scholarly journals The Effects of Grout Curtain Parameters on Uplift and Piping Phenomenon; Case Study: Sattarkhan Dam

Hydrology ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 71
Author(s):  
Kambiz Meshkabadi ◽  
Yousef Zandi

Design of earth dams and their issues during and after construction is very important for residents downstream of the dam because of the potential risks and possible breakdowns. In the design of dams, various forces influence the dam body, including uplift pressure and piping phenomenon which should be considered in order to ensure the safety of the dam. Among the measures taken to prevent the washing away phenomenon, the reduction of the output gradient, and the leakage discharge from beneath the hydraulic structures, construction of the grout curtain and installation of the drainage are applicable. Therefore, in order to investigate the effect of various parameters such as the gradient angle of the grout curtain, length, and distance and the number of grout curtains, as well as the length of the drainage on the pressure and output gradient of the numerical models, were considered in current study. For this purpose, the SEEP/W software was used for modeling on Sattarkhan Dam as a case study. The results of the analysis showed that the use of the Qa’im grout curtain at the upstream of the dam has the highest resistance against the pressure and piping phenomenon. The results also showed that increase in the length of the curtain of the water seal increases safety against uplift and piping phenomenon. The use of further spacing between the two grout curtains under the core of the dam led to increase in overall pressure or reduction in safety against uplift pressure. Increase in the length of the horizontal drainage reduced the effects of uplift pressure and output gradient. Results show that period of 70 to 110 degree is appropriate for curtain angle and setting curtain in upstream of dam core with angle of 70 to 80 degree is optimum and economic. A length of 30 m is optimum for curtain. The number of 2 curtains is also optimum. Studying various scenarios of distance of 2 curtains in dam core indicates that distance of 6 m is optimum and also length of 18 m for horizontal drainage is optimum.

2019 ◽  
Vol 15 (S354) ◽  
pp. 439-442
Author(s):  
Salvo L. Guglielmino ◽  
Peter R. Young ◽  
Francesca Zuccarello ◽  
Paolo Romano ◽  
Mariarita Murabito

AbstractWe report on multi-wavelength ultraviolet (UV) high-resolution observations taken with the IRIS satellite during the emergence phase of an emerging flux region embedded in the unipolar plage of active region NOAA 12529. These data are complemented by measurements taken with the spectropolarimeter aboard the Hinode satellite and by observations from SDO.In the photosphere, we observe the appearance of opposite emerging polarities, separating from each other, and cancellation with a pre-existing flux concentration of the plage.In the upper atmospheric layers, recurrent brightenings resembling UV bursts, with counterparts in all UV/EUV filtergrams, are identified in the EFR site. In addition, plasma ejections are observed at chromospheric level. Most important, we unravel a signature of plasma heated up to 1 MK detecting Fe XII emission in the core of the brightening sites.Comparing these findings with previous observations and numerical models, we suggest evidence of several long-lasting, small-scale magnetic reconnection episodes between the new bipolar EFR and the ambient field.


2012 ◽  
Vol 6 (1-3) ◽  
pp. 309-329
Author(s):  
Claudia V. Camp

I propose that the notion of possession adds an important ideological nuance to the analyses of iconic books set forth by Martin Marty (1980) and, more recently, by James Watts (2006). Using the early second century BCE book of Sirach as a case study, I tease out some of the symbolic dynamics through which the Bible achieved iconic status in the first place, that is, the conditions in which significance was attached to its material, finite shape. For Ben Sira, this symbolism was deeply tied to his honor-shame ethos in which women posed a threat to the honor of his eternal name, a threat resolved through his possession of Torah figured as the Woman Wisdom. What my analysis suggests is that the conflicted perceptions of gender in Ben Sira’s text is fundamental to his appropriation of, and attempt to produce, authoritative religious literature, and thus essential for understanding his relationship to this emerging canon. Torah, conceived as female, was the core of this canon, but Ben Sira adds his own literary production to this female “body” (or feminized corpus, if you will), becoming the voice of both through the experience of perfect possession.


2017 ◽  
Vol 16 (7) ◽  
pp. 1415-1421
Author(s):  
Yasemin Tabak ◽  
Senol Yildiz ◽  
Volkan Enc ◽  
Mustafa Kara ◽  
Emine Acet

2018 ◽  
Vol 6 (3) ◽  
pp. 20-28
Author(s):  
Faisal Al Tabatabaie ◽  
Dhabia Sabeeh Al Waily

The use of cutoffs underneath the hydraulic structures is considered a safe solution to ensure the stability of hydraulic structure against uplift pressure and piping phenomenon in addition to the sliding and overturning forces of the water. These cutoffs are used at critical sections underneath the floor of hydraulic structure to substitute with their depths the horizontal lengths of the creep line of the hydraulic structure base. In this paper, the experimental method- by using electrical analogue model- was carried out to plot the flow net and study the efficiency of the front and rear faces of the cutoffs for dissipating the potential energy of the percolating water underneath the floor of hydraulic structure. An electrical analogue model which was used in this study consists of twenty five models with different depths of upstream and downstream cutoffs. After plotting the flow net for all models, it is concluded that the efficiency of the inner sides are less than that of the outer sides which were investigated before in this topic of this work that both faces reduction values in the uplift pressure are considered the same, where the efficiency of the outer face of upstream cutoff is (70.35) % and for the inner face is (29.64)%, while for the downstream cutoff the efficiency for the outer face is (76.21)% and for the inner face is (23.79)% .


