Magat Dams: Design of internal filters and drains

1983 ◽  
Vol 20 (3) ◽  
pp. 491-501 ◽  
Author(s):  
Sydney F. Hillis ◽  
E. Glen Truscott
Keyword(s):  
Cross Section ◽  
Large Scale ◽  
Filter Design ◽  
The Philippines ◽  
Core Material ◽  
Project Area ◽  
Intact Core ◽  
Dam Core ◽  
Large Scale Tests ◽  
Design And Testing

This paper describes the design and testing for the filter and drain zones for the Magat Dams. These four rockfill structures are located in the Philippines and range in height from 25 to 115 m. Construction was completed in late 1982. The project area is in a seismically active region and, as a result, the dam design had to be inherently conservative. This resulted in a highly zoned cross section and the provision of several wide filter and drain zones. The design of the filters and drains were checked by a series of large scale tests involving a 580 mm diam. permeameter and a large flume. Owing to the risk, however slight, of the dam cores being cracked during a major earthquake, the tests were carried out using both intact core material and core material into which a crack had been introduced. The results of the testing indicate that: (a) the filter gradations chosen are satisfactory, (b) it was prudent at Magat to introduce two filter zones between the dam core and the chimney drain, (c) conventional filter criteria are overly conservative when applied to the Magat core material, and (d) conventional criteria do not apply to the case of a cracked core. In this case the protective filter should contain a small amount of noncohesive fines. This is in accordance with developing practice. Keywords: filter design, testing, dam design, seismic effects, cracking.

Rigid latticed steel frames: two large-scale tests and failure predictions

1987 ◽  
Vol 14 (5) ◽  
pp. 602-613 ◽  
Author(s):  
John S. Ellis
Keyword(s):  
Cross Section ◽  
Large Scale ◽  
Static Load ◽  
Yield Criterion ◽  
Elastic Stiffness ◽  
Free Standing ◽  
Stiffness Matrices ◽  
Failure Loads ◽  
Uniform Cross Section ◽  
Large Scale Tests

This work is concerned with the predictions of failure under static load for two identical free-standing latticed cantilever frames. Each structure was 3 m high and consisted of three storeys with panel points 1 m apart; in plan it was 1 m2; its diagonals were at 45° in the form of St. Andrew's cross; all joints were welded and were considered rigid. The four bases were bolted to the laboratory floor and the static load was applied at the top as two compressive horizontal forces parallel to the sides of the structure. The individual members were all solid mild steel round rods; the verticals were of uniform cross section of 25.4 mm in diameter with a slenderness of 157; the horizontal cross-arms were of uniform cross section of 19 mm in diameter; and the diagonals were of uniform cross section of 15.9 mm in diameter. The diagonals were cut at their mid-lengths and welded to give a flush joint.The total horizontal loads that caused failure of the two structures were 79.6 and 79.2 kN. In both cases failure occurred by the sudden buckling of one of the bottom-storey vertical legs, inwards towards the centre of the structure. Also upon failure, the diagonals in the bottom storey of the compression face buckled inwards and the compression diagonal of the side contiguous to the buckled leg also buckled.Three elastic stiffness matrices were used to predict the failure loads: (1) linear with yield criterion, 116 kN; (2) stability with change in sign of the total potential energy, 66 kN; and (3) bowing with the criterion of maximum curvature of the load–deflection curve, 80 kN. The failure loads of the two structures were thus accurately predicted by the bowing matrix. Key words: latticed rigid frames, large-scale tests, bowing matrix, steel.

