Assessing and mitigating risks to bridges from large wood using satellite imagery

2022 ◽  
pp. 1-21
Author(s):  
D. Panici ◽  
P. Kripakaran
Keyword(s):  
At Risk ◽  
Satellite Imagery ◽  
Structural Integrity ◽  
Rapid Assessment ◽  
Mitigation Measures ◽  
Bridge Structure ◽  
Large Wood ◽  
Impact Forces ◽  
Significant Damage ◽  
The Impact

The transport and accumulation of floating large wood (LW) debris at bridges can pose a major risk to their structural integrity. The impact forces arising from collisions of LW can cause significant damage to piers, and accumulations can constrict the flow and exacerbate scour at piers and abutments. Furthermore, LW accumulations increase afflux upstream of bridges, heightening flood risk for adjoining areas. Consequently, there is a need for a practical and rapid approach to identify bridges prone to LW-related hazards and to prevent the formation of LW accumulations. This paper proposes an approach based on satellite imagery to (i) quantify the risk of LW at a bridge structure and (ii) locate a LW-trapping system upstream of the identified vulnerable bridges to dramatically reduce risks of LW-related damage. This methodology is applied to major rivers in Devon (UK). 26 bridges were identified as at risk to LW with the majority prone to LW jams. Furthermore, satellite imagery was used to identify 12 locations for the potential installation of LW trapping systems for bridge protection. The results reported in this paper show that satellite imagery is a powerful tool for the rapid assessment and plan of mitigation measures for bridges at risk to LW.

scholarly journals Brief communication: Rapid assessment of damaged residential buildings in the Florida Keys after Hurricane Irma

2018 ◽  
Vol 18 (7) ◽  
pp. 2041-2045 ◽  
Author(s):  
Siyuan Xian ◽  
Kairui Feng ◽  
Ning Lin ◽  
Reza Marsooli ◽  
Daniel Chavas ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Storm Surge ◽  
Satellite Imagery ◽  
Residential Buildings ◽  
Rapid Assessment ◽  
Florida Keys ◽  
Damage Survey ◽  
Complete Destruction ◽  
Significant Damage ◽  
Hurricane Irma

Abstract. On 10 September 2017, Hurricane Irma made landfall in the Florida Keys and caused significant damage. Informed by hydrodynamic storm surge and wave modeling and post-storm satellite imagery, a rapid damage survey was soon conducted for 1600+ residential buildings in Big Pine Key and Marathon. Damage categorizations and statistical analysis reveal distinct factors governing damage at these two locations. The distance from the coast is significant for the damage in Big Pine Key, as severely damaged buildings were located near narrow waterways connected to the ocean. Building type and size are critical in Marathon, highlighted by the near-complete destruction of trailer communities there. These observations raise issues of affordability and equity that need consideration in damage recovery and rebuilding for resilience.

Effects of Coupler Height Mismatch on Tank Car Stub Sills

2000 ◽  
Author(s):  
Anand Prabhakaran ◽  
Vinaya Sharma ◽  
Jose S. Peña
Keyword(s):  
Structural Integrity ◽  
Longitudinal Force ◽  
Operating Conditions ◽  
Vertical Force ◽  
Static Tests ◽  
Critical Areas ◽  
Significant Damage ◽  
Load Tests ◽  
Static Conditions ◽  
The Impact

