Estimation and Analysis of the Tire Pressure Effects on the Comportment of the Vehicle Center of Gravity

Truck tire inflation pressure plays an important role in the tire–pavement interaction process. As a conventional approximation method in many pavement studies, tire–pavement contact stress is frequently assumed to be uniformly distributed over a circular contact area and to be simply equal to the tire pressure. However, recent studies have demonstrated that the tire–pavement contact stress is far from uniformly distributed. Measured tire–pavement contact stress data were input into an elastic multilayer pavement analysis program to compute pavement immediate responses. Two asphalt concrete pavement structures, a thick pavement and a thin pavement, were investigated. Major pavement responses at locations in the pavement structures were computed with the measured tire–pavement contact stress data and were compared with the conventional method. The computation results showed that the conventional method tends to underestimate pavement responses at low tire pressures and to overestimate pavement responses at high tire pressures. A two-way analysis of variance model was used to compare the pavement responses to identify the effects of truck tire pressure on immediate pavement responses. Statistical analysis found that tire pressure was significantly related to tensile strains at the bottom of the asphalt concrete layer and stresses near the pavement surface for both the thick and thin pavement structures. However, tire pressure effects on vertical strain at the top of the subgrade were minor, especially in the thick pavement.

Download Full-text

Load, Speed, and Pressure Effects on Passenger Car Tire Rolling-Loss Distribution

Rubber Chemistry and Technology ◽

10.5254/1.3536212 ◽

1988 ◽

Vol 61 (4) ◽

pp. 669-687 ◽

Cited By ~ 1

Author(s):

D. J. Schuring ◽

J. D. Clark

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Pressure Effects ◽

The Other ◽

Model Output ◽

Tire Pressure ◽

Loss Distribution ◽

Analysis Techniques ◽

The Heat Transfer Coefficient ◽

Made In

Abstract The procedure explained in this paper permits calculation of individual tire region contributions to rolling loss without altering the tire. Many different tire-build configurations can be considered using this technique. Different belt, bead, and subtread materials' contributions to rolling-loss distribution can be studied; different tire shapes and thicknesses can be considered. Only a single tire of each configuration need be built, and it can be retested if necessary. Results obtained here show that the tread region of the tire tested behaves differently than the other regions. Changes in tire pressure, load, and speed lead to changes in the remaining individual tire regions' contributions that are in the same direction as the overall tire loss. A tire design that is altered to accommodate new specifications may lead to an increase in rolling loss that is greater than some designated value. An analysis of the type presented here may show which region of the new tire design should be changed to bring the loss within desired limits. The heat-transfer coefficient of the tire in this model is a linear function of velocity, independent of tire load and pressure. We have confidence in this relation as the model results are derived from both loss measurements and tire surface temperature measurements made in the laboratory. The model output is based on fundamental heat-transfer precepts and treated mathematically by established analysis techniques.

Download Full-text

High Aircraft Tire Pressure Effects on HMA Airfield Pavements

RILEM Bookseries - 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials ◽

10.1007/978-94-017-7342-3_66 ◽

2015 ◽

pp. 825-836 ◽

Cited By ~ 1

Author(s):

Navneet Garg ◽

Qiang Li ◽

Monir Haggag

Keyword(s):

Pressure Effects ◽

Tire Pressure

Download Full-text

Reduction in Pain Sensitivity from Pharmacological Elevation of Blood Pressure in Persons with Chronically Low Blood Pressure

Journal of Psychophysiology ◽

10.1027/0269-8803.23.3.104 ◽

2009 ◽

Vol 23 (3) ◽

pp. 104-112 ◽

Cited By ~ 12

Author(s):

Stefan Duschek ◽

Heike Heiss ◽

Boriana Buechner ◽

Rainer Schandry

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Pain Sensitivity ◽

Pain Threshold ◽

Pain Perception ◽

Drug Effects ◽

Pressure Effects ◽

Double Blind ◽

Low Blood Pressure ◽

Present Trial

Recent studies have revealed evidence for increased pain sensitivity in individuals with chronically low blood pressure. The present trial explored whether pain sensitivity can be reduced by pharmacological elevation of blood pressure. Effects of the sympathomimetic midodrine on threshold and tolerance to heat pain were examined in 52 hypotensive persons (mean blood pressure 96/61 mmHg) based on a randomized, placebo-controlled, double-blind design. Heat stimuli were applied to the forearm via a contact thermode. Confounding of drug effects on pain perception with changes in skin temperature, temperature sensitivity, and mood were statistically controlled for. Compared to placebo, higher pain threshold and tolerance, increased blood pressure, as well as reduced heart rate were observed under the sympathomimetic condition. Increases in systolic blood pressure between points of measurement correlated positively with increases in pain threshold and tolerance, and decreases in heart rate were associated with increases in pain threshold. The findings underline the causal role of hypotension in the augmented pain sensitivity related to this condition. Pain reduction as a function of heart rate decrease suggests involvement of a baroreceptor-related mechanism in the pain attrition. The increased proneness of persons with chronic hypotension toward clinical pain is discussed.

Download Full-text

Center of gravity

AccessScience ◽

10.1036/1097-8542.118800 ◽

2015 ◽

Keyword(s):

Center Of Gravity

Download Full-text

Blood pressure effects on memory retrieval: The normative aging study

PsycEXTRA Dataset ◽

10.1037/e525402008-001 ◽

2008 ◽

Author(s):

Shelley Amberg ◽

Christopher B. Brady ◽

Avron Spiro

Keyword(s):

Blood Pressure ◽

Memory Retrieval ◽

Pressure Effects ◽

Normative Aging Study ◽

Aging Study ◽

Blood Pressure Effects ◽

Normative Aging

Download Full-text

ALLOYING AND PRESSURE EFFECTS ON THE MAGNETIC PROPERTIES OF CeNi

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19888326 ◽

1988 ◽

Vol 49 (C8) ◽

pp. C8-719-C8-720

Author(s):

D. Gignoux ◽

J. C. Gomez Sal ◽

J. Rodriguez Fernandez ◽

J. Voiron

Keyword(s):

Magnetic Properties ◽

Pressure Effects

Download Full-text

Classification of Acceleration Waveforms during Walking by Wavelet Transform

Methods of Information in Medicine ◽

10.1055/s-0038-1636855 ◽

1997 ◽

Vol 36 (04/05) ◽

pp. 356-359 ◽

Cited By ~ 27

Author(s):

M. Sekine ◽

M. Ogawa ◽

T. Togawa ◽

Y. Fukui ◽

T. Tamura

Keyword(s):

Wavelet Transform ◽

Wavelet Analysis ◽

Center Of Gravity ◽

Dynamic Responses ◽

Sequential Data ◽

Acceleration Signal ◽

Continuous Dynamic

Abstract:In this study we have attempted to classify the acceleration signal, while walking both at horizontal level, and upstairs and downstairs, using wavelet analysis. The acceleration signal close to the body’s center of gravity was measured while the subjects walked in a corridor and up and down a stairway. The data for four steps were analyzed and the Daubecies 3 wavelet transform was applied to the sequential data. The variables to be discriminated were the waveforms related to levels -4 and -5. The sum of the square values at each step was compared at levels -4 and -5. Downstairs walking could be discriminated from other types of walking, showing the largest value for level -5. Walking at horizontal level was compared with upstairs walking for level -4. It was possible to discriminate the continuous dynamic responses to walking by the wavelet transform.

Download Full-text