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Abstract

The subject of this article is the analysis of the relationship between G 0/ M DMT and K D, where G 0 is the small strain shear modulus, while M DMT and K D are respectively the constrained modulus and the horizontal stress index determined from DMT tests. This relationship allows to determine a profile with depth of G 0 from standard DMT test results, useful when data from nonseismic DMT investigations are available. The analysis was based on a large amount of data for a wide range of soils of different origins in Poland. The dataset included OC and NC loams, silts, medium sands, silty sands and fine sands. The overconsolidation ratio (OCR) was estimated using data from CPTU and DMT tests. The obtained empirical G 0/ M DMT vs. K D relationships were compared with the correlations established by Marchetti et al. [1] for different soil types. To account for the significant influence of overconsolidation, an original empirical relationship between G 0/�� p and K D, where �� p is the preconsolidation stress, was defined based on data from all investigated fine-grained soils.
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Authors and Affiliations

Zbigniew Młynarek
1
ORCID: ORCID
Jędrzej Wierzbicki
2
ORCID: ORCID
Paola Monaco
3
ORCID: ORCID
Katarzyna Stefaniak
2
ORCID: ORCID

  1. University of Life Sciences, Poznan, Poland
  2. Institute of Geology, Adam Mickiewicz University, Poznan, Poland
  3. University of L’Aquila, L’Aquila, Italy
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Abstract

Conventional membranes used in the process of premix membrane emulsification are prone to fouling, especially when biopolymers are employed as surfactants. An alternative to conventional membranes are dynamic membranes consisting of an unconsolidated porous medium. Dynamic membranes have the advantage of enabling easy cleaning of the inside of the pores. Experimental research carried out to date has focused on the application of hydrophilic dynamic membranes composed of glass microbeads for producing o/w emulsions. The aims of this study were to determine the efficiency of droplet size reduction in a w/o emulsion when passed through a dynamic hydrophobic membrane consisting of a bed of irregular polymer particles, and to assess the effect of multiple membrane passes on the properties of the w/o emulsion. The dynamic membranes evaluated in the tests were found to reduce the diameters of premix droplets when an appropriate pressure level was reached. Higher bed porosity was associated with greater fluxes achieved across the packed bed, but the resulting emulsions were less homogeneous. Multiple passes of the emulsion through the dynamic polypropylene membrane led to a further reduction in droplet size, but it was accompanied by a decline in emulsion homogeneity.
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Authors and Affiliations

Adrianna Frankiewicz
1
ORCID: ORCID
Jacek Różański
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Chemical Technology and Engineering, ul. Berdychowo 4, 60-965 Poznan, Poland
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Abstract

The presence of soft soil of river and organic genesis in the basement of road embankments creates problems related to their high deformability. Difficult to assess water permeability, affecting the course of the consolidation and settlement process, requires field studies, such as dilatometer tests. In engineering practice, there are many factors that can affect the basement consolidation process, but they are not simply applied to theoretical models. In many cases, only the observational method allows the selected computational approach to be applied to a specific engineering problem. For this reason, it is one of the approaches strongly emphasized by Eurocode 7. The article presents an example of the application of a temporary load from heavy construction traffic to the consolidation of soft soil under service roads with verification of the subsoil parameters using the dilatometer tests. A horizontal layer of weak soil, loaded with a vertical external load caused by temporary traffic, was assumed for the calculations. For such an arrangement, the classical solution of uniaxial Terzaghi’s consolidation with the water flow in the vertical direction was applied. A computational analysis of the consolidation time and maximum settlement values was performed.
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Authors and Affiliations

Grzegorz Bartnik
1
ORCID: ORCID
Rafał Kuszyk
1
ORCID: ORCID
Małgorzata Superczyńska
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland

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