scholarly journals Comparison of Large Woody Debris Prototypes in a Large Scale Non-flume Physical Model

2018 ◽  
Vol 40 ◽  
pp. 05010
Author(s):  
Brian Perry ◽  
Colin Rennie ◽  
Andrew Cornett ◽  
Paul Knox

Due to excessive rainfall in June of 2013, several rivers located in and near the City of Calgary, Canada experienced significant flooding events. These events caused severe damage to infrastructure throughout the city, precipitating a renewed interest in flood control and mitigation strategies for the area. A major potential strategy involves partial diversion of Elbow River flood water to the proposed Springbank Off-Stream Storage Reservoir. A large scale physical model study was conducted to optimize and validate the design of a portion of the new project. The goals of the physical model were to investigate diversion system behaviors such as flow rates, water levels, sediment transport and, debris accumulation, and optimize the design of new flow control structures to be constructed on the Elbow River. In order to accurately represent the behavior of debris within the system due to flooding, large woody debris created from natural sources was utilized in the physical model and its performance was compared to that of debris of the same size fabricated from pressed cylindrical wood dowels. In addition to comparing the performance of these two debris types, the impact of root wads on debris damming was also investigated. Significant differences in damming behavior was shown to exist between the natural debris and the fabricated debris, while the impact of root wad on damming affected the dam structure and formation. The results of this experiment indicate that natural debris is preferred for studies involving debris accumulation.

2021 ◽  
Author(s):  
Michel Schreinemachers ◽  
Wiebe Strick

<p>Should a bridge always be functional and accessible? Should it always fulfil its purpose? This seemingly self- evident question is a key question in footbridge design that is oriented towards creating experiences.</p><p>Footbridges are able to successfully enriches our experience of a certain context or landscape, it cannot be functional all the time, under all environmental conditions, weather and seasons. A good example is the Zalige bridge designed as part of the Room for the River, a large-scale national program for inland flood- protection in the Netherlands. Build upon the floodplains within a newly created river-park by the city of Nijmegen, the Zalige bridge’s curved shape stands in direct relationship to the fluctuating water levels of the river. When water levels rise, the bridge partially submerges, becoming only accessible through steppingstones. At peak heights, the bridge disappears completely, becoming a metaphor for our relationship to the water.</p><p>“Building a bridge that fails to fulfil its sole purpose of containing the water; this can only be pulled off in the Netherlands.” – jury Dutch Design Awards about the Zalige bridge.</p><p>The loss of functionality is directly related to the creation of an experience. When the water levels rose in January 2018, the bridge became the prime location to experience the changing landscape. It shows that engineering a bridge is not solely focussed on the most efficient engineering, but for the purpose it fulfils as for society. For most pedestrian bridges where the perception of the user is on a different level as for a highway bridge, functionality provides more than just cost driven or efficiency driven parameters. It is more related to the added value for the community. When design not solemnly derives from the sheer taste and predilection of the designer but is based on the user’s experience, it generates a durable relation with a feeling of ownership of its users. The key is to create this experience in an elegant and natural way and not forced or dictated. It should be people's own unique discovery and should not be imposed.</p>


2020 ◽  
Vol 24 (1) ◽  
pp. 13-44
Author(s):  
Diana Mihnea

During the 1920s, the city of Sibiu expanded by approximately 250 hectares, with an area that was three times larger than its historical core. This great expansion was the result of the application of the agrarian reform, whose laws allowed and encouraged the creation of new building plots in the cities of Transylvania, Banat, Crișana and Maramureș. Although this was the largest territorial growth of the city up until that time, it was not controlled by the municipality and its Technical Office. In fact, the city authorities were excluded from most stages of the decision-making process. All the decisions were taken by the central and local institutions of the Ministry of Agriculture and Domains that were in charge with the application of the agrarian reform. The territorial expansion was not based on any large-scale studies regarding the needs of the city or the impact on its future development. In fact, the proportions and the directions of the city’s expansion were dictated mostly by the number of accepted requests for building plots and by the position of the areas that could be expropriated and that were suitable to be parcelled. The creation of the large new allotments was simultaneous with the efforts of the municipality to draft a systematisation plan that was now urgently necessary, given the rapidly changing situation of the city, and it was imposed by the new administrative legislation of Romania. So, shortly after the parceling plans were issued and the new building plots were distributed to those entitled, a preliminary systematization plan – drafted between 1926 and 1928 – proposed the revision of the new allotments and the modification of the procedure for assigning the building plots according to a system that would allow a gradual territorial growth of the city. Hence, during the second half of the 1920s and the beginning of the 1930s there were ample negotiations over the new urban territory, involving not only the Ministry of Agriculture and Domains, but also the Ministry of Interior and the Superior Technical Council. In the end, after almost a decade of negotiations, only minor adjustments were made to the allotments and the provisions of the systematisation plan were only partly applied.