Stratigraphic Architecture of a Fluvial-lacustrine Basin-fill Succession at Desolation Canyon, Uinta Basin, Utah: Reference to Walthers’ Law and Implications for the Petroleum Industry

2016 ◽  
Vol 53 (1) ◽  
pp. 5-28 ◽  
Author(s):  
Grace Ford ◽  
David Pyles ◽  
Marieke Dechesne
Keyword(s):  
Cross Section ◽  
Oil Shale ◽  
Large Scale ◽  
Green River Formation ◽  
Sand Content ◽  
Fluvial System ◽  
Uinta Basin ◽  
Green River ◽  
Lacustrine Basin ◽  
Basin Fill

A continuous window into the fluvial-lacustrine basin-fill succession of the Uinta Basin is exposed along a 48-mile (77-kilometer) transect up the modern Green River from Three Fords to Sand Wash in Desolation Canyon, Utah. In ascending order the stratigraphic units are: 1) Flagstaff Limestone, 2) lower Wasatch member of the Wasatch Formation, 3) middle Wasatch member of the Wasatch Formation, 4) upper Wasatch member of the Wasatch Formation, 5) Uteland Butte member of the lower Green River Formation, 6) lower Green River Formation, 7) Renegade Tongue of the lower Green River Formation, 8) middle Green River Formation, and 9) the Mahogany oil shale zone marking the boundary between the middle and upper Green River Formations. This article uses regional field mapping, geologic maps, photographs, and descriptions of the stratigraphic unit including: 1) bounding surfaces, 2) key upward stratigraphic characteristics within the unit, and 3) longitudinal changes along the river transect. This information is used to create a north-south cross section through the basin-fill succession and a detailed geologic map of Desolation Canyon. The cross section documents stratigraphic relationships previously unreported and contrasts with earlier interpretations in two ways: 1) abrupt upward shifts in the stratigraphy documented herein, contrast with the gradual interfingering relationships proposed by Ryder et al., (1976) and Fouch et al., (1994), 2) we document fluvial deposits of the lower and middle Wasatch to be distinct and more widespread than previously recognized. In addition, we document that the Uteland Butte member of the lower Green River Formation was deposited in a lacustrine environment in Desolation Canyon. Two large-scale (member-scale) upward patterns are noted: Waltherian, and non-Waltherian. The upward successions in Waltherian progressions record progradation or retrogradation of a linked fluvial-lacustrine system across the area; whereas the upward successions in non-Waltherian progressions record large-scale changes in the depositional system that are not related to progradation or retrogradation of the ancient lacustrine shoreline. Four Waltherian progressions are noted: 1) the Flagstaff Limestone to lower Wasatch Formation member records the upward transition from lacustrine to fluvial—or shallowing-upward succession; 2) the upper Wasatch to Uteland Butte records the upward transition from fluvial to lacustrine—or a deepening upward succession; 3) the Uteland Butte to Renegade Tongue records the upward transition from lacustrine to fluvial—a shallowing-upward succession; and 4) the Renegade Tongue to Mahogany oil shale interval records the upward transition from fluvial to lacustrine—a deepening upward succession. The two non-Waltherian progressions in the study area are: 1) the lower to middle Wasatch, which records the abrupt shift from low to high net-sand content fluvial system, and 2) the middle to upper Wasatch, which records the abrupt shift from high to intermediate net-sand content fluvial system.

New Directions in Latino/a/x Histories of Education: Comparative Studies in Race, Language, Law, and Higher Education

2020 ◽  
Vol 60 (4) ◽  
pp. 612-622
Author(s):  
Rosina Lozano
Keyword(s):  
Higher Education ◽  
Civil Rights ◽  
Race And Ethnicity ◽  
Large Scale ◽  
Student Activism ◽  
The United States ◽  
The Philippines ◽  
Language Instruction ◽  
Historical Inquiry ◽  
Legal Cases

The twenty-first century has seen a surge in scholarship on Latino educational history and a new nonbinary umbrella term, Latinx, that a younger generation prefers. Many of historian Victoria-María MacDonald's astute observations in 2001 presaged the growth of the field. Focus has increased on Spanish-surnamed teachers and discussions have grown about the Latino experience in higher education, especially around student activism on campus. Great strides are being made in studying the history of Spanish-speaking regions with long ties to the United States, either as colonies or as sites of large-scale immigration, including Puerto Rico, Cuba, and the Philippines. Historical inquiry into the place of Latinos in the US educational system has also developed in ways that MacDonald did not anticipate. The growth of the comparative race and ethnicity field in and of itself has encouraged cross-ethnic and cross-racial studies, which often also tie together larger themes of colonialism, language instruction, legal cases, and civil rights or activism.

