The main objectives of this study were to apply the ultrasonic non-destructive testing to a histo... more The main objectives of this study were to apply the ultrasonic non-destructive testing to a historical rammed earth material in order to identify altered zones and to elaborate a methodology for the health diagnosis and the control of restoration. The ultrasonic surface measurements using a Pundit 54 KHz on chosen panels has led to construct P-wave velocities tomograms. The use of other waveform attributes such as the signal amplitude allowed studying the attenuation and loss of energy related to weathering. The application of the conventional Schmidt hammer test allowed to establish maps of the rebound values R and to assess the mechanical hardness of the raw and the restored panels. These methodologies are well known and applied to concrete, but still not adapted to earth material (pise). The mean idea is to combine both techniques to estimate a compressive strength through nondestructive tests, and at the end contributing to elaborate a kind of standardized charts. These prelimin...
Volublis’deki Roma mozaikleri opus tessellatum tipindedir. Bu mozaikler, Lacunae duzeninde (tesse... more Volublis’deki Roma mozaikleri opus tessellatum tipindedir. Bu mozaikler, Lacunae duzeninde (tesserae eksikligi) belirtilenden farkli bir bozulma ozelligi gostermekte olup mozaik dosemeleri catlaklarla ve kirilmalarla bozu- lur. Tessellatum’un bozulmasi ve catlaklarin duzeni mozaigi tasiyan topraktaki kabarmalarla iliskilidir. Ayrica, doseme tesserae aralarinda ve altinda bulunan ve onlara onemli derecede gozeneklilik veren ve tessellatumun kolayca cokmesine sebep olan ince taneli harctaki (ince taneli kirec ve kuvars) kimyasal bozulmalar nedeniyle de zarar gorebilir. Kimyasal cozunmeden dolayi kabarcik olusumu gosteren kirectasi tesseranin disinda, mer- mer ve cam tesseralar kotu havadan asinmalara karsi direnc gostermektedir
International journal of engineering research and technology, 2013
In Zeida abandoned mine, huge amount of mining dams were left without any adjustment and remediat... more In Zeida abandoned mine, huge amount of mining dams were left without any adjustment and remediation. Their exposition leads to mass erosion and transport over large distance in the watershed. Chemical analysis of these wastes show high contamination by heavy metals especially in fine grain size fraction. The leachate of wastes leads to the contamination of pit lake waters, the low content of Pb and Zn in the most sampled lakes is related to their low mobility in alkaline solution and their adsorption by clay and iron hydroxides. While high values recorded in As are attributed to its methylation by organic matter. Stream sediments show high contamination due to their location downstream the mining districts.
Journal of Environmental and Engineering Geophysics, 2020
The tailings of Zeida's abandoned mine are found near the city of Midelt, in the middle of th... more The tailings of Zeida's abandoned mine are found near the city of Midelt, in the middle of the high Moulouya watershed between the Middle and the High Atlas of Morocco. The tailings occupy an area of about 100 ha and are stored either in large mining pit lakes with clay-marl substratum or directly on a heavily fractured granite bedrock. The high contents of lead and arsenic in these tailings have transformed them into sources of pollution that disperse by wind, runoff, and seepage to the aquifer through faults and fractures. In this work, the main goal is to identify the pathways of contaminated water with heavy metals and arsenic to the local aquifers, water ponds, and Moulouya River. For this reason, geophysical surveys including electrical resistivity tomography (ERT), seismic refraction tomography (SRT) and very low-frequency electromagnetic (VLF-EM) methods were carried out over the tailings, and directly on the substratum outside the tailings. The result obtained from comb...
In the Zeida abandoned mine, pit lake waters exhibit alkaline pH and high conductivity. The conce... more In the Zeida abandoned mine, pit lake waters exhibit alkaline pH and high conductivity. The concentrations of the total dissolved lead and zinc are very low due to their adsorption on clay minerals and iron oxyhydroxides. Conversely, arsenic concentrations in two lakes (ZL1 and ZA) exceed WHO water quality guidelines. The As content is relatively high in ZL1 and exists mainly as As(V). In ZA, As(III) occurs in low concentration compared to the total dissolved arsenic, while dimethylarsenic acid (H2AsO2(CH3)2, DMA) prevails. This means that arsenic was methylated by organic matter produced by micro-organisms such as chlorella. The sequential extraction of floor sediments in the two lakes shows that the bioavailable arsenic contents change between them. In ZA, the sediments show high concentrations of lead and arsenic compared to the ZL1 sediment since it is surrounded by mining waste tailings, which are rich in these elements. An arsenic leaching test of ZA sediment shows that bioava...
