Research of the influence of the dissipation parameter of the elastic element of the side bearings of the bogies the parameters of the motion of the freight car

2021 ◽  
Author(s):  
Aleksey Nikolaevich Davydov
Keyword(s):  
Elastic Element ◽  
Dissipation Parameter ◽  
Freight Car

A Study of Driving evaluation factors for Introducing UBI to freight car

2016 ◽  
Author(s):  
GeomGeun Yoo ◽  
◽  
Jong-Un Won ◽  
YongJang Kwon ◽  
Jaewon Kim ◽  
...  
Keyword(s):  
Freight Car

scholarly journals Contractile behavior of the gastrocnemius medialis muscle during running in simulated hypogravity

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Charlotte Richter ◽  
Bjoern Braunstein ◽  
Benjamin Staeudle ◽  
Julia Attias ◽  
Alexander Suess ◽  
...  
Keyword(s):  
Elastic Element ◽  
Muscle Wasting ◽  
Space Station ◽  
Vigorous Exercise ◽  
Gastrocnemius Medialis ◽  
Gravitational Forces ◽  
Series Elastic Element ◽  
Applied Loading ◽  
Exercise Countermeasures ◽  
Series Elastic

AbstractVigorous exercise countermeasures in microgravity can largely attenuate muscular degeneration, albeit the extent of applied loading is key for the extent of muscle wasting. Running on the International Space Station is usually performed with maximum loads of 70% body weight (0.7 g). However, it has not been investigated how the reduced musculoskeletal loading affects muscle and series elastic element dynamics, and thereby force and power generation. Therefore, this study examined the effects of running on the vertical treadmill facility, a ground-based analog, at simulated 0.7 g on gastrocnemius medialis contractile behavior. The results reveal that fascicle−series elastic element behavior differs between simulated hypogravity and 1 g running. Whilst shorter peak series elastic element lengths at simulated 0.7 g appear to be the result of lower muscular and gravitational forces acting on it, increased fascicle lengths and decreased velocities could not be anticipated, but may inform the development of optimized running training in hypogravity. However, whether the alterations in contractile behavior precipitate musculoskeletal degeneration warrants further study.

A Method of Obtaining Detailed Freight Car Truck Loading Data

1980 ◽  
Vol 102 (2) ◽  
pp. 151-158
Author(s):  
C. P. Spencer ◽  
T. L. Pitchford
Keyword(s):  
Load Cell ◽  
Vertical Load ◽  
Car Body ◽  
Service Testing ◽  
Sample Data ◽  
Actual Service ◽  
Truck Loading ◽  
Freight Car

A method of obtaining freight car truck loading data utilizing a strain gaged truck bolster as a load cell is described. Analysis necessary to derive both the magnitude and location of the line of action of the freight car body vertical load resultant is presented. Techniques for cycle counting applicable to fatigue studies are suggested. Sample data from actual service testing are presented.

A statistical study of precursor activity in rain-induced landslides

2014 ◽  
Vol 23 (3-4) ◽  
pp. 79-86 ◽  
Author(s):  
Markos Avlonitis ◽  
George Efremidis ◽  
Avraam Konstantinidis
Keyword(s):  
Structural Heterogeneity ◽  
Material Behavior ◽  
Failure Plane ◽  
Power Law Distribution ◽  
Dissipation Parameter ◽  
Deformation Processes ◽  
Precautionary Measures ◽  
Weak Plane ◽  
Block Models ◽  
Precursor Activity

AbstractSpring-block models were introduced several years ago to model avalanche-like dynamics for catastrophic landslides. This article aims to address precursor phenomena in rain-induced landslides through the enrichment of a two-dimensional spring-block model with displacement gradients and stochasticity. This approach is along the lines of Aifantis and coworkers, who introduced deterministic gradients to stabilize material behavior in the softening regime and later expanded on it by introducing stochastic terms to model the competition between deterministic gradients and random effects. To this end, an appropriate stochastic constitutive relation, introducing an effective dissipation parameter (which is related to structural heterogeneity and deformation processes at the failure plane) is used. It is shown that there is definite precursor activity before rain-induced landslides that can be modeled by a process of material yielding at the failure plane (a “weak” plane at a certain depth, parallel to the surface of the soil or rock mass, over which landslide takes place). This activity is related to the exponent b of the power-law distribution of the slip events within the failure plane. Cellular automaton simulations were used to verify the analytical predictions, which can be useful to geoscientists and engineers, as an early prediction of the initiation of a landslide can minimize its catastrophic results through proper safety and precautionary measures.

The Effect of Deformation on Mechanical Properties and Shakedown on Railroad Wheels

2014 ◽  
Author(s):  
Steven L. Dedmon ◽  
Takashi Fujimura ◽  
Daniel Stone
Keyword(s):  
Mechanical Properties ◽  
Rolling Contact ◽  
Effect Of Temperature ◽  
Plastic Deformations ◽  
Rail Head ◽  
Class D ◽  
Shakedown Theory ◽  
Freight Car ◽  
Class C ◽  
Railroad Wheels

Plastic deformations alter the mechanical properties of many metals and alloys. Class C and Class D wheel steels such as are used in North American freight car service are particularly affected by plastic deformations occurring during rolling contact between the wheel tread and rail head. This investigation determines the effect plastic deformations have on the mechanical properties of Class C and D wheel steels and how those changes could relate to shakedown theory. The effect of temperature is also discussed.

ASSESSMENT AND FORECASTING OF FREIGHT CAR TECHNICAL STATE

2021 ◽  
Vol 2021 (5) ◽  
pp. 40-47
Author(s):  
Elena Rozhkova
Keyword(s):  
Graphical Model ◽  
Technical State ◽  
Distribution Law ◽  
Repair Service ◽  
Statistic Modeling ◽  
Average Operating ◽  
Freight Car ◽  
Run Up ◽  
Definition Of ◽  
The Given

The purpose of this work is the assessment and forecasting of freight car technical state at life stages. The scientific novelty consists in the definition of car operating run-up to the first failure and between failures, and also in the definition of car life to considerable repair fulfillment from the operating run between failures and development of a graphical model of freight car reliability. As a result of the statistic modeling of gondola car operating runs up to the first failure it is defined that the given random value conforms to a normal distribution law, the first car setoff in TOR due to wear failure takes place at the operating run of 85,000 km. Besides the operating run-up to the first failure there was defined an operating run-up between failures. It is proved that the operating run-up between failures conforms to the exponential law of distribution, the mathematical expectation of which is 13,000 km. The results of investigations mentioned above formed the basis of the graphical model of car reliability. An inter-repair service life of a car can be represented as a sum of the following operating run-ups: operating run-ups to the first failure, the product of operating run-ups between failures and the number of failures and a residual operating run-up (from the utmost current repair to the nearest scheduled repair). On the basis of the mentioned it is expedient to consider a technology for the realization of an enlarged repair with the purpose of the repetition exclusion in car setoffs during the inter-repair term. On the basis of the simulator there is obtained the dependence of the frequency of car enlarged current repair fulfillment depending on average operating run-up between failures. At present an enlarged current repair must be carried out only for gondola cars in the planned order after having reached 80,000 km. The repair mentioned can be carried out both under depot conditions, and under conditions of repair workshops. The advantage of such a system of repair consists in the increase car work reliability during the inter-repair term.

Sign in / Sign up

Export Citation Format

Share Document