A Field Investigation on the Effects of Using USPs in Transition Zone From Ballasted Track to Bridges

2019 ◽  
Vol 17 (9) ◽  
pp. 1421-1431 ◽  
Author(s):  
Jaber Mottahed ◽  
Jabbar Ali Zakeri ◽  
Saeed Mohammadzadeh
Keyword(s):  
Transition Zone ◽  
Field Investigation ◽  
Ballasted Track

A new field investigation on the lateral and longitudinal resistance of ballasted track

2018 ◽  
Vol 232 (8) ◽  
pp. 2138-2148 ◽  
Author(s):  
Saeed Mohammadzadeh ◽  
Morteza Esmaeili ◽  
Fatemeh Khatibi
Keyword(s):  
Field Study ◽  
Field Investigation ◽  
Test Track ◽  
Lateral Resistance ◽  
Longitudinal Stiffness ◽  
Wide Range ◽  
Ballasted Track ◽  
Good Consistency ◽  
Southwest Region ◽  
Longitudinal Resistance

Track buckling is a complicated phenomenon that is caused by a wide range of parameters including the nature of track loading and the lateral and longitudinal resistance of a track. In this paper, the results of a field study on a test track in the Aprin railway station (in the southwest region of Tehran city) are presented to investigate the lateral and longitudinal resistance of the ballasted track. The lateral resistance of the track is measured by using both the single tie (sleeper) push test and the sleeper lateral pull test, and the results of the two methods are found to be compatible. The contributions of the ballast shoulder, crib, and the base part in the total lateral resistance are obtained for the loose and compacted ballast conditions, which showed good consistency with the presented data of literature. The longitudinal resistance is measured by using an innovative setup prepared on the test track. The measured longitudinal stiffness per sleeper is approximately twice of what was measured in the previous studies on track panels. The measured longitudinal stiffness during the unloading process is found to be 40% of the loading stiffness.

scholarly journals Delimitation of the transition zone between active and inactive gully erosion in the Chinese Loess Plateau

2018 ◽  
Author(s):  
Jilong Li ◽  
Guoan Tang ◽  
Fayuan Li ◽  
Jianjun Cao
Keyword(s):  
Transition Zone ◽  
Loess Plateau ◽  
Spatial Location ◽  
Field Investigation ◽  
Gully Erosion ◽  
Chinese Loess Plateau ◽  
Visual Interpretation ◽  
Chinese Loess ◽  
Spatial Differences ◽  
Definition Of

The interaction of various erosivities is the main factor that causes significant spatial differences in the gully development of the Loess Plateau. In some areas of the western Loess Plateau, the accumulation process is greater than erosion process, most of the gullies are in an inactive state while the loess gullies in the east is eroded with a high degree of active development. From the view of the geographical system boundary, there must be a transition zone with in the process of activity of loess gully erosion. In view of this geographical phenomenon, the definition of the erosion-active and erosion-inactive loess gully is given firstly, and then the objective existence of the transition zone is demonstrated. Based on the field investigation data and corresponding remote sensing images, the characteristic system of active and inactive loess gully is constructed. Combining the data of 1: 1000000 geomorphological map and 1: 10000 standard mapsheet of China, the loess erosionactive and erosion-inactive loess gully are identified by visual interpretation method, and the spatial location and trend of the transition zone are determined. The results show that the boundary is essentially a complex transition zone, and the core part is located in the middle of the Longxi Loess Plateau. The development characteristics of loess gullies in the transition zone and on both sides are also analyzed from the aspects of geology, natural environment and climate.

scholarly journals Delimitation of the transition zone between active and inactive gully erosion in the Chinese Loess Plateau

2018 ◽  
Author(s):  
Jilong Li ◽  
Guoan Tang ◽  
Fayuan Li ◽  
Jianjun Cao
Keyword(s):  
Transition Zone ◽  
Loess Plateau ◽  
Spatial Location ◽  
Field Investigation ◽  
Gully Erosion ◽  
Chinese Loess Plateau ◽  
Visual Interpretation ◽  
Chinese Loess ◽  
Spatial Differences ◽  
Definition Of

The interaction of various erosivities is the main factor that causes significant spatial differences in the gully development of the Loess Plateau. In some areas of the western Loess Plateau, the accumulation process is greater than erosion process, most of the gullies are in an inactive state while the loess gullies in the east is eroded with a high degree of active development. From the view of the geographical system boundary, there must be a transition zone with in the process of activity of loess gully erosion. In view of this geographical phenomenon, the definition of the erosion-active and erosion-inactive loess gully is given firstly, and then the objective existence of the transition zone is demonstrated. Based on the field investigation data and corresponding remote sensing images, the characteristic system of active and inactive loess gully is constructed. Combining the data of 1: 1000000 geomorphological map and 1: 10000 standard mapsheet of China, the loess erosionactive and erosion-inactive loess gully are identified by visual interpretation method, and the spatial location and trend of the transition zone are determined. The results show that the boundary is essentially a complex transition zone, and the core part is located in the middle of the Longxi Loess Plateau. The development characteristics of loess gullies in the transition zone and on both sides are also analyzed from the aspects of geology, natural environment and climate.