Abstract Revenue service tests of tank cars conducted by the Association of American Railroads (AAR) as part of the ‘Freight Equipment Environmental Sampling Tests’ (FEEST) program have measured high coupler vertical loads. It is believed that such high vertical loads can cause significant damage to the structural integrity of tank car stubsills, thereby seriously affecting operational safety. Also, it is suspected that coupler height mismatches are a major source of these vertical forces, and thereby contribute to stubsill failures. The focus of this paper is the study of the effect of coupler height mismatches on stub sill integrity. As part of this study a tank car loaded to 266,200 lb. was instrumented and tested, in static conditions and during impact. The static tests consisted of a series of longitudinal load (squeeze) tests conducted at three different coupler heights, and vertical load tests with forces being applied at the coupler shank. The impact tests consisted of a series of impacts at speeds ranging from 2 mph to 8.5 mph for the following coupler mismatch levels: a) Struck and striking car at the same level, b) Struck car 2″ higher, and c) Struck car 2″ lower. In addition to the testing, finite element models were developed to help in studying additional operating conditions. These models were validated using the test results. The results from the testing indicate that coupler height mismatches have a significant effect on the vertical force levels and the stress levels seen at critical car locations. The stresses in critical areas are generally higher when the struck car is lower. Differences over 50% (compared to when the cars are level) were noted at the head brace, when the struck car was 2″ lower than the hammer car. The tests also established the criticality of vertical forces on the structural integrity of the stubsill. On average, a 50,000 lb. vertical force can generate as much stress as a 680,000 lb. longitudinal force. This work is being funded by the Office of Research & Development of the Federal Railroad Administration (FRA).

scholarly journals Rapid Assessment of Damaged Homes in the Florida Keys after Hurricane Irma

2018 ◽  
Author(s):  
Siyuan Xian ◽  
Kairui Feng ◽  
Ning Lin ◽  
Reza Marsooli ◽  
Dan Chavas ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Storm Surge ◽  
Satellite Imagery ◽  
Residential Buildings ◽  
Rapid Assessment ◽  
Florida Keys ◽  
Damage Survey ◽  
Complete Destruction ◽  
Significant Damage ◽  
Hurricane Irma

Abstract. On September 10, 2017, Hurricane Irma made landfall in the Florida Keys and caused significant damage. Informed by hydrodynamic storm surge and wave modeling and post-storm satellite imagery, a rapid damage survey was soon conducted for 1600+ residential buildings in Big Pine Key and Marathon. Damage categorizations and statistical analysis reveal distinct factors governing damage at these two locations. The distance from the coast is significant for the damage in Big Pine Key, as severely damaged buildings were located near narrow waterways connected to the ocean. Building type and size are critical in Marathon, highlighted by the near-complete destruction of trailer communities there. These observations raise issues of affordability and equity that need consideration in damage recovery and rebuilding for resilience.

Tangguh Project: In-Service Buckling Design of Offshore Pipelines With Major Uncertainties on Soil Characterization and Seabed Mobility

2021 ◽  
Author(s):  
Sabrina Bughi ◽  
Luigi Foschi ◽  
Lorenzo Marchionni ◽  
Roberta Vichi ◽  
Yansa Zulkarnain
Keyword(s):  
Structural Integrity ◽  
Mitigation Measures ◽  
Soil Characterization ◽  
Operating Life ◽  
Lateral Buckling ◽  
Natural Sand ◽  
Pull Out ◽  
Pipeline Route ◽  
The Impact ◽  
Soil Pipe

Abstract This paper is based on the experience made during the design and installation of an offshore pipeline recently completed in Indonesia, where a 24” subsea production pipeline (16km long in 70m water depth) was found susceptible during design to lateral buckling. Buckling is a well understood phenomenon. However, this project was characterized by major uncertainties mainly driven by soil characterization, soil zonation, soil-pipe interaction, seabed mobility and seabed liquefaction. These uncertainties have played a key role in the in-service buckling design. In particular, extreme pipeline embedment scenarios ranging from fully exposed to fully covered (due to natural sand transportation) were accounted with a significant impact on soil-pipe interaction. To limit the development of excessive strain within the acceptance criteria, a mitigation strategy based on interacting planned buckles has been adopted installing three Buckle Initiators (BI) along the pipeline route. During design great efforts have been spent with the aim to demonstrate the robustness of the proposed solution. 3-D FEM simulations with ABAQUS have been performed taking into account the pipeline route including route curves and the sea bottom profile and the buckle initiators with their main geometries. All uncertainties have been considered following a deterministic approach. The impact of environmental and accidental loads due to a potential trawl-gear interaction were assessed as well. The pipeline susceptibility to lateral and/or upheaval buckling along the sandwave areas has been analyzed as well in order to evaluate the need of mitigation measures suitable to freeze the pipeline configuration during the operating life. Finally, once the lateral buckling design philosophy was established, the cyclic expansion and walking behavior of the pipeline were assessed to verify the pipeline structural integrity at buckles, route curve pull-out and the accumulative pipeline expansion at spools. This paper presents all main engineering aspects faced during design and first feedbacks from field after the pipeline installation.

