Vibration Control Design for Light Rail Transit: A Single Project With the Full Rainbow of Vibration Control Features: Case Study

2015 ◽  
Author(s):  
Rob Greene
Keyword(s):  
United States ◽  
Vibration Control ◽  
Single Layer ◽  
The United States ◽  
Light Rail ◽  
Rail Transit ◽  
Control Approach ◽  
Slab Track ◽  
Rail System ◽  
Under Construction

Because of the recent emphasis on rail transit infrastructure expansion and rebuilding in the United States, there is concern about the potential adverse vibration effects on existing activities that are sensitive to vibration and ground-borne-noise located in proximity to new or reactivated rail system rights-of-way. A Southern California at-grade/elevated LRT system that is currently under construction required the design and specification of extensive vibration control features. The final design needed to include the entire range of vibration mitigation tools presented in the Federal Transit Administration guidance manual. Designs and Contract Specifications included simple single-layer ballast mats; multi-layer ballast mats; high-resilience direct fixation fasteners; potential wheel-squeal solutions; low-vibration special trackwork; continuously-supported, street-running, floating slab track; and discrete, steel-helical-spring-supported floating slab track. It is noteworthy that the discrete steel-spring-supported FST is the first use of this vibration control approach in an at-grade rail system in the United States. This paper will discuss the overall approach, data analysis, solutions development, and the final designs prepared for this project and how this information may be beneficial to other projects with similar issues.

A Case Study of Planning

2001 ◽  
Author(s):  
Marlon Boarnet ◽  
Randall C. Crane
Keyword(s):  
United States ◽  
Land Use ◽  
Urban Areas ◽  
San Diego ◽  
The United States ◽  
San Diego County ◽  
Light Rail ◽  
Rail Transit ◽  
The South

The facts, figures, and inferences in chapter 7 regarding municipal behavior toward transit-oriented housing opportunities illustrate many points. Still, there is much that even a careful statistical analysis might miss or misunderstand. For that reason, we also explored what we could learn by talking to real planners about these issues. The case of San Diego is interesting and useful for several reasons. First, the San Diego Trolley is the oldest of the current generation of light rail projects in the United States. Unlike many newer systems, the age of San Diego’s rail transit (the South Line opened in 1981) allows time for land use planning to respond to the fixed investment. Second, the San Diego system is no stranger to modern transit-based planning ideas. The San Diego City Council approved a land-use plan for their stations that includes many of the ideas promoted by transit-oriented development (TOD) advocates (City of San Diego, 1992). Third, the light rail transit (LRT) authority in San Diego County, the Metropolitan Transit Development Board (MTDB), is often regarded as one of the more successful municipal LRT agencies. The initial parts of the MTDB rail transit system were constructed strictly with state and local funds, using readily available, relatively low-cost technology (Demoro and Harder, 1989, p. 6). Portions of San Diego’s system have high fare-box recovery rates, including the South Line, which in its early years recovered as much as 90 percent of operating costs at the fare box (Gómez-Ibáñez, 1985). All of these factors make San Diego potentially a “best-case” example of TOD implementation. When generalizing from this case study, it is important to remember that the transit station area development process in San Diego is likely better developed than in many other urban areas in the United States. The results from San Diego County can illustrate general issues that, if they have not already been encountered, might soon become important in other urban areas with rail transit systems. Also, given San Diego County’s longer history of both LRT and TOD when compared with most other regions, any barriers identified in San Diego County might be even more important elsewhere.

scholarly journals The Color of Health: Residential Segregation, Light Rail Transit Developments, and Gentrification in the United States

2019 ◽  
Vol 16 (19) ◽  
pp. 3683 ◽  
Author(s):  
Shadi O. Tehrani ◽  
Shuling J. Wu ◽  
Jennifer D. Roberts
Keyword(s):  
United States ◽  
Residential Segregation ◽  
Low Income ◽  
Traffic Congestion ◽  
The United States ◽  
Careful Consideration ◽  
Light Rail ◽  
Rail Transit ◽  
Light Rail Transit ◽  
Transit Oriented Development