scholarly journals 1068. Large-Scale Migration and the Changing Viral Hepatitis Prevalences in North America: A modeling approach

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S563-S563
Author(s):  
Kenneth A Valles ◽  
Lewis R Roberts
Keyword(s):  
United States ◽  
Viral Hepatitis ◽  
Large Scale ◽  
Country Of Origin ◽  
Human Movement ◽  
High Volume ◽  
The United States ◽  
The Philippines ◽  
Outcome Data ◽  
Treatment Programs

Abstract Background Infection by hepatitis B and C viruses causes inflammation of the liver and can lead to cirrhosis, liver failure, and hepatocellular carcinoma. The WHO’s ambition to eliminate viral hepatitis by 2030 requires strategies specific to the dynamic disease profiles each nation faces. Large-scale human movement from high-prevalence nations to the United States and Canada have altered the disease landscape, likely warranting adjustments to present elimination approaches. However, the nature and magnitude of the new disease burden remains unknown. This study aims to generate a modeled estimate of recent HBV and HCV prevalence changes to the United States and Canada due to migration. Methods Total migrant populations from 2010-2019 were obtained from United Nations Migrant Stock database. Country-of-origin HBV and HCV prevalences were obtained for the select 40 country-of-origin nations from the Polaris Observatory and systematic reviews. A standard pivot table was used to evaluate the disease contribution from and to each nation. Disease progression estimates were generated using the American Association for the Study of the Liver guidelines and outcome data. Results Between 2010 and 2019, 7,676,937 documented migrants arrived in US and Canada from the selected high-volume nations. Primary migrant source regions were East Asia and Latin America. Combined, an estimated 878,995 migrants were HBV positive, and 226,428 HCV positive. The majority of both migrants (6,477,506) and new viral hepatitis cases (HBV=840,315 and HCV=215,359) were found in the United States. The largest source of HBV cases stemmed from the Philippines, and HCV cases from El Salvador. Conclusion Massive human movement has significantly changed HBV and HCV disease burdens in both the US and Canada over the past decade and the long-term outcomes of cirrhosis and HCC are also expected to increase. These increases are likely to disproportionally impact individuals of the migrant and refugee communities and screening and treatment programs must be strategically adjusted in order to reduce morbidity, mortality, and healthcare expenses. Disclosures All Authors: No reported disclosures

Harvest rate of sooty shearwaters (Puffinus griseus) by Rakiura Māori: a potential tool to monitor population trends?

2004 ◽  
Vol 31 (3) ◽  
pp. 319 ◽  
Author(s):  
Jane Catherine Kitson
Keyword(s):  
New Zealand ◽  
Cross Section ◽  
Large Scale ◽  
Population Change ◽  
Population Trends ◽  
Harvest Rate ◽  
General Index ◽  
Careful Screening ◽  
Potential Tool

Sooty shearwaters (tītī, muttonbird, Puffinus griseus) are highly abundant migratory seabirds, which return to breeding colonies in New Zealand. The Rakiura Māori annual chick harvest on islands adjacent to Rakiura (Stewart Island), is one of the last large-scale customary uses of native wildlife in New Zealand. This study aimed to establish whether the rate at which muttonbirders can extract chicks from their breeding burrows indicates population trends of sooty shearwaters. Harvest rates increased slightly with increasing chick densities on Putauhinu Island. Birders' harvest rates vary in their sensitivities to changing chick density. Therefore a monitoring panel requires careful screening to ensure that harvest rates of the birders selected are sensitive to chick density, and represents a cross-section of different islands. Though harvest rates can provide only a general index of population change, it can provide an inexpensive and feasible way to measure population trends. Detecting trends is the first step to assessing the long-term sustainability of the harvest.

