and have a high survival rate; it also grows quickly, and it is tolerant of dry climates. We compared the global and regional niches of naturalized and planted populations of S. molle in order to examine the invasive stages and potential distribution of this species in four regions of the world. This work provides a novel approach for understanding the invasion dynamics of S. molle in these areas and elucidates the ecological processes that bring about such invasions. Most naturalized and planted populations were found to be in equilibrium with the environment. In its native range as well as in Australia and South Africa the models of the coverage area of habitat suitability for natural populations were the highest, whereas the coverage area of planted populations was lower. For planted populations in Australia and South Africa, a large percentage of predicted presences fell within sink populations. The invasion stages of S. molle vary across regions in its adventive range; this result may be attributable to residence time as well as climatic and anthropic factors that have contributed to the spread of populations.

Sign in / Sign up

Export Citation Format

Share Document