Journal of Environmental and Engineering Geophysics, 2017
The abandoned lead mine of Zeida is located at the center of the High Moulouya watershed between ... more The abandoned lead mine of Zeida is located at the center of the High Moulouya watershed between the Middle and the High Atlas Mountains of Morocco. Zeida has produced a total of 640,000 tons of concentrated lead during the 14 years of its activity (1972–1985). Three large tailings were left at the center of the mine on both sides of Moulouya River without any risk reduction measures or monitoring and there is a concern regarding heavy metal contamination of local groundwater. Samples taken from and around the tailings were found to contain average lead and zinc concentrations of 3,000 ppm and 140 ppm, respectively, primarily in the form of galena and barite. Prior studies have also found high concentrations of lead and zinc in both local wells near the town of Zeida and along the banks of Moulouya River. In this study, five electrical resistivity imaging surveys were performed to identify the risk of pollution and trace the pathways of mine-based contaminants to groundwater and to ...
The objective of this study is to conduct a mineralogical and chemical characterization of the mo... more The objective of this study is to conduct a mineralogical and chemical characterization of the mortars Roman archaeological site of Volubilis to rebuild spare mortars for restoration. We take samples of mortar, broken tile palate garden, and pavement mosaic Falavius Germanus houses. The analysis by X-ray diffraction reveals the coarse mortar Flavius Germanus is made of quartz and calcite with feldspar and probably, mica and dolomite in small amounts. The binder end is formed calcite and quartz. However, the broken tile mortar is formed by coarse particles, clay base mixed with a binder phase dominated by calcite. These results allowed us to reformulate spare mortars for the restoration of damaged Roman mosaics. The mortars are made up by 63.6% of lime and 36.4% of sand(with 4.19% of large grain, 71, 04% of coarse sand, 24.22%, of fine sand and 0.55% fines parts).The performance of these mortars was tested by mechanical testing.
In the abandoned mine in Zaida, the pit lakes filled with water constitute significant water rese... more In the abandoned mine in Zaida, the pit lakes filled with water constitute significant water reserves. In these lakes, the waters are permanently in contact with ore deposit (cerussite and galena). The modelling of the interaction of waters with this mineralization shows that cerussite dissolves more rapidly than galena. This dissolution is controlled by the pH and dissolved oxygen concentration in solution. The lead concentrations recorded in these lakes come largely from the dissolution of cerussite.
The main objectives of this study were to apply the ultrasonic non-destructive testing to a histo... more The main objectives of this study were to apply the ultrasonic non-destructive testing to a historical rammed earth material in order to identify altered zones and to elaborate a methodology for the health diagnosis and the control of restoration. The ultrasonic surface measurements using a Pundit 54 KHz on chosen panels has led to construct P-wave velocities tomograms. The use of other waveform attributes such as the signal amplitude allowed studying the attenuation and loss of energy related to weathering. The application of the conventional Schmidt hammer test allowed to establish maps of the rebound values R and to assess the mechanical hardness of the raw and the restored panels. These methodologies are well known and applied to concrete, but still not adapted to earth material (pise). The mean idea is to combine both techniques to estimate a compressive strength through nondestructive tests, and at the end contributing to elaborate a kind of standardized charts. These prelimin...
Volublis’deki Roma mozaikleri opus tessellatum tipindedir. Bu mozaikler, Lacunae duzeninde (tesse... more Volublis’deki Roma mozaikleri opus tessellatum tipindedir. Bu mozaikler, Lacunae duzeninde (tesserae eksikligi) belirtilenden farkli bir bozulma ozelligi gostermekte olup mozaik dosemeleri catlaklarla ve kirilmalarla bozu- lur. Tessellatum’un bozulmasi ve catlaklarin duzeni mozaigi tasiyan topraktaki kabarmalarla iliskilidir. Ayrica, doseme tesserae aralarinda ve altinda bulunan ve onlara onemli derecede gozeneklilik veren ve tessellatumun kolayca cokmesine sebep olan ince taneli harctaki (ince taneli kirec ve kuvars) kimyasal bozulmalar nedeniyle de zarar gorebilir. Kimyasal cozunmeden dolayi kabarcik olusumu gosteren kirectasi tesseranin disinda, mer- mer ve cam tesseralar kotu havadan asinmalara karsi direnc gostermektedir
International journal of engineering research and technology, 2013
In Zeida abandoned mine, huge amount of mining dams were left without any adjustment and remediat... more In Zeida abandoned mine, huge amount of mining dams were left without any adjustment and remediation. Their exposition leads to mass erosion and transport over large distance in the watershed. Chemical analysis of these wastes show high contamination by heavy metals especially in fine grain size fraction. The leachate of wastes leads to the contamination of pit lake waters, the low content of Pb and Zn in the most sampled lakes is related to their low mobility in alkaline solution and their adsorption by clay and iron hydroxides. While high values recorded in As are attributed to its methylation by organic matter. Stream sediments show high contamination due to their location downstream the mining districts.