2011 ◽  
Vol 4 (1) ◽  
pp. 193-211 ◽  
Author(s):  
Xin Gu

This paper deals with the development of ’art clusters’ and their relocation in the city of Shanghai. It first looks at the revival of the city’s old inner city industrial area (along banks of Suzhou River) through ’organic’ or ’alternative’ artist-led cultural production; second, it describes the impact on these activities of the industrial restructuring of the wider city, reliant on large-scale real estate development, business services and global finance; and finally, outlines the relocation of these arts (and related) cultural industries to dispersed CBD locations as a result of those spatial, industrial and policy changes.


Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 810 ◽  
Author(s):  
Antonio Barragán-Escandón ◽  
Esteban Zalamea-León ◽  
Julio Terrados-Cepeda

Previous research has assessed the potential of solar energy against possible demand; however, the sustainability issues associated with the use of large-scale photovoltaic deployment in urban areas have not been jointly established. In this paper, the impact of photovoltaic energy in the total urban energy mix is estimated using a series of indicators that consider the economic, environmental and social dimensions. These indicators have been previously applied at the country level; the main contribution of this research is applying them at the urban level to the city of Cuenca, Ecuador. Cuenca is close to the equatorial line and at a high altitude, enabling this area to reach the maximum self-supply index because of the high irradiation levels and reduced demand. The solar potential was estimated using a simple methodology that applies several indexes that were proven reliable in a local context considering this particular sun path. The results demonstrate that the solar potential can meet the electric power demand of this city, and only the indicator related to employment is positive and substantially affected. The indicators related to the price of energy, emissions and fossil fuel dependency do not change significantly, unless a fuel-to-electricity transport system conversions take place.


Author(s):  
Ahmadreza Faghih Imani ◽  
Chris Harding ◽  
Siva Srikukenthiran ◽  
Eric J. Miller ◽  
Khandker Nurul Habib

Smartphones offer a potential alternative to collect high-quality information on the travel patterns of individuals without burdening the respondents with reporting every detail of their travel. Smartphone apps have recently become a common tool for travel survey data collection around the world, especially for multiday surveys. However, there still exists a lack of systematic assessment of issues related to smartphone app-based surveys, such as the impact of app design or the recruitment method on the collected data. Through a large-scale experiment (named the City Logger), this paper assesses the data produced by the City Logger app, to better understand recruitment avenues (targeted invitation versus crowdsourcing), and examine differences in respondents’ travel behavior recruited through crowdsourcing methods. The paper also examines how app design, and particularly the user input method for trip validation, influences participants’ responses. The results indicate that, while crowdsourcing recruitment is promising, it might not yet be the best way to capture a true representation of the population. For app design, a combination of real-time and travel diary approaches is recommended. An ideal app would prompt users real-time and create a travel diary, so users can validate, edit, or delete the recorded information.


