scholarly journals SUBGRID NUMERICAL MODELING OF TSUNAMI AND STORM SURGE INUNDATION IN A COASTAL URBAN SETTING

2020 ◽  
pp. 11
Author(s):  
Zhongduo Zhang ◽  
Nobuki Fukui ◽  
Yu Chida ◽  
Andrew Kennedy ◽  
Nobuhito Mori ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Storm Surge ◽  
Numerical Models ◽  
Shallow Water Equation ◽  
Physical Experiment ◽  
Urban Setting ◽  
Hazard Maps ◽  
Coastal City ◽  
The City ◽  
Shielding Effects

An experiment using a physical model of a coastal city was conducted to simulate tsunami and storm surge conditions which may lead to city inundation. The results of the physical experiment were compared with those from a subgrid numerical model based on the shallow water equation using the topography of the physical experiment obtained from LIDAR scanning. The experiment aims to provide a better understanding on the variation of tsunami or storm surge inundation level at different locations of the city due to the ground elevation, building arrangement, and shielding effects. The result from this experiment will serve to increase the accuracy of coastal numerical models and revise the current hazard maps and evacuation plans.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/k4v5EotRpfg

scholarly journals VULNERABILITY TO COASTAL FLOODING INDUCED BY TROPICAL CYCLONES

2011 ◽  
Vol 1 (32) ◽  
pp. 19 ◽  
Author(s):  
Gregorio Posada-Vanegas ◽  
Gerardo Durán-Valdez ◽  
Rodolfo Silva-Casarin ◽  
Maria Elena Maya-Magaña ◽  
Jose Antonio Salinas-Prieto
Keyword(s):  
Tropical Cyclones ◽  
Storm Surge ◽  
Natural Hazard ◽  
Numerical Models ◽  
Coastal Flooding ◽  
Return Periods ◽  
Hazard Maps ◽  
Flooding Hazard ◽  
Reduce Risk ◽  
2D Numerical Model

Hurricanes are a recurrent feature on Mexican coasts; they create floods whose economic and social damages are evident. The necessity to evaluate the natural hazard related to storm surge is fundamental to reduce risk in coastal areas. In order to generate flooding hazard maps, storm surge associated to different return periods is computed with a 2D numerical model. The first part of this work is related with the data and numerical models used to calculate the storm surge, the second part contain the results obtained with the simulations. This work has been done for the entire Mexican coastline but only results for the Gulf of Mexico are presented

San Francisco's Vision for the Future: An Integrated Urban Wastewater Management Plan

2009 ◽  
Vol 4 (1) ◽  
Author(s):  
Jonathan W. Loiacono ◽  
Chu-Fei H. Ho ◽  
Natalie V. Sierra ◽  
Domènec Jolis ◽  
Carolyn Chiu ◽  
...  
Keyword(s):  
San Francisco ◽  
Planning Process ◽  
Rainwater Harvesting ◽  
Control Plant ◽  
Management Plan ◽  
Urban Setting ◽  
Wastewater Management ◽  
Urban Watershed ◽  
Aging Infrastructure ◽  
The City

The City and County of San Francisco (“City”) embarked upon a 30-year master planning process in part prompted by public concerns related to the neighbourhood impacts of the Southeast Water Pollution Control Plant (SEP). The Sewer System Master Plan, as it is called, developed a long term Integrated Urban Watershed Management Plan for the City's treatment plants and collection system. This paper focuses on the planning framework and public input to the process, particularly as it relates to proposed changes to the SEP. The resulting improvements address issues of replacing aging infrastructure, eliminating odor emissions, and visually screening the treatment plants that are situated within an urban setting. The recommended project addresses the needed repair of the existing infrastructure; and proposes that the City move towards an integrated urban watershed approach, initially through localized rainwater harvesting and opportunistic water reclamation.

scholarly journals Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 458
Author(s):  
Drew C. Baird ◽  
Benjamin Abban ◽  
S. Michael Scurlock ◽  
Steven B. Abt ◽  
Christopher I. Thornton
Keyword(s):  
Numerical Modeling ◽  
Physical Model ◽  
Numerical Models ◽  
Hydraulic Performance ◽  
Physical Models ◽  
Protection Measures ◽  
Design Engineers ◽  
Model Study ◽  
Study Results ◽  
Wide Range

