| ATTRIBUTE | VALUE |
|---|---|
| type | C |
| database id | 7992 |
| title | |
| authors | |
| affiliations | |
| year | 2012 |
| series | Archives of Hydro-Engineering and Environmental Mechanics |
| issue | Vol. 59, No. 1-2 |
| publisher | Wydawnictwo IBW PAN |
| place | Gdańsk |
| attributes | [published] [reviewed] [scientific] [international reach] |
| language | en |
| ATTRIBUTE | VALUE |
|---|---|
| type | A |
| database id | 7668 |
| title | Deformations and liquefaction of granular soils in plane strain conditions |
| authors | Sawicki A., Sławińska J. |
| pages | 13 — 35 |
| notes | Kopia w oprac. Tp4314 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem59str013.pdf |
| keywords | granular soils, deformations, liquefaction, stability, plane strain conditions |
| affiliations | |
| tasks | T 3.1/2011: Podstawy mechaniki gruntów sypkich |
| abstracts | An incremental model is proposed to describe pre-failure behaviour of granular soils in plane strain conditions. The model has been derived from an approach applied in the analysis of triaxial tests. We have applied the methods of tensor algebra to transfer our triaxial results to a 2D case. The model describes the pre-failure deformations of fully drained sands and phenomena associated with undrained response such as static liquefaction. This model has a simple structure in the form of incremental equations. For some simple loading paths, these equations can be integrated analytically. For more complex loading paths a simple numerical algorithms will be sufficient. The model takes into account an initial anisotropy of soil which is ignored in most models. It also takes into account the initial state of soil, defined as rather contractive or dilative, in addition to classical geotechnical division into loose and dense sands. The proposed constitutive equations allow the study of pre-failure instabilities of sand, and some examples are presented. We have also derived analytically the equation for an instability line. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|---|
| type | A |
| database id | 8068 |
| title | Transversal pressure effect in circulative separators |
| authors | Jerzy M. Sawicki |
| pages | 3 — 12 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem59str003.pdf |
| keywords | centrifugal force, cyclones, rotational separators, sedimentation, waste water treatment |
| affiliations | |
| abstracts | Progressive urban development of the human environment requires new methods of rain water treatment. Recently, there has been a growing interest in the improvement of gravitational suspension separation, and especially in the application of the centrifugal force. This important factor can be induced in two ways; by the circulation of the reservoir containing the fluid (centrifugal separators), or by a tangent supply of this reservoir (circulative separators). In addition to the centrifugal force, another essential transversal force is at work in this case, resulting from the local variability of the pressure. In the literature, this force is derived for centrifuge conditions, but applied also to circulative separators, which is questionable, as in the latter devices velocity and pressure fields are clearly different. The paper is devoted to the determination of the transversal pressure effect in circulative separators. First, a model of tangent and radial velocity profiles is introduced. The radial pressure distribution, calculated on this basis and verified experimentally, leads to the final result, that is, a technical formula describing the force in question. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|---|
| type | A |
| database id | 8069 |
| title | Wind influence on the formation of nearshore currents in the southern Baltic: mumerical modelling results |
| authors | Andrei Sokolov, Boris Chubarenko |
| pages | 37 — 48 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem59str037.pdf |
| keywords | currents, waves, numerical modeling, coastal zone, the Baltic Sea |
| affiliations | |
| abstracts | A two-dimensional numerical model was used for a simulation of vertical average longshore currents generated by both wind friction and wind-wave action in the nearshore zone. The modelling domain includes the southern part of the Baltic Proper (all boundaries were closed). Wind, uniform in space and varying in time, was the only forcing in the model. The correlation coefficient higher than 0.8 was obtained by model calibration versus the field measurements of currents conducted at the Lubiatowo field station (southern Baltic) during about 1.5 months in 2006. Comparative simulations of total currents including both wind-induced drift and wave components, and of total currents including only a wind-induced drift component, showed that the input of the drift component into currents in the nearshore zone is greater than commonly believed. Wind-induced drift strongly dominates outside the zone of wave transformation, and its input into the total resulting currents remains noticeable even in a zone between the shoreline and the depth of the first wave breaking. Thus, wind-induced drift constitutes up to 50% of the resulting longshore currents for longshore winds and no less than 20% of the longshore component of currents for winds at 45 degrees to the longshore direction. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|---|
| type | A |
| database id | 8070 |
| title | Specification of forces in rotational separator |
| authors | Marlena A. Gronowska |
| pages | 49 — 62 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem59str049.pdf |
| keywords | centrifugal force, rotational separator, sedimentation, storm water, waste water treatment |
| affiliations | |
| abstracts | Today, intensive urban development calls for new technologies in the field of environmental engineering. Extensive infrastructure requires more roads and motorways, as well as larger areas covered with concrete, which altogether leads to greater volumes of water creating surface run-off. Rotational separators, besides lamella and coalescence units, may provide a highly efficient method for treatment of storm water running off roads and motorways. This paper is focused on two important aspects of the operation of rotational separators: forces acting on a particle in liquid flow, and pressure distribution in the chamber. The resulting relations constitute crucial elements in the future method of designing such devices. |
| attributes | [reviewed] [scientific] |
| language | en |
| ATTRIBUTE | VALUE |
|---|---|
| type | A |
| database id | 8071 |
| title | Geotechnical parameters of alluvial soils from in-situ tests |
| authors | Zbigniew Młynarek, Katarzyna Stefaniak, Jędrzej Wierzbicki |
| pages | 63 — 81 |
| full text link | http://www.ibwpan.gda.pl/storage/app/media/ahem/ahem59str063.pdf |
| affiliations | |
| abstracts | The article concentrates on the identification of geotechnical parameters of alluvial soil represented by silts found near Poznań and Elbląg. Strength and deformation parameters of the subsoil tested were identified by the CPTU (static penetration) and SDMT (dilatometric) methods, as well as by the vane test (VT). Geotechnical parameters of the subsoil were analysed with a view to using the soil as an earth construction material and as a foundation for buildings constructed on the grounds tested. The article includes an analysis of the overconsolidation process of the soil tested and a formula for the identification of the overconsolidation ratio OCR. Equation 9 reflects the relation between the undrained shear strength and plasticity of the silts analyzed and the OCR value. The analysis resulted in the determination of the Nkt coefficient, which might be used to identify the undrained shear strength of both sediments tested. On the basis of a detailed analysis of changes in terms of the constrained oedometric modulus M0, the relations between the said modulus, the liquidity index and the OCR value were identified. Mayne’s formula (1995) was used to determine the M0 modulus from the CPTU test. The usefullness of the sediments found near Poznań as an earth construction material was analysed after their structure had been destroyed and compacted with a Proctor apparatus. In cases of samples characterised by different water content and soil particle density, the analysis of changes in terms of cohesion and the internal friction angle proved that these parameters are influenced by the soil phase composition (Fig. 18 and 19). On the basis of the tests, it was concluded that the most desirable shear strength parameters are achieved when the silt is compacted below the optimum water content. |
| attributes | [reviewed] [scientific] |
| language | en |