Undrained limiting pressure behind soil gaps in contiguous pile walls

The influence of the pressure of oxygen on the rate of oxidation of copper has been studied by earlier workers. Pilling and Bedworth working at 800°C. found that the rate of oxidation continued constant as the pressure was decreased until the pressure reached 0·3 mm. Berger found a limiting pressure of 100 mm. Hinshelwood’s work makes it clear that for activated copper at 305°C. the limiting pressure is greater than 5 mm. Palmer obtained a value of about 300 mm. The object of this work was to investigate more closely the significance of the limiting pressure.

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Limiting pressure on a laterally loaded pile in a frictional soil

Géotechnique Letters ◽

10.1680/geolett.12.00007 ◽

2012 ◽

Vol 2 (2) ◽

pp. 55-60 ◽

Cited By ~ 10

Author(s):

D. Pan ◽

J. A. Smethurst ◽

W. Powrie

Keyword(s):

Laterally Loaded Pile ◽

Laterally Loaded ◽

Limiting Pressure

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Non-Darcy effects in fracture flows of a yield stress fluid

Journal of Fluid Mechanics ◽

10.1017/jfm.2016.491 ◽

2016 ◽

Vol 805 ◽

pp. 222-261 ◽

Cited By ~ 24

Author(s):

A. Roustaei ◽

T. Chevalier ◽

L. Talon ◽

I. A. Frigaard

Keyword(s):

Pressure Gradient ◽

Yield Stress ◽

Single Phase ◽

Stokes Problem ◽

Type Flow ◽

New Type ◽

Approximate Expressions ◽

Limiting Pressure Gradient ◽

Selection Of ◽

Limiting Pressure

We study non-inertial flows of single-phase yield stress fluids along uneven/rough-walled channels, e.g. approximating a fracture, with two main objectives. First, we re-examine the usual approaches to providing a (nonlinear) Darcy-type flow law and show that significant errors arise due to self-selection of the flowing region/fouling of the walls. This is a new type of non-Darcy effect not previously explored in depth. Second, we study the details of flow as the limiting pressure gradient is approached, deriving approximate expressions for the limiting pressure gradient valid over a range of different geometries. Our approach is computational, solving the two-dimensional Stokes problem along the fracture, then upscaling. The computations also reveal interesting features of the flow for more complex fracture geometries, providing hints about how to extend Darcy-type approaches effectively.

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Limitations of Conjugate Gear Tooth Surfaces in Order to Avoid Undercutting and Appearance of Envelope of Lines of Contact

14th Design Automation Conference ◽

10.1115/detc1988-0053 ◽

1988 ◽

Author(s):

F. L. Litvin ◽

D. J. Kin ◽

Y. Zhang

Keyword(s):

Computer Graphics ◽

Gear Tooth ◽

Worm Gear ◽

Singular Points ◽

Line Contact ◽

Gear Drive ◽

Pressure Angle ◽

Tooth Surfaces ◽

Limiting Pressure

Abstract Gear tooth surfaces being in line contact at every instant are considered. The dimensions of the contacting surfaces must be limited in order to avoid: (i) the appearance of the envelope of lines of contact on the generating surface Σ1 and (ii) the appearance of singular points on the generated surface Σ2. The relations between the developed concepts and the Wildhaber’s concept of the limiting pressure angle are investigated. Applications to the worm-gear drive and the generation of a pinion of a formate gear drive are considered. Computer graphics have been used to illustrate the results of computation.

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THE TRIBOLOGICAL PROPERTIES OF LUBRICATING GREASES BASED ON RENEWABLE OILS

Tribologia ◽

10.5604/01.3001.0010.7565 ◽

2016 ◽

Vol 266 (2) ◽

pp. 61-72

Author(s):

Rafał KOZDRACH

Keyword(s):

Disperse Phase ◽

Vegetable Oils ◽

Tribological Properties ◽

Castor Oil ◽

Rapeseed Oil ◽

Modified Silica ◽

Limiting Load ◽

Antiwear Properties ◽

Lubricating Properties ◽

Limiting Pressure

The paper discusses the influence of vegetable oil basis on lubricating properties of their selected compositions. Four vegetable oils were used for production of lubricating greases: rapeseed, sunflower, soybean, and castor, all thickened with modified silica of Aerosil® type. The tribological properties of lubricating greases based on vegetable oils were investigated. On their basis, the most beneficial compositions were selected. The tribological properties of greases were estimated via measurements of limiting load of wear (Goz/40), welding load (Pz), scuffing load (Pt), limiting load of scuffing (Poz), and the limiting pressure of seizure (Poz). Based on the obtained results, it may be concluded that the best antiwear properties were shown by the lubricating compositions based on rapeseed oil, whereas the best antiscuffing properties have compositions using castor oil as a disperse phase.

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Discussion: The limiting pressure on a circular pile loaded laterally in cohesive soil

Géotechnique ◽

10.1680/geot.1986.36.3.457 ◽

1986 ◽

Vol 36 (3) ◽

pp. 457-457 ◽

Cited By ~ 1

Author(s):

M. F. Randolph ◽

G. T. Houlsby

Keyword(s):

Cohesive Soil ◽

Limiting Pressure

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Interdependence of regional expiratory flow

Journal of Applied Physiology ◽

10.1152/jappl.1985.59.6.1924 ◽

1985 ◽

Vol 59 (6) ◽

pp. 1924-1928 ◽

Cited By ~ 18

Author(s):

T. A. Wilson ◽

J. J. Fredberg ◽

J. R. Rodarte ◽

R. E. Hyatt

Keyword(s):

Lung Volume ◽

Regional Differences ◽

Vital Capacity ◽

Maximum Flow ◽

Bronchial Tree ◽

Lung Compliance ◽

Junction Flow ◽

Expiratory Flow ◽

The Difference ◽

Limiting Pressure

Flows from different lung regions interact at the junctions of the bronchial tree, and flow from each region depends on the driving pressures for other regions. At each junction, flow from the region with the higher driving pressure is favored. As a result there is a limit on the difference in alveolar pressures that can develop during expiratory flow from a lung with regional differences in lung compliance and airway resistance. The limiting pressure difference is smaller for lower flow. A nonuniform lung therefore empties more uniformly if it empties slowly, and maximum flow at low lung volume may be greater than it would be at the same lung volume during a maximal expiratory vital capacity maneuver.

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