While there are a wide range of design recommendations for using rock vanes and bendway weirs as streambank protection measures, no comprehensive, standard approach is currently available for design engineers to evaluate their hydraulic performance before construction. This study investigates using 2D numerical modeling as an option for predicting the hydraulic performance of rock vane and bendway weir structure designs for streambank protection. We used the Sedimentation and River Hydraulics (SRH)-2D depth-averaged numerical model to simulate flows around rock vane and bendway weir installations that were previously examined as part of a physical model study and that had water surface elevation and velocity observations. Overall, SRH-2D predicted the same general flow patterns as the physical model, but over- and underpredicted the flow velocity in some areas. These over- and underpredictions could be primarily attributed to the assumption of negligible vertical velocities. Nonetheless, the point differences between the predicted and observed velocities generally ranged from 15 to 25%, with some exceptions. The results showed that 2D numerical models could provide adequate insight into the hydraulic performance of rock vanes and bendway weirs. Accordingly, design guidance and implications of the study results are presented for design engineers.

scholarly journals Numerical modeling of the hydraulic impact of riparian vegetation

2018 ◽  
Vol 44 ◽  
pp. 00194
Author(s):  
Krzysztof Wolski ◽  
Tomasz Tymiński ◽  
Grzegorz Chrobak
Keyword(s):  
Numerical Modeling ◽  
Riparian Vegetation ◽  
Water Surface ◽  
Numerical Models ◽  
Three Dimensional ◽  
Careful Examination ◽  
Impact Structure ◽  
Hydraulic Impact ◽  
Vegetation Zones ◽  
Maximal Shear Stress

This paper presents results of numerical modelling of riverbed segment with riparian vegetation performed with use of CCHE2 software. Vegetation zones are places where dynamic of water flow increases. Therefore, there is a need of careful examination of hydraulic impact structure of such zones. Accurate research is necessary and should be performed with use of physical or numerical models, two or three dimensional. Paper presents distribution of velocity and area of water surface for two variants of vegetation deposition acquired in CCHE2D software and modelled for riverbed with distinctive riparian vegetation. Results point to significant (30–40%) increase of maximal velocities in riverbed with riparian vegetation, while directly near the vegetation there were zones with very low velocities. Local damming occurs before vegetal zone. Maximal shear stress in zones with increased velocity is significantly augmented compared to conditions with no vegetation, which can cause more intensive erosion in those zones

scholarly journals Assessing storm surge hazard and impact of sea level rise in the Lesser Antilles case study of Martinique

2017 ◽  
Vol 17 (9) ◽  
pp. 1559-1571 ◽  
Author(s):  
Yann Krien ◽  
Bernard Dudon ◽  
Jean Roger ◽  
Gael Arnaud ◽  
Narcisse Zahibo
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Storm Surge ◽  
Numerical Models ◽  
Lesser Antilles ◽  
Adaptation Measures ◽  
Worst Case ◽  
Mitigation And Adaptation ◽  
The Impact

Abstract. In the Lesser Antilles, coastal inundations from hurricane-induced storm surges pose a great threat to lives, properties and ecosystems. Assessing current and future storm surge hazards with sufficient spatial resolution is of primary interest to help coastal planners and decision makers develop mitigation and adaptation measures. Here, we use wave–current numerical models and statistical methods to investigate worst case scenarios and 100-year surge levels for the case study of Martinique under present climate or considering a potential sea level rise. Results confirm that the wave setup plays a major role in the Lesser Antilles, where the narrow island shelf impedes the piling-up of large amounts of wind-driven water on the shoreline during extreme events. The radiation stress gradients thus contribute significantly to the total surge – up to 100 % in some cases. The nonlinear interactions of sea level rise (SLR) with bathymetry and topography are generally found to be relatively small in Martinique but can reach several tens of centimeters in low-lying areas where the inundation extent is strongly enhanced compared to present conditions. These findings further emphasize the importance of waves for developing operational storm surge warning systems in the Lesser Antilles and encourage caution when using static methods to assess the impact of sea level rise on storm surge hazard.

scholarly journals Numerical Modeling of a Punch Penetration Test Using the Discrete Element Method

2020 ◽  
Vol 28 (2) ◽  
pp. 1-7
Author(s):  
Rouhollah Basirat ◽  
Jafar Khademi Hamidi
Keyword(s):  
Numerical Modeling ◽  
Discrete Element Method ◽  
Numerical Models ◽  
Confining Pressure ◽  
Discrete Element ◽  
Numerical Results ◽  
Strength Parameter ◽  
Penetration Test ◽  
Strength Parameters ◽  
Element Method