The Impact of Insect Infestation on Stored Purpled Cocoa Beans

2018 ◽  
Vol 1 (3) ◽  
pp. 176-181 ◽  
Author(s):  
E. Tettey
Keyword(s):  
Weight Loss ◽  
Insect Population ◽  
Insect Infestation ◽  
Percentage Weight Loss ◽  
Cocoa Beans ◽  
Significant Damage ◽  
Percentage Weight ◽  
Fermentation Period ◽  
The Impact

Under-fermentation of cocoa beans produces purple beans. The fermentation period is 6 to 7 days but some cocoa farmersunder-ferment their cocoa beans leading to the development of purple cocoa beans. This study determined the impact of insectinfestation on stored purple cocoa beans. Wet cocoa beans were fermented for 1, 2, 3, 4 and 5 days to produce the purple beans.Ephestia cautella and Tribolium castaneum, both singly and in combination, were introduced into the cocoa beans and storedfor different (30, 60, 90 and 120 days) period. Insect population, percentage weight loss and the contaminants produced bythese insects were determined. Cocoa beans infested with E. cautella alone had the highest population of 297.0 ± 22.7. Beansfermented for 3 days had the lowest insect population both singly and in combination after 120 days of storage. The highestpercentage weight loss was recorded in cocoa beans fermented for one day (10.1 ± 1.87%) and 4 days (10.1 ± 8.74%). T.castaneum did not cause much damage to the cocoa beans but E. cautella alone caused significant damage to stored cocoabeans. Insect infestation and poor fermentation contribute significantly to the reduction in quality of cocoa beans.

Case study and event analysis for mitigation of unpredictable volcanic hazard

Impact ◽  
2020 ◽  
Vol 2020 (3) ◽  
pp. 26-28
Author(s):  
Tsukasa Ohba
Keyword(s):  
At Risk ◽  
Graduate School ◽  
Volcanic Hazard ◽  
Hazard Mitigation ◽  
Scientific Discipline ◽  
Mitigation Measures ◽  
Event Analysis ◽  
Traditional Methods ◽  
Risk Communities

Volcanology is an extremely important scientific discipline. Shedding light on how and why volcanoes erupt, how eruptions can be predicted and their impact on humans and the environment is crucial to public safety, economies and businesses. Understanding volcanoes means eruptions can be anticipated and at-risk communities can be forewarned, enabling them to implement mitigation measures. Professor Tsukasa Ohba is a scientist based at the Graduate School of International Resource Studies, Akita University, Japan, and specialises in volcanology and petrology. Ohba and his team are focusing on volcanic phenomena including: phreatic eruptions (a steam-driven eruption driven by the heat from magma interacting with water); lahar (volcanic mudflow); and monogenetic basalt eruptions (which consist of a group of small monogenetic volcanoes, each of which erupts only once). The researchers are working to understand the mechanisms of these phenomena using Petrology. Petrology is one of the traditional methods in volcanology but has not been applied to disastrous eruptions before. The teams research will contribute to volcanic hazard mitigation.

Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

2020 ◽  
Author(s):  
Lukman Olagoke ◽  
Ahmet E. Topcu
Keyword(s):  
Control Measure ◽  
Control Measures ◽  
World Health ◽  
Mitigation Measures ◽  
Effective Control ◽  
The World ◽  
Decision Making Processes ◽  
And Performance ◽  
Health Organization ◽  
The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

The Democratic Costs of Constitutionalization— The European Case

2017 ◽  
Author(s):  
Dieter Grimm
Keyword(s):  
At Risk ◽  
Economic Integration ◽  
Fundamental Rights ◽  
European Law ◽  
European Court ◽  
Political Implications ◽  
The Impact ◽  
The Relationship ◽  
The Eu

This chapter examines the democratic costs of constitutionalization by focusing on the European case. It first considers the interdependence of democracy and constitutionalism before discussing how constitutionalization can put democracy at risk. It then explores the tension between democracy and fundamental rights, the constitutionalization of the European treaties, and the European Court of Justice’s (ECJ) two separate judgments regarding the relationship between European law and national law. It also assesses the impact of the ECJ’s jurisprudence on democracy, especially in the area of economic integration. The chapter argues that the legitimacy problem the EU faces is caused in part by over-constitutionalization and that the remedy to this problem is re-politicization of decisions with significant political implications.

scholarly journals Potential and limitations of finite element modelling in assessing structural integrity of coralline algae under future global change

2015 ◽  
Vol 12 (19) ◽  
pp. 5871-5883 ◽  
Author(s):  
L. A. Melbourne ◽  
J. Griffin ◽  
D. N. Schmidt ◽  
E. J. Rayfield
Keyword(s):  
Climate Change ◽  
Finite Element ◽  
Structural Integrity ◽  
Geometric Model ◽  
Algal Growth ◽  
Coralline Algae ◽  
Rocky Shores ◽  
Element Analysis ◽  
Scan Data ◽  
The Impact

Abstract. Coralline algae are important habitat formers found on all rocky shores. While the impact of future ocean acidification on the physiological performance of the species has been well studied, little research has focused on potential changes in structural integrity in response to climate change. A previous study using 2-D Finite Element Analysis (FEA) suggested increased vulnerability to fracture (by wave action or boring) in algae grown under high CO2 conditions. To assess how realistically 2-D simplified models represent structural performance, a series of increasingly biologically accurate 3-D FE models that represent different aspects of coralline algal growth were developed. Simplified geometric 3-D models of the genus Lithothamnion were compared to models created from computed tomography (CT) scan data of the same genus. The biologically accurate model and the simplified geometric model representing individual cells had similar average stresses and stress distributions, emphasising the importance of the cell walls in dissipating the stress throughout the structure. In contrast models without the accurate representation of the cell geometry resulted in larger stress and strain results. Our more complex 3-D model reiterated the potential of climate change to diminish the structural integrity of the organism. This suggests that under future environmental conditions the weakening of the coralline algal skeleton along with increased external pressures (wave and bioerosion) may negatively influence the ability for coralline algae to maintain a habitat able to sustain high levels of biodiversity.

scholarly journals Evaluating Satellite Imagery‐Based Land Use Data for Describing Forestland Development in Western Washington

2009 ◽  
Vol 24 (4) ◽  
pp. 214-222 ◽  
Author(s):  
Jeffrey D. Kline ◽  
Alissa Moses ◽  
David Azuma ◽  
Andrew Gray
Keyword(s):  
Land Use ◽  
Satellite Imagery ◽  
Econometric Model ◽  
Landsat Imagery ◽  
Forest Inventory And Analysis ◽  
The Us ◽  
Western Washington ◽  
Us Census ◽  
The Impact ◽  
Density Development

Abstract Forestry professionals are concerned about how forestlands are affected by residential and other development. To address those concerns, researchers must find appropriate data with which to describe and evaluate rates and patterns of forestland development and the impact of development on the management of remaining forestlands. We examine land use data gathered from Landsat imagery for western Washington and evaluate its usefulness for characterizing low-density development of forestland. We evaluate the accuracy of the satellite imagery‐based land use classifications by comparing them with other data from US Forest Service's Forest Inventory and Analysis inventories and the US census. We then use the data to estimate an econometric model describing development as a function of socioeconomic and topographic factors and project future rates of development and forestland loss to 2020. We conclude by discussing how best to meet the land use data needs of researchers, forestry policymakers, and managers.

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