Journal of Environmental and Engineering Geophysics, 2020
The tailings of Zeida's abandoned mine are found near the city of Midelt, in the middle of th... more The tailings of Zeida's abandoned mine are found near the city of Midelt, in the middle of the high Moulouya watershed between the Middle and the High Atlas of Morocco. The tailings occupy an area of about 100 ha and are stored either in large mining pit lakes with clay-marl substratum or directly on a heavily fractured granite bedrock. The high contents of lead and arsenic in these tailings have transformed them into sources of pollution that disperse by wind, runoff, and seepage to the aquifer through faults and fractures. In this work, the main goal is to identify the pathways of contaminated water with heavy metals and arsenic to the local aquifers, water ponds, and Moulouya River. For this reason, geophysical surveys including electrical resistivity tomography (ERT), seismic refraction tomography (SRT) and very low-frequency electromagnetic (VLF-EM) methods were carried out over the tailings, and directly on the substratum outside the tailings. The result obtained from comb...
In the Zeida abandoned mine, pit lake waters exhibit alkaline pH and high conductivity. The conce... more In the Zeida abandoned mine, pit lake waters exhibit alkaline pH and high conductivity. The concentrations of the total dissolved lead and zinc are very low due to their adsorption on clay minerals and iron oxyhydroxides. Conversely, arsenic concentrations in two lakes (ZL1 and ZA) exceed WHO water quality guidelines. The As content is relatively high in ZL1 and exists mainly as As(V). In ZA, As(III) occurs in low concentration compared to the total dissolved arsenic, while dimethylarsenic acid (H2AsO2(CH3)2, DMA) prevails. This means that arsenic was methylated by organic matter produced by micro-organisms such as chlorella. The sequential extraction of floor sediments in the two lakes shows that the bioavailable arsenic contents change between them. In ZA, the sediments show high concentrations of lead and arsenic compared to the ZL1 sediment since it is surrounded by mining waste tailings, which are rich in these elements. An arsenic leaching test of ZA sediment shows that bioava...
Journal of Environmental and Engineering Geophysics, 2017
The abandoned lead mine of Zeida is located at the center of the High Moulouya watershed between ... more The abandoned lead mine of Zeida is located at the center of the High Moulouya watershed between the Middle and the High Atlas Mountains of Morocco. Zeida has produced a total of 640,000 tons of concentrated lead during the 14 years of its activity (1972–1985). Three large tailings were left at the center of the mine on both sides of Moulouya River without any risk reduction measures or monitoring and there is a concern regarding heavy metal contamination of local groundwater. Samples taken from and around the tailings were found to contain average lead and zinc concentrations of 3,000 ppm and 140 ppm, respectively, primarily in the form of galena and barite. Prior studies have also found high concentrations of lead and zinc in both local wells near the town of Zeida and along the banks of Moulouya River. In this study, five electrical resistivity imaging surveys were performed to identify the risk of pollution and trace the pathways of mine-based contaminants to groundwater and to ...
The objective of this study is to conduct a mineralogical and chemical characterization of the mo... more The objective of this study is to conduct a mineralogical and chemical characterization of the mortars Roman archaeological site of Volubilis to rebuild spare mortars for restoration. We take samples of mortar, broken tile palate garden, and pavement mosaic Falavius Germanus houses. The analysis by X-ray diffraction reveals the coarse mortar Flavius Germanus is made of quartz and calcite with feldspar and probably, mica and dolomite in small amounts. The binder end is formed calcite and quartz. However, the broken tile mortar is formed by coarse particles, clay base mixed with a binder phase dominated by calcite. These results allowed us to reformulate spare mortars for the restoration of damaged Roman mosaics. The mortars are made up by 63.6% of lime and 36.4% of sand(with 4.19% of large grain, 71, 04% of coarse sand, 24.22%, of fine sand and 0.55% fines parts).The performance of these mortars was tested by mechanical testing.
In the abandoned mine in Zaida, the pit lakes filled with water constitute significant water rese... more In the abandoned mine in Zaida, the pit lakes filled with water constitute significant water reserves. In these lakes, the waters are permanently in contact with ore deposit (cerussite and galena). The modelling of the interaction of waters with this mineralization shows that cerussite dissolves more rapidly than galena. This dissolution is controlled by the pH and dissolved oxygen concentration in solution. The lead concentrations recorded in these lakes come largely from the dissolution of cerussite.
Uploads
Papers by ABDELILAH DEKAYIR