AbstractUnderstanding the brittleness of rock has a crucial importance in rock engineering applications such as the mechanical excavation of rock. In this study, numerical modeling of a punch penetration test is performed using the Discrete Element Method (DEM). The Peak Strength Index (PSI) as a function of the brittleness index was calculated using the axial load and a penetration graph obtained from numerical models. In the first step, the numerical model was verified by experimental results. The results obtained from the numerical modeling showed a good agreement with those obtained from the experimental tests. The propagation path was also simulated using Voronoi meshing. The fracture was created under the indenter in the first step, and then radial fractures were propagated. The effects of confining pressure and strength parameters on the PSI were subsequently investigated. The numerical results showed that the PSI increases with enhancing the confining pressure and the strength parameter of the rock, including cohesion and the friction angle. A new relationship between the strength parameters and PSI was also introduced based on two variable regressions of the numerical results.

scholarly journals Numerical modeling of hiding properties of underwater acoUStic communication signals with linear sweep of the carrier

2020 ◽  
Author(s):  
К.Г. Кебкал
Keyword(s):  
Numerical Modeling ◽  
Continuous Spectrum ◽  
Gaussian Noise ◽  
Data Exchange ◽  
Numerical Models ◽  
Underwater Acoustic Communication ◽  
Underwater Acoustic ◽  
Communication Signals ◽  
Communication Signal ◽  
Spectrum Spread

На результатах численного моделирования продемонстрировано, что распределения вероятностей огибающей и фазы смеси гауссова шума и (слабого) гидроакустического сигнала связи, характеризуемого линейной разверткой несущей, могут иметь исчезающе малые отличия от аналогичных распределений, характерных для просто гауссова шума. Использование непрерывного расширения спектра сигнала связи может представлять интерес для задач скрытого обмена данными, в которых обнаружение сеанса связи устройствами перехвата должно быть затруднительным или невозможным. С применением численных моделей проанализированы возможности использования сигналов с непрерывным расширением спектра для скрытой цифровой гидроакустической связи посредством штатных приемоизлучающих гидроакустических систем, находящихся на вооружении действующих кораблей. Based on the results of the numerical modeling, the vanishingly small differences between the probability distributions of the envelope and phase of the sum of Gaussian noise and (weak) underwater acoustic signal with linear carrier sweep, and the same distributions for the Gaussian noise all alone are demonstrated. Utilization of the continuous spectrum spread of the communication signal may be applied to the task of covert data exchange, where detection of the communication session by the intercepting equipment must be complicated or impossible. Using numerical models, we analyzed the capabilities of implementation of the signals with continuous spectrum spread for covert digital underwater acoustic communications through the standard underwater acoustic transducers, which are in service on the operational ready vessels.

scholarly journals Student Homelessness: Sheltering Our Future: An Adaptable Approach to Underutilised City Spaces

2021 ◽  
Author(s):  
◽  
Caryl Ramos
Keyword(s):  
Urban Space ◽  
Modular Design ◽  
Well Being ◽  
Test Site ◽  
Urban Setting ◽  
Homeless Population ◽  
Future Application ◽  
Design Development ◽  
Urban Context ◽  
The City

<p>The increasing housing demands from population growth creates a persistent housing shortage and unaffordability in our cities. Students are one demographic that is dramatically affected as they move closer to their education provider for study. The student influx at the start of the semester creates a large demand in the already inadequate housing market. Students with a limited budget have reduced accommodation options and this consequently drives many into a state of homelessness. A study from University of Otago measures that over a quarter of New Zealand’s homeless population are students (Amore, 2016). This considerable number of students are living in cars, tents, couch-surfing and sleeping rough for weeks during their studies. The desperate situation impinges on the student’s health and well-being and thus their academic performance.  In this context, the scope of this research focuses on the requirements of homeless tertiary students in the urban setting. Their vulnerability, insecurity and distress are explored to provide direction to solutions that will alleviate the existing problems of their insufficient living environments. As proximity to the education providers and amenities are key factors, this thesis examines underutilised and leftover spaces within the city as opportunities for inhabitation, and to create efficient use of urban space. Currently, there are successful examples of activating overlooked laneways into vibrant spaces. However, these transformations rely on the activities in the lane and the interventions are largely landscaping and installations. By investigating the successful regeneration of previously undesirable and neglected spaces through architectural re-imagination, this thesis identify laneways to be a potential site to the urgent need for shelters.  The architectural experiments and design development are informed by the combination of site challenges and programme to form an overall design-led research. The thesis tests how temporary modular design has a significant role in the design of economic and adaptable solutions for the increasing issue of homelessness. This establishes that through a critical design, we may shelter those in desperate need within the urban context. The architecture provides a safe environment that is empathetic to its users and the larger urban scale while also creating a statement and awareness to homelessness. The thesis concludes with the design framework for a single test site and assesses its suitability for future application to other leftover spaces in the city.</p>

Sign in / Sign up

Export Citation Format

Share Document