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Abstrakt

Przy wstępnym oczyszczaniu ścieków z zakładów rafineryjno-petrochemicznych powstają płynne osady ściekowe o wysokim uwodnieniu i tylko nieco mniejszym procencie węglowodorów. Osady te są gromadzone w bezodpływowych zbiornikach, gdyż nie ma dla nich zastosowania. Niniejsze badania miały na celu w pierwszym etapie zamianę osadów o charakterze płynnym na osad o konsystencji stałej (produkt) przez dodanie wapna palonego, a następnie utylizację tak wytworzonego produktu w budownictwie drogowym jako kilkuprocentowego dodatku do dolnych warstw drogi. Drugi etap badań dotyczył oceny wpływu produktu wbudowanego w podłoże dróg lub placów na środowisko wód podziemnych i powierzchniowych przez analizę zmian składu chemicznego tych wód w bezpośrednim sąsiedztwie zrealizowanych doświadczalnych odcinków dróg. Przy zachowaniu odpowiednich proporcji pomiędzy produktem i naturalnym materiałem drogowym wpływ ten mieści się w granicach dopuszczalnych prawem.
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Autorzy i Afiliacje

Bronisław Bartkiewicz
Iwona Obierak

Abstrakt

The analysis of the costs and emissions of greenhouse gases for individual phases of construction investments allows for the implementation of solutions and the prevention of negative environmental impacts without significantly increasing construction costs. The share of individual investment phases in the amount of carbon dioxide (CO2) produced for the construction and use of buildings depends mainly on the materials used and the implemented design solutions. In accordance with the idea of sustainable construction, materials and design solutions with the lowest possible carbon footprint should be used. This can be achieved by using natural building materials, materials subjected to appropriate chemical composition modifications, or materials in which their production does not require large amounts of energy. The aim of the article is to determine the value of the purchase costs of selected road materials (concrete paving blocks, cement-sand bedding, concrete curbs, semi-dry concrete and concrete underlay, washed sand, and crushed aggregate with a fraction of 0–31.5 mm) for the implementation of a road investment. In addition, the authors focused on determining the size of the embodied carbon footprint due to GHG (greenhouse gas) emissions and GHG removals in a product system, expressed as CO2 equivalents for the same materials that were subjected to cost analyzes. The article presents the results of original analyzes, and indicates the optimal solutions in terms of minimizing the cost of purchasing road materials and minimizing the carbon footprint. The discussion also covers the issue of changing the chemical composition in the context of the potential impact on the reduction of material costs and CO2 equivalent emissions.
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Autorzy i Afiliacje

Damian Wieczorek
1
ORCID: ORCID
Krzysztof Zima
1
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Civil Engineering, Warszawska 24, 31-155 Kraków, Poland

Abstrakt

Malaysia’s construction industry is experiencing rapid growth, translating into increased demand for cement. However, cement production pollutes the air to the detriment of the climate via CO2 emission, making research into a cementitious replacement in concrete a necessity. This paper details an experimental study of self-compacting concrete (SCC) with partial replacement of cement by rice straw ash (RSA), which is expected to result in environmental preservation due to the green materials being used in cement production. The physicomechanical properties of the SCC with RSA replacement were determined via its compressive strength, water absorption, self-workability, and fire resistance (residual strength after exposure to high temperatures). The proportion of RSA replacement used were 0%, 5%, 10%, 15%, 20%, and 25%, and all passed the slump flow test, except the 20% and 25% samples. The SCC samples with 15% of RSA replacement reported the highest compressive strength at 7 and 28 curing days and the highest residual strength post-exposure to high temperatures. The lowest percentage of water absorption was reported by the 15% of RSA replacement, with a density of 2370 kg/m3.
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Autorzy i Afiliacje

Rafiza Abd Razak
1 2
ORCID: ORCID
Yi Qin Chin
1
ORCID: ORCID
Mohd Mustafa Al Bakri Abdullah
3 2
ORCID: ORCID
Zarina Yahya
1
ORCID: ORCID
Mokhzani Khair Ishak
1
ORCID: ORCID
Sebastian Garus
4
ORCID: ORCID
Marcin Nabiałek
5
ORCID: ORCID
Warid Wazien Ahmad Zailani
6
ORCID: ORCID
Khairil Azman Masri
7
ORCID: ORCID
Andrei Victor Sandu
8
ORCID: ORCID
Agata Śliwa
9
ORCID: ORCID

  1. Universiti Malaysia Perlis, Faculty of Civil Engineering Technology, 02100 Padang Besar, Perlis, Malaysia
  2. Centre of Excellence Geopolymer and Green Technology (CEGeoGTech)
  3. Universiti Malaysia Perlis, Faculty of Chemical Engineering, 01000, Kangar, Perlis, Malaysia
  4. Faculty of Mechanical Engineering and Computer Science, Czestochowa University of Technology, Czestochowa, Poland
  5. Department of Physics, Czestochowa University of Technology, Czestochowa, Poland
  6. UniversitiTeknologi MARA, School of Civil Engineering, College of Engineering, 40450 ShahAlam, Selangor, Malaysia
  7. 1 Department of Civil Engineering, College of Engineering, Universiti Malaysia Pahang, 26300 Gambang Kuantan Pahang, Malaysia
  8. Faculty of Materials Science and Engineering, Gheorghe Asachi Technical University of Iasi, 71 D. Man-geron Blv., 700050 Iasi, Romania
  9. Division of Materials Processing Technology and Computer Techniques in Materials Science, Silesian University of Technology, 44-100 Gliwice, Poland

Abstrakt

This research aims to determine the influence of the cyclic process of freezing and defrosting on the mechanical properties of the chosen glass fibres and PTFE-coated woven fabrics. The specimens were subjected to freezing at about -20˚C for 4 h and thawing by full immersion into the water at about +20˚C for 4 h. The fabric samples after 25 and 50 frozen cycles were air-dried at room temperature for one week and then subjected to uniaxial tensile tests. The same tests have been performed on a reference group of specimens, which were not exposed to temperature change. The authors determined the tensile strength, and longitudinal stiffnesses resulting from performed tests. Although the investigated coated woven fabrics expressed a reduction in the tensile strength in water soaking conditions, the performed frozen cycles don’t show a significant decrease in strength under uniaxial tensile tests.
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Autorzy i Afiliacje

Andrzej Ambroziak
1
ORCID: ORCID
Paweł Kłosowski
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, St. Gabriela Narutowicza 11/12, 80-233 Gdansk, Poland

Abstrakt

This research aims to determine the influence of water-soaking on polyester-based coated woven fabrics for ultimate tensile strength and elongation at break under uniaxial tensile tests. The paper begins with a short survey of literature concerning the investigation of the determination of coated woven fabric properties. The authors carried out the uniaxial tensile tests with an application of a flat grip to establish the values of the ultimate tensile strength of groups of specimens treated with different moisture conditions. SEM fractography is performed to determine the cross-section structures of coated woven fabrics. The change in the mechanical properties caused by the influence of water immersion has not been noticed in the performed investigations.
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Autorzy i Afiliacje

Andrzej Ambroziak
1
ORCID: ORCID
Paweł Kłosowski
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Civil and Environmental Engineering, St. Gabriela Narutowicza 11/12, 80-233 Gdansk, Poland

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