scholarly journals Politician Family Networks and Electoral Outcomes: Evidence from the Philippines

2017 ◽  
Vol 107 (10) ◽  
pp. 3006-3037 ◽  
Author(s):  
Cesi Cruz ◽  
Julien Labonne ◽  
Pablo QuerubÍn
Keyword(s):  
Large Scale ◽  
The Philippines ◽  
Network Centrality ◽  
Family Network ◽  
Family Networks ◽  
Electoral Success ◽  
Large Scale Data ◽  
Electoral Outcomes ◽  
Elite Status ◽  
Scale Data

We demonstrate the importance of politician social networks for electoral outcomes. Using large-scale data on family networks from over 20 million individuals in 15,000 villages in the Philippines, we show that candidates for public office are disproportionately drawn from more central families and family network centrality contributes to higher vote shares during the elections. Consistent with our theory of political intermediation, we present evidence that family network centrality facilitates relationships of political exchange. Moreover, we show that family networks exercise an effect independent of wealth, historical elite status, or previous electoral success. (JEL D72, D85, O17, Z13)

Disaster impacts in a port-city; learning from Beirut's  Port explosion

2021 ◽  
Author(s):  
Steluta topalov
Keyword(s):  
Large Scale ◽  
Focal Point ◽  
Transportation System ◽  
The Philippines ◽  
Lessons Learned ◽  
Social Dimension ◽  
Global Network ◽  
Port Cities ◽  
Residential Units ◽  
The Impact

<p>On 4 august 2020, one of the biggest non-nuclear explosions the world has seen in recent times took place in the Port of Beirut. Caused by the detonation of 2,750 tons of ammonium nitrate, inadequate stored in a warehouse in the port, the blast destroyed much of the city’s port and the surrounding infrastructure and severly  damaged the dense residential and commercial areas within 5 km of the explosion site. The impact of the explosion, which registered as a 3.3 magnitude earthquake according to the U.S. Geological Survey, was felt as far away as the island of Cyprus.</p><p>Athough the event was an technological hazard, the impact of the explosion is similar to a standardised natural disaster.</p><p>According to UNDP, a total of 200 000 residential units were affected with an estimated of 40 000 buildings damaged; 200 people lost their lives, around 6 000 individuals were injuried and around 300 000 people were displaced.</p><p>Such figure are comparable to other large-scale disasters such as Cyclone Vayu in India, which occured in June 2019 or the displacement caused by the Typhoon Vongfong, in the Philippines.</p><p>The frequent increase of the natural disasters  puts pressure on the critical infrastructure of the cities. The disruption of the transportation system,  which is vital for the sustainable daily operations, are having a big impact on the economical, enviromental and social dimension of a city system. Among the various types of transportation system, ports are a focal point because of its strategic role for the economic growth of cities,regions and  global network. In addition, they are nodal points for the social and economical activity of the inhabitants.</p><p>Although the ports have played a key role in the development of their host cities, they are also vulnerable to a broad range of risks and threats because of a particular spatial character: the location at the intersection of land and sea.  </p><p>The study of the Beirut’s Port explosion examines the impact of port failures on the host urban enviroment and the relationship between hazards, vulnerability and the impact. The vulnerability of the port to disasters results  to the vulnerability of its host city. A context –based understanding  of the impact of the disaster and the elements at risk is essential to identify appropriate risk management strategies. The location of the port within the urban environment, in densely populated area, as in case of Beirut are some of the characteristics of the port cities that can magnify the impact of disasters to which they are prone.  The study will focus on a collection of data that records the impact and allows visualisation of the complex patterns of the disaster risk reduction.</p><p>The impact caused by the Beirut’s port explosion reminds us about the important role of the ports in their host cities and how fundamental is to identify the port’s infrastructure  exposure to hazards and risks.  Lessons learned from such event may be useful to reduce disaster risks in the port cities.</p>

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