Field study using additional rails and an approach slab as a transition zone from slab track to the ballasted track

2017 ◽  
Vol 232 (4) ◽  
pp. 970-978 ◽  
Author(s):  
H Heydari-Noghabi ◽  
JA Zakeri ◽  
M Esmaeili ◽  
JN Varandas
Keyword(s):  
Transition Zone ◽  
Dynamic Behavior ◽  
Field Tests ◽  
Field Measurements ◽  
Sudden Increase ◽  
Transition Zones ◽  
Slab Track ◽  
Railway Line ◽  
Approach Slab ◽  
Ballasted Track

An abrupt change in the stiffness of railway tracks at the junction between slab track and ballasted track causes increased dynamic loads, asymmetric settlements, damage of track components, and, consequently, increased maintenance costs. Due to this, a transition zone is usually built at the junction between the ballasted and the ballastless tracks to reduce the aforementioned problems. One of the methods suggested as a transition zone in these areas is to use a combination of an approach slab and additional rails. This study evaluates the dynamic behavior of this type of transition zone using field tests and also compares its performance with a transition zone built only with an approach slab. Hence, in the Tehran–Karaj railway line, two types of transition zones were constructed: one including only the approach slab and the other one including additional rails and an approach slab. Then, by conducting some field tests, the dynamic behavior of the track in these two types of transition zones was examined. The results of the field measurements show that for the analyzed case study, at the combined transition zone with additional rails and an approach slab, instead of a sudden increase in rail displacements from the slab track to the ballasted track (i.e. by 53%), initially, in the first part of the transition zone (with additional rails and an approach slab), the deflections increase by an average of 31%, and then in the second part of the transition zone (with additional rails only) the deflections increase additionally by 11%.

Weekly Exercise Consistently Reinstates Positive Mood

1998 ◽  
Vol 3 (4) ◽  
pp. 271-280 ◽  
Author(s):  
Hannah Steinberg ◽  
Briony R. Nicholls ◽  
Elizabeth A. Sykes ◽  
N. LeBoutillier ◽  
Nerina Ramlakhan ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Negative Mood ◽  
Real Life ◽  
Positive Mood ◽  
Field Investigation ◽  
Single Bout ◽  
Before And After ◽  
Exercise Class ◽  
Negative Feelings ◽  
Over Time

Mood improvement immediately after a single bout of exercise is well documented, but less is known about successive and longer term effects. In a “real-life” field investigation, four kinds of exercise class (Beginners, Advanced, Body Funk and Callanetics) met once a week for up to 7 weeks. Before and after each class the members assessed how they felt by completing a questionnaire listing equal numbers of “positive” and “negative” mood words. Subjects who had attended at least five times were included in the analysis, which led to groups consisting of 18, 20, 16, and 16 subjects, respectively. All four kinds of exercise significantly increased positive and decreased negative feelings, and this result was surprisingly consistent in successive weeks. However, exercise seemed to have a much greater effect on positive than on negative moods. The favorable moods induced by each class seemed to have worn off by the following week, to be reinstated by the class itself. In the Callanetics class, positive mood also improved significantly over time. The Callanetics class involved “slower,” more demanding exercises, not always done to music. The Callanetics and Advanced classes also showed significantly greater preexercise negative moods in the first three sessions. However, these differences disappeared following exercise. Possibly, these two groups had become more “tolerant” to the mood-enhancing effects of physical exercise; this may be in part have been due to “exercise addiction.”

Production of asari (Manila) clams, Ruditapes philippinarum, during the period of harvest decrease in the 2000s in the Banzu tidal area, Tokyo Bay

2020 ◽  
Vol 33 ◽  
pp. 14
Author(s):  
Mitsuharu Toba ◽  
Jun Kakino ◽  
Kazuo Tada ◽  
Yutaka Kobayashi ◽  
Hideharu Tsuchie
Keyword(s):  
Field Investigation ◽  
Ruditapes Philippinarum ◽  
Management Style ◽  
Seed Stock ◽  
Tokyo Bay ◽  
Yearly Variation ◽  
Culture Area ◽  
Stock Biomass ◽  
Tidal Area ◽  
High Level

In Tokyo Bay, the harvestable quantity of asari (Manila) clams Ruditapes philippinarum has been decreasing since the late 1990s. We conducted a field investigation on clam density in the Banzu culture area from April 1988 to December 2014 and collected records spanning January 1986 to September 2017 from relevant fisheries cooperative associations to clarify the relationship between the temporal variation in stock abundance and the production activities of fishermen. The yearly variation in clam abundance over the study period was marked by larger decreases in the numbers of larger clams. A large quantity of juvenile clams, beyond the biological productivity of the culture area, may have been introduced as seed stock in the late 1980s despite the high level of harvestable stock. The declines in harvested quantity began in the late 1990s and may have been caused by decreases in harvestable stock despite the continuous addition of seed stock clams. The harvested quantity is likely to be significantly dependent upon the wild clam population, even within the culture area, as the harvestable quantity was not correlated with the quantity of seed stock introduced during the study period. These declines in harvested quantity may have resulted from a decreasing number of operating harvesters due to the low level of harvestable stock and consequently reduced profitability. Two findings were emphasized. A certain management style, based on predictions of the contributions of wild and introduced clams to future stock biomass, is essential for economically-feasible culturing. In areas with less harvestable stock, actions should be taken to maintain the incomes of harvesters while avoiding overexploitation, even if the total harvest quantity decreases.

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