The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas gree...The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas greenhouse,etc.).In order to meet the challenges of sustainable development,earth construction is experiencing a resurgence of interest these days.Despite its many advantages,raw earth material has drawbacks,in particular its low mechanical resistance and its loss of geometric characteristics in the face of water,which slow down its development.As part of this study,the mechanical characteristics and durability of raw earth were improved by using residual water from the processing of Parkia Biglobosa(nere)and Vitellaria Paradoxa(shea)nuts in order to optimize its use for the construction of modern buildings.To this end,the decoctions resulting from the artisanal transformation of the nut of the Parkia Biglobosa into African mustard and of the Vitellaria Paradoxa into shea butter were added to the raw earth according to volume proportions of 25%,50%,75%and 100%of the aqueous solution to obtain the projected composites.Thus,mechanical characterization and durability tests were carried out on the composites obtained.The results revealed that the decoctions of Vitellaria Paradoxa and Parkia Biglobosa improve the compressive strength of the material by up to 90%and 260%,respectively.Furthermore,these decoctions improved the resistance to water penetration of the 100%additive composite by 1.5 times for Vitellaria Paradoxa and 5 times for Parkia Biglobosa.This study shows that it is possible to use decoctions as raw earth stabilizers to build modern,ecological buildings at lower energy costs.However,more in-depth studies on surface wettability and long-term durability are planned to better characterize the geomaterial.展开更多
In tropical areas,palm oil production generates significant amounts of waste,including palm kernel shells.The use of this waste in the civil engineering sector,presents a very challenging task.In the present study,the...In tropical areas,palm oil production generates significant amounts of waste,including palm kernel shells.The use of this waste in the civil engineering sector,presents a very challenging task.In the present study,the production of lateritic soil(A-2 in GTR classification and A-7-6(9)in HRB classification)reinforced with palm kernel shells is considered.In order to improve their performances,these materials are mixed using the Fuller’s parabolic law.Moreover,experimental tests are used to characterize the physical and mechanical geotechnical properties of the lateritic soil.After characterizing the matrix(i.e.,lateritic soil)and the inclusions(i.e.,palm kernel shells)in their natural state,it is found that Avrankou’s lateritic soil has a high level of fine particles(56.6%),high plasticity(PI=21%)and low lift(ICBR=17%);which makes it unusable in the pavement layer.Results also prove that the mixture composed of 39%of lateritic soil volume and 61%of PKS with a CBR index equals to 30 and the mixture composed of 45%of lateritic soil,40%PKS and 15%of lagoon sand with a CBR index equals to 41 can be used as sub-base layer for roads for low and medium traffic,respectively.展开更多
To contribute to the enhancement of unconventional local materials used for road construction,this study characterizes a crushed sand 0/5,a clayey soil and the litho-stabilized material without and with hydraulic bind...To contribute to the enhancement of unconventional local materials used for road construction,this study characterizes a crushed sand 0/5,a clayey soil and the litho-stabilized material without and with hydraulic binder and determines their use in accordance with some reference specifications(CEBTP 1984).It is shown that the different components are not usable alone in pavement base.Indeed,the plasticity index obtained for the clayey soil is 21%,a value higher than the imposed standards.In addition,the grading of the 0/5 crushed sand does not fit into the range proposed by CEBTP.A combination of these two(02)components is therefore considered to obtain a suitable material usable for the sub-base.This new material does not enter any class of the CEBTP lateritic soils.In order to be used in base layer,a treatment with hydraulic binder is carried out with the intention to improve its mechanical performances.The optimal dosage of hydraulic binder to achieve the desired mechanical performance is obtained by studying the evolution of the mechanical characteristics of the mixture.After this treatment,the Bearing Ratio index of the mix increases from 37 to 223 for the optimal dosage and the dry compaction density decreases from 2.11 to 2.06 g/cm3 while the optimal water content increases from 9%to 10.1%.展开更多
基金supported by the Beninese state.An author received a trainer training grant from the Benin state for stays in the Jean Lamour Institute Laboratory of the University of Lorraine in France to carry out tests.
文摘The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas greenhouse,etc.).In order to meet the challenges of sustainable development,earth construction is experiencing a resurgence of interest these days.Despite its many advantages,raw earth material has drawbacks,in particular its low mechanical resistance and its loss of geometric characteristics in the face of water,which slow down its development.As part of this study,the mechanical characteristics and durability of raw earth were improved by using residual water from the processing of Parkia Biglobosa(nere)and Vitellaria Paradoxa(shea)nuts in order to optimize its use for the construction of modern buildings.To this end,the decoctions resulting from the artisanal transformation of the nut of the Parkia Biglobosa into African mustard and of the Vitellaria Paradoxa into shea butter were added to the raw earth according to volume proportions of 25%,50%,75%and 100%of the aqueous solution to obtain the projected composites.Thus,mechanical characterization and durability tests were carried out on the composites obtained.The results revealed that the decoctions of Vitellaria Paradoxa and Parkia Biglobosa improve the compressive strength of the material by up to 90%and 260%,respectively.Furthermore,these decoctions improved the resistance to water penetration of the 100%additive composite by 1.5 times for Vitellaria Paradoxa and 5 times for Parkia Biglobosa.This study shows that it is possible to use decoctions as raw earth stabilizers to build modern,ecological buildings at lower energy costs.However,more in-depth studies on surface wettability and long-term durability are planned to better characterize the geomaterial.
文摘In tropical areas,palm oil production generates significant amounts of waste,including palm kernel shells.The use of this waste in the civil engineering sector,presents a very challenging task.In the present study,the production of lateritic soil(A-2 in GTR classification and A-7-6(9)in HRB classification)reinforced with palm kernel shells is considered.In order to improve their performances,these materials are mixed using the Fuller’s parabolic law.Moreover,experimental tests are used to characterize the physical and mechanical geotechnical properties of the lateritic soil.After characterizing the matrix(i.e.,lateritic soil)and the inclusions(i.e.,palm kernel shells)in their natural state,it is found that Avrankou’s lateritic soil has a high level of fine particles(56.6%),high plasticity(PI=21%)and low lift(ICBR=17%);which makes it unusable in the pavement layer.Results also prove that the mixture composed of 39%of lateritic soil volume and 61%of PKS with a CBR index equals to 30 and the mixture composed of 45%of lateritic soil,40%PKS and 15%of lagoon sand with a CBR index equals to 41 can be used as sub-base layer for roads for low and medium traffic,respectively.
文摘To contribute to the enhancement of unconventional local materials used for road construction,this study characterizes a crushed sand 0/5,a clayey soil and the litho-stabilized material without and with hydraulic binder and determines their use in accordance with some reference specifications(CEBTP 1984).It is shown that the different components are not usable alone in pavement base.Indeed,the plasticity index obtained for the clayey soil is 21%,a value higher than the imposed standards.In addition,the grading of the 0/5 crushed sand does not fit into the range proposed by CEBTP.A combination of these two(02)components is therefore considered to obtain a suitable material usable for the sub-base.This new material does not enter any class of the CEBTP lateritic soils.In order to be used in base layer,a treatment with hydraulic binder is carried out with the intention to improve its mechanical performances.The optimal dosage of hydraulic binder to achieve the desired mechanical performance is obtained by studying the evolution of the mechanical characteristics of the mixture.After this treatment,the Bearing Ratio index of the mix increases from 37 to 223 for the optimal dosage and the dry compaction density decreases from 2.11 to 2.06 g/cm3 while the optimal water content increases from 9%to 10.1%.