Research Article
Geotechnical Study and Mechanical Characterization of Two Djarmaya Soils in Chad
Mahamat Adoum Abdraman*,
Idriss Mahamat Yaya,
Mahamat Nour Abdallah,
Mahamat Hassane Daoud,
Mahamat Kher Nediguina,
Abakar Mahamat Tahir,
Ruben Mouangue
Issue:
Volume 13, Issue 1, February 2024
Pages:
1-5
Received:
26 November 2023
Accepted:
2 January 2024
Published:
18 January 2024
Abstract: This work concerns the geotechnical and mechanical studies of the soils of two sites located in the locality of Djarmaya located 5 km from the oil refinery. First, these two sites were located and then a site raid was carried out. The experimental devices used as well as certain physical and mechanical parameters were studied. Finally, the geotechnical characterizations of two soils focused on the particle size analysis by sieving and sedimentometry, the Atterberg boundaries, and the density of the solid grains. We observe that there is a similarity between the results obtained. However, the first sample consists of two samples have almost the same amount of silt, but there is a slight difference in terms of sand and clay. However, the results showed us that the soils are clayey and not very plastic. This result shows that flexural and compressive strengths vary with increasing cow dung. When the percentage of cow dung increases from 0 to 4%, the flexural strength also decreases from 0.79MPa to 1.15MPa. Similarly, compressive strength increases from 1.98 MPa to 2.25 MPa when the percentage of cow dung increases from 0% to 4%. This variation in flexural strength is explained by the behaviour of cow dung due to the fact that it is a lightweight material and by the mode of failure. During drying, the specimens did not shrink. In addition to the geotechnical test, a mechanical characterization study of the latter showed that the soils were suitable for construction.
Abstract: This work concerns the geotechnical and mechanical studies of the soils of two sites located in the locality of Djarmaya located 5 km from the oil refinery. First, these two sites were located and then a site raid was carried out. The experimental devices used as well as certain physical and mechanical parameters were studied. Finally, the geotechn...
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Research Article
Dielectric Relaxation, Electric Conductivity and Thermodynamic Studies on Epoxy Polyurethane Blend and Their Composites
Issue:
Volume 13, Issue 1, February 2024
Pages:
6-12
Received:
30 December 2023
Accepted:
18 January 2024
Published:
1 February 2024
Abstract: The purpose of this study is to improve the dielectric properties of epoxy-based polymer composites by adding rock and glass wool to achieve a relatively high dielectric constant and lower dispersion; hence the dielectric relaxation of composite materials which combines of epoxy/polyurethane reinforced with fibrous materials (rock wool (RW) and glass wool (GW)) with constant weight fraction of (10%) were investigated. The data of AC conductivity have been analyzed in the light of different theoretical models based on correlated barrier hopping (CBH) and Maxwell-Wagner model. The dielectric measurements were carried out for all samples over the frequency range of (102-107) Hz and over temperature range of (293-463) K0. It is found that all samples displayed dielectric dispersion, thus the result for dielectric constant and dissipation factor give a direct evidence of the existence of Debye relaxation leaving a wide distribution of relaxation time. Eyring’s relaxation rate equation have been used to determine the thermodynamic parameters, Gibbs free energy of activations and enthalpy for all samples. The results showed the existence of a stronger intermolecular interaction in all samples.
Abstract: The purpose of this study is to improve the dielectric properties of epoxy-based polymer composites by adding rock and glass wool to achieve a relatively high dielectric constant and lower dispersion; hence the dielectric relaxation of composite materials which combines of epoxy/polyurethane reinforced with fibrous materials (rock wool (RW) and gla...
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