2020 ◽  
Author(s):  
George Karagiannakis

This paper deals with state of the art risk and resilience calculations for industrial plants. Resilience is a top priority issue on the agenda of societies due to climate change and the all-time demand for human life safety and financial robustness. Industrial plants are highly complex systems containing a considerable number of equipment such as steel storage tanks, pipe rack-piping systems, and other installations. Loss Of Containment (LOC) scenarios triggered by past earthquakes due to failure on critical components were followed by severe repercussions on the community, long recovery times and great economic losses. Hence, facility planners and emergency managers should be aware of possible seismic damages and should have already established recovery plans to maximize the resilience and minimize the losses. Seismic risk assessment is the first step of resilience calculations, as it establishes possible damage scenarios. In order to have an accurate risk analysis, the plant equipment vulnerability must be assessed; this is made feasible either from fragility databases in the literature that refer to customized equipment or through numerical calculations. Two different approaches to fragility assessment will be discussed in this paper: (i) code-based Fragility Curves (FCs); and (ii) fragility curves based on numerical models. A carbon black process plant is used as a case study in order to display the influence of various fragility curve realizations taking their effects on risk and resilience calculations into account. Additionally, a new way of representing the total resilience of industrial installations is proposed. More precisely, all possible scenarios will be endowed with their weighted recovery curves (according to their probability of occurrence) and summed together. The result is a concise graph that can help stakeholders to identify critical plant equipment and make decisions on seismic mitigation strategies for plant safety and efficiency. Finally, possible mitigation strategies, like structural health monitoring and metamaterial-based seismic shields are addressed, in order to show how future developments may enhance plant resilience. The work presented hereafter represents a highly condensed application of the research done during the XP-RESILIENCE project, while more detailed information is available on the project website https://r.unitn.it/en/dicam/xp-resilience.


Author(s):  
Dr. Vidhyasri M ◽  
Dr. S. M. Pasha

Introduction: This is the case report of child who was diagnosed with LCA reported with complaints of large-amplitude, slow-frequency, roving nystagmus, frequent tendency to press on his eyes, enopthalmos, with completely normal ophthalmoscopic examination with normal appearing optic nerve and retina and has a non recordable ERG; considering this condition under the lines of Vataja Nanatmaja Vyadhi treatment was structured to render effective visual rehabilitation which showed marked results. Methods: 4 years old male child who was diagnosed with lebers congenital amaurosis was brought by his parents to Eye OPD, GAMC, Bengaluru. The presentation of this case includes bibliographic review of the subject, presentation of a clinical case and description of the importance of Ayurvedic prespective of handling of these patients. Results: The child showed improvement in fixing for light and also nystagmus showed marked improvement and there were considerable behavioural changes observed. Discussion: It is important to deepen the environment of the disease to know the possible implications in Ayurvedic management, recognize the magnitude of visual disability that our patient presents for the establishment of the treatment plan and provide an integral care of excellence in an interdisciplinary way in favor of visual rehabilitation of our patients and also help to restore quality of life with no potential risks of side effects.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 29
Author(s):  
Mahdi Shadabfar ◽  
Cagri Gokdemir ◽  
Mingliang Zhou ◽  
Hadi Kordestani ◽  
Edmond V. Muho

This paper presents a review of the existing models for the estimation of explosion-induced crushed and cracked zones. The control of these zones is of utmost importance in the rock explosion design, since it aims at optimizing the fragmentation and, as a result, minimizing the fine grain production and recovery cycle. Moreover, this optimization can reduce the damage beyond the set border and align the excavation plan with the geometric design. The models are categorized into three groups based on the approach, i.e., analytical, numerical, and experimental approaches, and for each group, the relevant studies are classified and presented in a comprehensive manner. More specifically, in the analytical methods, the assumptions and results are described and discussed in order to provide a useful reference to judge the applicability of each model. Considering the numerical models, all commonly-used algorithms along with the simulation details and the influential parameters are reported and discussed. Finally, considering the experimental models, the emphasis is given here on presenting the most practical and widely employed laboratory models. The empirical equations derived from the models and their applications are examined in detail. In the Discussion section, the most common methods are selected and used to estimate the damage size of 13 case study problems. The results are then utilized to compare the accuracy and applicability of each selected method. Furthermore, the probabilistic analysis of the explosion-induced failure is reviewed using several structural reliability models. The selection, classification, and discussion of the models presented in this paper can be used as a reference in real engineering projects.


2020 ◽  
pp. 095792652097721
Author(s):  
Janaina Negreiros Persson

In this article, we explore how the discourses around gender are evolving at the core of Brazilian politics. Our focus lies on the discourses at the public hearing on the bill 3.492/19, which aimed at including “gender ideology” on the list of heinous crimes. We aim to identify the deputies’ linguistic representation of social actors as pertaining to in- and outgroups. In addition, the article analyzes through Critical Discourse Analysis how the terminology gender is represented in this particular hearing. The analysis shows how some of the conservative parliamentarians give a clearly negative meaning to the term gender, by labeling it “gender ideology” and additionally connecting it with heinous crimes. We propose that the re-signification of “gender ideology,” from rhetorical invention to heinous crime, is not only an attempt to undermine scientific gender studies but also a way for conservative deputies to gain more political power.


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