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Static load test curve (Q–s) conversion in to pile of different size

100%

Meyer Z., Stachecki K.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2018

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tom 50

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nr 2

2

Effect of labour organisation on the level of energy expenditure and static loads of a worker in intermediate cutting

84%

Stempski W.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2009

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tom 08

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nr 2

The aim of the performed experiments was to assess energy expenditure and static loads of the operator of a chain sawing machine harvesting timber in a pine stand intermediate cutting. The investigations included two technological variants. In variant I, all technological operations were carried out by one worker – operator of the chain saw, while in treatment II the operations were carried out by a team of three persons – two operators of chain sawing machines and a helper. The energy expenditure was determined on the basis of measurements of the ventilation of lungs, whereas the static load – using the OWAS method. The determined net unit energy expenditures of the chain saw operators in the experimental variants exceeded 20 kJ•min-1 and differed statistically significantly between one another. With regard to static loads, a greater proportion of positions negatively affecting the muscle-skeletal system of the operator were found in variant II.

3

Usability analysis of static load cycles for assessment of tractor engine operation economy

84%

Koniuszy A.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2008

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tom 08

4

Large-size mechanically joined timber structure subjected to short-term and long-term load

84%

Sulik P., Piekarczuk A., Sudol E.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2013

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tom 84

5

Soil stress state determination under static load

84%

Pytka J., Horn R., Kuhner S., Semmel H., Blazejczak D.

International Agrophysics

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1995

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tom 09

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nr 3

6

Investigations on the properties of solvent and dispersion adhesives for upholstered furniture. Part III. Thermoresistance of glue lines in PUR foams-wood or particleboard systems

67%

Krystofiak T., Lis B., Proszyk S., Wachowiak M.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2013

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tom 83

7

Selected construction and material aspects of moulded plywood production for use in sports equipment

67%

Borysiuk P., Tereszczak P., Jenczyk-Tolloczko I., Boruszewski P., Wilkowski J.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2015

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tom 90

8

Wplyw wybranych czynnikow na wlasciwosci mechaniczne tkanki korzenia buraka cukrowego

67%

Gorzelany J., Sosnowski S.

Acta Agrophysica

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2003

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tom 02

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nr 1[95]

73-82

9

Dynamic and cyclic static loading behavior of silty-sandy clay at small and moderate strains

67%

Gabrys K., Sas W., Sobol E.

Acta Scientiarum Polonorum. Architectura

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2016

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tom 15

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nr 4

The shear modulus (G) is one of the key parameters for seismic ground response analysis and it can be usually determined by means of dynamic tests (DT), such as resonant column test (RCT), or cyclic static test (CST), e.g. torsional shear (TST). The RC and TS tests are widely used laboratory methods to find stiffness of soil at small to medium strain range (0.0001–0.5%). The purpose of this paper is to present the experimental results from RC and CS laboratory tests on silty-sandy clay from the western part of Warsaw, Poland. The study aims to compare the shear modulus values obtained from two different research techniques. The influence of, in particular, the applied effective pressure, associated shear strain and experimental method (i.e. loading frequency and output amplitude) on the shear modulus at small strains (Gmax) and secant shear modulus (G) are investigated and proved. Generally, the results reveal that the examined soils stiffness calculated from TS tests is lower than from RC tests.

10

Badania odbiorcze w zakresie obciążeń statycznych betonowego mostu drogowego o konstrukcji sprężonej położonego nad budowlą zrzutową zbiornika wodnego

67%

Mordak A., Manko Z.

Acta Scientiarum Polonorum. Architectura

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2004

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tom 03

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nr 1

11

Wplyw wlasciwosci mechanicznych ziarna pszenicy na rozklad obciazenia w zbiorniku

51%

Horabik J.

Acta Agrophysica

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1994

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tom 01

71

To describe mechanical behaviour of a granular material it is indispensable to have parameters such as the coefficient of friction on a bin wall, the angle of internal friction and the bulk density and the k-value in Janssen's equation. The values of these parameters depend on many known and unknown factors. In the case of plant granular solids indisputable is the role of moisture content of grain, vertical pressure and sliding velocity. The purpose of this study was to determine the influence of mechanical properties of wheat grain on wall and bottom load distribution in a model grain bin. A series of tests involving eight filling methods, eccentric discharge from five different locations of a bin orifice and three bin wall surfaces were conducted on a laboratory scale cylindrical bin 0.61 m in diameter and 2.44 m high. The wall and flat floor of the bin were supported independently on three load cells so that load distributions could be isolated. Static and dynamic wall and bottom loads were found to be influenced by the filling method. Shower filling produced lower static load of the smooth wall as compared to central filling and higher static load of corrugated and rough walls. The experiments showed a significant influence of grain orientation on load distribution. Variable angle of internal friction within the Janssen differential element can explain the non-uniform load distribution obtained. The horizontal bending moments exerted on the wall and floor of the bin during eccentric discharge were found to decrease with an increase in the bin wall friction coefficient and were influenced significantly by the orifice eccentricity ratio, with the maximum moment occurring at ER equal to 0.667. The horizontal pressure distribution around the circumference of the bin wall depends on the height from the floor. Near the floor of the bin the horizontal pressure was larger on the side of the bin opposite the discharge orifice, while for locations higher above the floor, the horizontal pressure was larger on the side nearest the discharge orifice. As the ratio of the grain height to the bin diameter decreased below approximately 1 a change in the direction of the resultant friction force on the bin wall from a normal downward direction to an upward direction was observed. The change in direction of the resultant tangent force originates from the combination of the downward friction force of flowing grain and the upward friction force of the grain contained within the dead zone of the bin. Moisture content of grain influences its compressibility, friction against the bin wall, height of the dead zone and, in consequence, the upward movement of grains in the dead zone of the flat bottom bin during discharge.

Ograniczanie wyników

Static load test curve (Q–s) conversion in to pile of different size

Effect of labour organisation on the level of energy expenditure and static loads of a worker in intermediate cutting

Usability analysis of static load cycles for assessment of tractor engine operation economy

Large-size mechanically joined timber structure subjected to short-term and long-term load

Soil stress state determination under static load

Investigations on the properties of solvent and dispersion adhesives for upholstered furniture. Part III. Thermoresistance of glue lines in PUR foams-wood or particleboard systems

Selected construction and material aspects of moulded plywood production for use in sports equipment

Wplyw wybranych czynnikow na wlasciwosci mechaniczne tkanki korzenia buraka cukrowego

Dynamic and cyclic static loading behavior of silty-sandy clay at small and moderate strains

Badania odbiorcze w zakresie obciążeń statycznych betonowego mostu drogowego o konstrukcji sprężonej położonego nad budowlą zrzutową zbiornika wodnego

Wplyw wlasciwosci mechanicznych ziarna pszenicy na rozklad obciazenia w zbiorniku