Zoosymposia ◽  
2016 ◽  
Vol 10 (1) ◽  
pp. 384-392
Author(s):  
RIE SAITO ◽  
KAZUKI SEKINÉ ◽  
KOJI TOJO

The channels of almost all rivers in Japan have been fixed through the construction of artificial riverbanks to control flooding. In addition, to prevent flooding, maintenance works including the removal of gravel from the channels must be conducted regularly. As a result, the level of most riverbeds within river channels has been lowered, and riverbanks have become far steeper. These large changes to riverside environments have significantly altered the type of habitats available to plants, causing the level of vegetation growth on the riverside to increase. To improve such flood control methods, a new excavation project has commenced in the central area of the Chikuma-gawa River basin, under the auspices of the newly commissioned “Government Nature Restoration Project”. As part of this project, a large shallow environment approximately 1 km in length along the river’s course was newly created. We have attempted to evaluate the impact of this project and the subsequent environmental response, focusing on two dominant benthos, Stenopsyche marmorata and Isonychia japonica, particularly the dynamics of their genetic structure and diversity. Following the excavation of riverbanks and channels, the population density reached the same levels as at the control site, in a relatively short period of time. This is because the research site was limited to a small area within the large-scale river basin, with robust habitats located both upstream and downstream. The two target species in this study represent typical dominant species in the central basin of this river, and occur at high density. In other words, they could be transferred smoothly from the surrounding robust habitats, especially by the flow from upstream.


2015 ◽  
Vol 15 (19) ◽  
pp. 27041-27085
Author(s):  
K. Markakis ◽  
M. Valari ◽  
M. Engardt ◽  
G. Lacressonnière ◽  
R. Vautard ◽  
...  

Abstract. Ozone, PM10 and PM2.5 concentrations over Paris, France and Stockholm, Sweden were modeled at 4 and 1 \\unit{km} horizontal resolutions respectively for the present and 2050 periods employing decade-long simulations. We account for large-scale global climate change (RCP-4.5) and fine resolution bottom-up emission projections developed by local experts and quantify their impact on future pollutant concentrations. Moreover, we identify biases related to the implementation of regional scale emission projections over the study areas by comparing modeled pollutant concentrations between the fine and coarse scale simulations. We show that over urban areas with major regional contribution (e.g., the city of Stockholm) the bias due to coarse emission inventory may be significant and lead to policy misclassification. Our results stress the need to better understand the mechanism of bias propagation across the modeling scales in order to design more successful local-scale strategies. We find that the impact of climate change is spatially homogeneous in both regions, implying strong regional influence. The climate benefit for ozone (daily average and maximum) is up to −5 % for Paris and −2 % for Stockholm city. The joined climate benefit on PM2.5 and PM10 in Paris is between −10 and −5 % while for Stockholm we observe mixed trends up to 3 % depending on season and size class. In Stockholm, emission mitigation leads to concentration reductions up to 15 % for daily average and maximum ozone and 20 % for PM and through a sensitivity analysis we show that this response is entirely due to changes in emissions at the regional scale. On the contrary, over the city of Paris (VOC-limited photochemical regime), local mitigation of NOx emissions increases future ozone concentrations due to ozone titration inhibition. This competing trend between the respective roles of emission and climate change, results in an increase in 2050 daily average ozone by 2.5 % in Paris. Climate and not emission change appears to be the most influential factor for maximum ozone concentration over the city of Paris, which may be particularly interesting in a health impact perspective.


2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Angga Syahputra ◽  
Mukhtasar Mukhtasar

AbstractThe Indonesian government has taken various policies to protect its citizens from the Covid-19 outbreak. Large-Scale Social Restrictions (PSBB) to impose a curfew have become several policies taken by several cities in Indonesia to stop the spread of Covid-19. Since WHO declared a pandemic, Covid-19 has had an impact on all aspects of life including socio-economics. Lhokseumawe is an industrial city which is mostly inhabited by residents from outside the city which is designated as a red zone. Various policies issued, such as the imposition of curfews, prohibitions on gathering in cafes, social distancing, wearing masks, and other policies, generally have no significant impact on socio-economic aspects. For this reason, researchers want to see the impact of Covid-19 on the socio-economic aspects of the people of Lhokseumawe City. The method used in this study used qualitative methods with the main data source obtained from observations, as a complement used literature studies and the results of previous research. As of October 2020, Lhokseumawe is still a red zone, but many people do not heed government policies, even socio-economic activities appear to be running normally. The results also showed that there was no significant change in the socio-economic aspects of the community in Lhokseumawe City. This research also explains important steps that are useful for stakeholders to decide on Covid-19 and anticipate its impact.


