I am full professor in civil engineering and architecture. I’m a professional too in building practices. Specialist of housing. Decision system support.
International journal of advanced research, Aug 31, 2021
Soil is a widespread natural resource. It comes from the degradation of the mother rock, followin... more Soil is a widespread natural resource. It comes from the degradation of the mother rock, following the phenomenon of climatic and chemical erosion. Therefore, all soils have very different characteristics depending on their origin [1,2]. Today it is estimated that more than one third of the worlds population lives in earthen housing [3]. In view of the advantages offered by the earth material, several developing countries have adopted the raw earth construction in order to face the housing crisis that is intensifying nowadays. Among the advantages of raw earth, we can highlight the low energy required for its implementation, its aesthetic qualities and good thermal inertia, which allows a cool habitat in summer and retains heat in winter. But the problem with earthen constructions is that they suffer from a lack of resistance, systematic cracking due to shrinkage and problems related to their sensitivity to water [4]. From ancient times to the present day, man has sought to avoid the disadvantages of the earth material, using several means of stabilization to improve its performance and its sensitivity to water, which has given rise to several earth products: adobe, adobe, cob, compressed earth block (CEB) and others. Stabilizing the earth is to give it the properties reversible against physical stresses [5], it is currently confirmed that the stabilization of CEB by binders and bitumen improves their mechanical resistance and insensitivity to water [6]. Thus, scientific studies have been conducted on the stabilization of raw earth by mineral binders (cement and lime) for the most part [7] and by fibers (animal, vegetable and synthetic). However, the use of these mineral binders in high proportions may call into question the ecological character of the material [8]. The knowledge of the physical characteristics of lateritic soils is very important for their better use in the manufacture of compressed and stabilized earth blocks. Some social strata for the manufacture of CEB use lateritic soils without control of their physical characteristics, which leads to consequences such as progressive crumbling of walls, cracks, poor performance of plasters, and discouragement of the use of the said technology. In this study we intend to compile the most reliable experimental data on the physical properties of natural earth and the mechanical properties of CEB. We will take inventory of the performances determined in previous works by several research teams regarding the characterization and stabilization of lateritic soils to be used in the manufacture of CEB. We will give an overview of the state of knowledge concerning the different properties (physical, mechanical and hygrometric properties). Finally, a literature review will also give some orientations for future scientific research.
International journal of digital innovation in the built environment, 2021
Recent research reveals a surge in the number of slums in Sub-Saharan Africa with no sign of abat... more Recent research reveals a surge in the number of slums in Sub-Saharan Africa with no sign of abating. Thus, the upgrading of slums to improve the living conditions of those who live in such environments is imperative. However, the performance of past slum upgrading projects has been quite contentious with many failing to meet their pre-defined objectives. This study investigates the influence of integrated BIM and M&E on the performance of slum upgrading projects in Sub-Saharan Africa. A questionnaire was used to gather data from 88 M&E and BIM experts. It emerged that on average 68.6% “Agreed and Strongly Agreed” that integrating both M&E and BIM can significantly improve the performance of slum upgrading projects compared to each when applied in isolation. Consequently, future studies should focus on developing an integrated BIM and M&E framework for monitoring slum upgrading projects.
The problems of supplying African cities with potable water and electricity are characterised by ... more The problems of supplying African cities with potable water and electricity are characterised by uneven capacities of the networks, inefficiencies of supply, low subscription rates and low rates of return. This paper proposes ways of improving access rates of city dwellers to potable water and electricity without reducing the technical and commercial efficiencies of network managers. The main innovation consists
International journal of advanced research, Aug 31, 2021
Soil is a widespread natural resource. It comes from the degradation of the mother rock, followin... more Soil is a widespread natural resource. It comes from the degradation of the mother rock, following the phenomenon of climatic and chemical erosion. Therefore, all soils have very different characteristics depending on their origin [1,2]. Today it is estimated that more than one third of the worlds population lives in earthen housing [3]. In view of the advantages offered by the earth material, several developing countries have adopted the raw earth construction in order to face the housing crisis that is intensifying nowadays. Among the advantages of raw earth, we can highlight the low energy required for its implementation, its aesthetic qualities and good thermal inertia, which allows a cool habitat in summer and retains heat in winter. But the problem with earthen constructions is that they suffer from a lack of resistance, systematic cracking due to shrinkage and problems related to their sensitivity to water [4]. From ancient times to the present day, man has sought to avoid the disadvantages of the earth material, using several means of stabilization to improve its performance and its sensitivity to water, which has given rise to several earth products: adobe, adobe, cob, compressed earth block (CEB) and others. Stabilizing the earth is to give it the properties reversible against physical stresses [5], it is currently confirmed that the stabilization of CEB by binders and bitumen improves their mechanical resistance and insensitivity to water [6]. Thus, scientific studies have been conducted on the stabilization of raw earth by mineral binders (cement and lime) for the most part [7] and by fibers (animal, vegetable and synthetic). However, the use of these mineral binders in high proportions may call into question the ecological character of the material [8]. The knowledge of the physical characteristics of lateritic soils is very important for their better use in the manufacture of compressed and stabilized earth blocks. Some social strata for the manufacture of CEB use lateritic soils without control of their physical characteristics, which leads to consequences such as progressive crumbling of walls, cracks, poor performance of plasters, and discouragement of the use of the said technology. In this study we intend to compile the most reliable experimental data on the physical properties of natural earth and the mechanical properties of CEB. We will take inventory of the performances determined in previous works by several research teams regarding the characterization and stabilization of lateritic soils to be used in the manufacture of CEB. We will give an overview of the state of knowledge concerning the different properties (physical, mechanical and hygrometric properties). Finally, a literature review will also give some orientations for future scientific research.
International journal of digital innovation in the built environment, 2021
Recent research reveals a surge in the number of slums in Sub-Saharan Africa with no sign of abat... more Recent research reveals a surge in the number of slums in Sub-Saharan Africa with no sign of abating. Thus, the upgrading of slums to improve the living conditions of those who live in such environments is imperative. However, the performance of past slum upgrading projects has been quite contentious with many failing to meet their pre-defined objectives. This study investigates the influence of integrated BIM and M&E on the performance of slum upgrading projects in Sub-Saharan Africa. A questionnaire was used to gather data from 88 M&E and BIM experts. It emerged that on average 68.6% “Agreed and Strongly Agreed” that integrating both M&E and BIM can significantly improve the performance of slum upgrading projects compared to each when applied in isolation. Consequently, future studies should focus on developing an integrated BIM and M&E framework for monitoring slum upgrading projects.
The problems of supplying African cities with potable water and electricity are characterised by ... more The problems of supplying African cities with potable water and electricity are characterised by uneven capacities of the networks, inefficiencies of supply, low subscription rates and low rates of return. This paper proposes ways of improving access rates of city dwellers to potable water and electricity without reducing the technical and commercial efficiencies of network managers. The main innovation consists
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