As the modern urban–suburban context becomes increasingly problematic with traffic congestion, air pollution, and increased cost of living, city planners are turning their attention to transit-oriented development as a strategy to promote healthy communities. Transit-oriented developments bring valuable resources and improvements in infrastructure, but they also may be reinforcing decades-old processes of residential segregation, gentrification, and displacement of low-income residents and communities of color. Careful consideration of zoning, neighborhood design, and affordability is vital to mitigating the impacts of transit-induced gentrification, a socioeconomic by-product of transit-oriented development whereby the provision of transit service “upscales” nearby neighborhood(s) and displaces existing community members with more affluent and often White residents. To date, the available research and, thus, overall understanding of transit-induced gentrification and the related social determinants of health are limited and mixed. In this review, an overview of racial residential segregation, light rail transit developments, and gentrification in the United States has been provided. Implications for future transit-oriented developments are also presented along with a discussion of possible solutions.

Light rail transit in the United States

1980 ◽  
Vol 9 (1) ◽  
pp. 67-74
Author(s):  
Stewart F. Taylor
Keyword(s):  
United States ◽  
The United States ◽  
Light Rail ◽  
Rail Transit ◽  
Light Rail Transit

Corrosion Control of Modern Light Rail Transit (LRT) Systems

2017 ◽  
Author(s):  
Michael Berman ◽  
Quentin P. Williams
Keyword(s):  
United States ◽  
The United States ◽  
Control Measures ◽  
Light Rail ◽  
Rail Transit ◽  
National Bureau ◽  
Light Rail Transit ◽  
Corrosion Control ◽  
Transit System ◽  
Transit Systems

Since the introduction of electrified transit systems in the United States there has been a number of advancements in the field of corrosion control related to light rail transit (LRT) systems. Modern day direct current (dc) powered LRT systems have been designed with a variety of corrosion control features built-in. Most of the research into corrosion control and the mitigation of stray currents known as electrolysis in the early days of electrified transit systems first appeared extensively in papers prepared and presented by personnel of the National Bureau of Standards. This research has led to better protection against corrosion of transit systems and nearby structures throughout the years. Due to the ever increasing number of transit systems being built or upgraded, it’s essential to incorporate the installation, testing and monitoring of corrosion control measures in these transit systems. By integrating these corrosion control features into the design of LRT systems and subsystems, it will help to prevent premature corrosion failures on LRT fixed facilities and other structures. This paper identifies the main causes of corrosion and how corrosion control can be implemented into the design of LRT systems to prevent damage to the transit system and other structures.

scholarly journals Analysis of the Implementation of the South Sumatra Transit Light Rail Slab Track

2017 ◽  
Vol 1 (2) ◽  
pp. 151-158
Author(s):  
Sachiko Mawaddah Lestari ◽  
Muhammad Fauzan
Keyword(s):  
Road Construction ◽  
Light Rail ◽  
Rail Transit ◽  
Light Rail Transit ◽  
The South ◽  
Slab Track ◽  
The Republic ◽  
The Government ◽  
Under Construction ◽  
Elevated Road

Transportation has an important role in supporting economic growth, development and unifying the territory of the Unitary Republic of Indonesia, in order to improve transportation services in supporting development in South Sumatra Province, and supporting the implementation of the 2018 Asian Games, it is necessary to accelerate the implementation of Light Rail Transit in the province of South Sumatra. This is related to the Republic of Indonesia's Presidential Regulation Number 116 of 2015 concerning the Acceleration of the Operation of Light Rail Transit in South Sumatra Province. At the railroad track in Indonesia there is currently no railroad that has operated using the slab track construction but at this time the Government of Indonesia is conducting railroad construction in Indonesia on a national scale. In the construction of the South Sumatra LRT (Light Rail Transit) is a power railroad construction electricity that is in the process of development that will use modern railroad construction that is using slab track construction. In this very happy opportunity the writer got the opportunity to do research at the South Sumatra LRT Work Unit because the South Sumatra LRT is under construction. South Sumatra LRT uses elevated road construction using slab track construction. At present the South Sumatra LRT is the first project to undertake slab track construction in Indonesia. In fact, there is no railroad in Indonesia that operates using slab track construction.