2019 ◽  
Vol 9 (15) ◽  
pp. 3182 ◽  
Author(s):  
Salvador García-Ayllón ◽  
Antonio Tomás ◽  
José Luis Ródenas

The analysis of damage in cities after an earthquake to implement mitigation strategies of seismic risk is a complex job that is usually full of uncertainties. Numerous variables affect the final result of the observable damage in a set of buildings in an urban area. The use of methodologies capable of providing global explanations beyond the traditional unidisciplinary approach of disciplines, such as structural analysis, earthquake engineering, geotechnics, or seismology, can be very useful for improving the behavior of our cities against earthquakes. This article presents geostatistical post-earthquake analysis, an innovative approach in this field of research based on GIS spatial statistical tools to evaluate the importance of the different variables after an earthquake that may have caused damage in a city. This new framework will be applied to analyze, from a geostatistical perspective, the damage levels observed in the city of Lorca (Spain) after the earthquake of 2011; a case study where various studies have proposed different measures to mitigate the impact of future earthquakes as a consequence of focusing on different phenomena as the main variable for the damage produced. A bivariate GIS assessment will allow spatial correlation of the problems detected from a statistical point of view (inadequate design of buildings, age of the real estate stock, inefficient urban planning configurations, geological risk, etc.) and the different levels of damage that the technicians who participated in the post-earthquake phase evaluated in the city. The results obtained will allow one to hierarchize the importance of the different detected phenomena to prepare the city better against future earthquakes and to elaborate an improved seismic mitigation strategy.


Pondasi ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 94
Author(s):  
Andika Duwi Prasetyo ◽  
Agus Sarwo Edy Sudrajat

ABSTRAK Bencana banjir di Kota Semarang sudah tak asing lagi bagi masyarakat Semarang, khususnya pada wilayah timur Kota Semarang, bencana banjir di Kota Semarang disebabkan beberapa faktor antara lain curah hujan yang tinggi, permukaan tanah yang lebih rendah dibandingkan permukaan air laut, dan banyaknya sampah yang tersumbat pada saluran drainase. Bencana banjir yang disebabkan oleh beberapa faktor tersebut berdampak buruk bagi Kota Semarang khususnya pada Kelurahan Tlogosari, Kecamatan Pedurungan, dampak dari bencana banjir tersebut mengakibatkan kerusakan pada jalan, kemacetan, dan dapat menyebabkan penyakit pada lingkungan di wilayah deliniasi di Kelurahan Tlogosari, Kecamatan Pedurungan. Perlu adanya penanganan untuk mengatasi bencana banjir di wilayah deliniasi Kelurahan Tlogosari, Kecamatan Pedurungan, seperti upaya melakukan pembangunan sistem pengendali banjir dan pada sistem drainase, dan pembangunan sumur resapan air pada setiap permukiman, serta melakukan konservasi secara berkala untuk sungai maupun sistem drainase di wilayah deliniasi Kelurahan Tlogosari, Kecamatan Pedurungan. Kata Kunci : Identifikasi; Banjir; Tlogosari ABSTRACT The flood disaster in Semarang City is familiar to the people of Semarang, especially in the eastern area of Semarang City, the flood disaster in Semarang City is caused by several factors, including high rainfall, lower land surface than sea level, and the amount of clogged garbage. on the drainage channel. The flood disaster caused by several of these factors had a bad impact on the city of Semarang, especially in Tlogosari Village, Pedurungan District, the impact of the flood disaster caused damage to roads, congestion, and could cause disease in the environment in the delineation area in Tlogosari Village, Pedurungan District. There is a need for handling to overcome flood disasters in the delineation area of Tlogosari Village, Pedurungan District, such as efforts to build a flood control system and drainage system, and build water infiltration wells in each settlement, as well as carry out periodic conservation of rivers and drainage systems in the delineation area. Tlogosari Village, Pedurungan District.Keyword: Identification;Flood; Tlogosari


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