Rapid Rail Transit and Tourism Development in the United States

2011 ◽  
Vol 13 (3) ◽  
pp. 381-397 ◽  
Author(s):  
Cherylynn Becker ◽  
Babu P. George
Keyword(s):  
United States ◽  
Tourism Development ◽  
The United States ◽  
Rail Transit

Design and Construction of the New Staten Island Ferries

1979 ◽  
Vol 16 (04) ◽  
pp. 365-380
Author(s):  
Edward J. Ciechon ◽  
Larry N. Hairston
Keyword(s):  
United States ◽  
The United States ◽  
Staten Island ◽  
Under Construction ◽  
Propulsion Concept ◽  
Design And Construction

Although cycloidal propulsion is well known and has been widely accepted in European service for many years, its applications in the United States are relatively rare. The reasons for selecting this unique propulsion concept for the two new ferries now under construction for Manhattan-Staten Island service are described in this paper, as well as the design and construction problems encountered.

Cryptic Wolbachia (Rickettsiales: Rickettsiaceae) Detection and Prevalence in Culicoides (Diptera: Ceratopogonidae) Midge Populations in the United States

2020 ◽  
Vol 57 (4) ◽  
pp. 1262-1269 ◽  
Author(s):  
Hunter Covey ◽  
Rafe H Hall ◽  
Alyssa Krafsur ◽  
Megan L Matthews ◽  
Phillip T Shults ◽  
...  
Keyword(s):  
United States ◽  
Vector Control ◽  
Disease Transmission ◽  
The United States ◽  
Hemorrhagic Disease ◽  
Human Pathogens ◽  
Control Approach ◽  
16S Gene ◽  
Culicoides Sonorensis

Abstract Culicoides midges vector numerous veterinary and human pathogens. Many of these diseases lack effective therapeutic treatments or vaccines to limit transmission. The only effective approach to limit disease transmission is vector control. However, current vector control for Culicoides midges is complicated by the biology of many Culicoides species and is not always effective at reducing midge populations and impacting disease transmission. The endosymbiont Wolbachia pipientis Hertig may offer an alternative control approach to limit disease transmission and affect Culicoides populations. Here the detection of Wolbachia infections in nine species of Culicoides midges is reported. Infections were detected at low densities using qPCR. Wolbachia infections were confirmed with the sequencing of a partial region of the 16S gene. Fluorescence in situ hybridization of Culicoides sonorensis Wirth and Jones adults and dissected ovaries confirm the presence of Wolbachia infections in an important vector of Bluetongue and Epizootic hemorrhagic disease viruses. The presence of Wolbachia in Culicoides populations in the United States suggests the need for further investigation of Wolbachia as a strategy to limit transmission of diseases vectored by Culicoides midges.

Attention Deficit/Hyperactivity Disorder: Diagnosis and Stereotypy

2015 ◽  
Vol 17 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Stewart Justman
Keyword(s):  
United States ◽  
Attention Deficit Hyperactivity Disorder ◽  
Attention Deficit ◽  
Attention Deficit Disorder ◽  
Sense Of Self ◽  
The United States ◽  
Hyperactivity Disorder ◽  
Diagnostic And Statistical Manual ◽  
Relative Rarity ◽  
Under Construction

The official symptoms of attention deficit disorder and attention deficit/hyperactivity disorder (ADHD) as first codified in the 3rd edition of the Diagnostic and Statistical Manual of Mental Disorders bear an uneasy resemblance to potent caricatures of Blacks that had long been in circulation in the United States. In effect, traits such as laziness and troublesomeness persistently associated with Blacks became symptoms that could be had by anyone, Black, White, or other. But just as racial imagery plays on stereotypes, the ADHD diagnosis itself has become a stereotype. Only stereotyped figures have the telltale marks of identity that children with ADHD are said to have. As we have known at least since the time of the prejudice studies cited by the United States Supreme Court in 1954, stereotypes can be highly injurious, especially if they are internalized by their objects. Children who grow with the diagnosis of ADHD, incorporating it into their sense of self even while it is under construction, may well internalize its messages. That in turn may have something to do with the dismal long-term outcomes of ADHD despite the relative rarity of severe cases.

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