The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compoun...The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compound as an insulating eco-material in building in a tropical climate. The composites samples were developed by mixing plaster with raffia vinifera particles (RVP) using three different sizes (1.6 mm, 2.5 mm and 4 mm). The effects of four different RVP incorporations rates (i.e., 0wt%, 5wt%;10wt%;15wt%) on physical, thermal, mechanicals properties of the composites were investigated. In addition, the use of the raffia vinifera particles and plaster based composite material as building envelopes thermal insulation material is studied by the habitable cell thermal behavior instrumentation. The results indicate that the incorporation of raffia vinifera particle leads to improve the new composite physical, mechanical and thermal properties. And the parametric analysis reveals that the sampling rate and the size of raffia vinifera particles are the most decisive factor to impact these properties, and to decreases in the thermal conductivity which leads to an improvement to the thermal resistance and energy savings. The best improvement of plaster composite was obtained at the raffia vinifera particles size between 2.5 and 4.0 mm loading of 5wt% (C95P5R) with a good ratio of thermo-physical-mechanical properties. Additionally, the habitable cell experimental thermal behavior, with the new raffia vinifera particles and plaster-based composite as thermal insulating material for building walls, gives an average damping of 4°C and 5.8°C in the insulated house interior environment respectively for cold and hot cases compared to the outside environment and the uninsulated house interior environment. The current study highlights that this mixture gives the new composite thermal insulation properties applicable in the eco-construction of habitats in tropical environments.展开更多
This experimental study aims at the reuse of recycled aggregates (RA), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. The RA can r...This experimental study aims at the reuse of recycled aggregates (RA), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. The RA can readily replace natural aggregates in concrete. Then five formulations of natural and recycled aggregates based concrete for characteristic strength of 25 Mpa were prepared in addition to the natural aggregates base concrete named reference concrete (BN): two types of recycled aggregates concrete (BR), three types of recycles and natural combined aggregates base concrete (BC). The properties of natural and recycled aggregates were characterized and the physical, mechanical strength and durability properties were also evaluated for all concrete specimens. All the studied concrete formulation present a density between 2000 kg/m<sup>3</sup> ≤ ρ ≥ 2600 kg/m<sup>3</sup> and an average slump of 4.9 ± 0.1 cm. The obtained results indicate that the recycled aggregates are suitable for current concrete. Two out of the five combinations studied, such as the natural (BN) and combined aggregate (BC2) based concretes satisfy the mechanical characteristics (Rc<sub>28</sub> > 25 MPa) at 28 days of age and an average absorption coefficient of 2.93% and 3.98%. The recycled aggregate based concrete (BR1, BR2) and combined aggregate based concrete (BC1), gave respective average compressive strength of 21.55 MPa, 20.50 MPa and 20.30 MPa, i.e. a difference of 13.80% to 18.80% under the characteristic strength (25 MPa) aimed at 28 days of age. Thus, the recycled aggregates are in conformity with the normative prescriptions and their use for standard concrete gives adequate physical, mechanical and durability properties for the production of the C20/25 concrete series in the common civil engineering applications.展开更多
The present study allowed to carry out a thermal characterization of concrete and cement mortar. Thermal tests were carried out with the KD2 Pro device, on concrete and mortar samples taken from twenty-six (26) constr...The present study allowed to carry out a thermal characterization of concrete and cement mortar. Thermal tests were carried out with the KD2 Pro device, on concrete and mortar samples taken from twenty-six (26) construction sites of office buildings and two (2) industrial production units in the city of Ouagadougou. The tests were carried out on rectangular specimens after four weeks (4) of conservation on the site of construction or production of materials. This study seeks to determine the thermal properties of the materials, in particular the thermal conductivity, the thermal diffusivity and the thermal capacity of the samples, in the real conditions of execution of the buildings and environment. The thermal conductivity varies from 1.413 to 1.965 W/m·K, 0.940 - 1.658 W/m·K and 0.703 - 1.149 W/m·K respectively for concrete, cinder block mortar and plaster mortar. Regarding the other properties, especially the capacity and thermal diffusivity, the values vary respectively, from 1070.59 - 1974.67 kJ/kg·K and (3.74 - 6.70) × 10-7</sup> m2</sup>/s for concrete, from 1123.69 - 1586.81 kJ/kg·K and (3.38 - 5.65) × 10<sup>-</sup>7</sup> m2</sup>/s for plaster mortar and 1202.51 - 1736.01 kJ/kg·K and (3.82 - 7.36) × 10-7</sup> m2</sup>/s for the mortar of building blocks. The conductivity, capacity and thermal diffusivity of industrial mortar vary from 1.019 - 1.229 W/m·K, 792.18 - 1862.58 J/kg·K and (2.75 - 6.80) × 10-7</sup> m2</sup>/s, respectively. Only the correlations made between the thermal properties and the density of the samples of the plaster mortar, give good relations namely R2</sup> = 0.9308 for the thermal conductivity, R2</sup> = 0.7823 for the thermal capacity and R2</sup> = 0.9272 for the thermal diffusivity. This study contributes to the establishment of a thermal regulation in Burkina Faso for the adoption of the West African Economic and Monetary Union (WAEMU) Directive 05 on energy efficiency in buildings.展开更多
Living in a habitat with comfort is requested by all. Cinder block bricks have poor thermal properties, leading people to use fan heaters and air conditioners to regain comfort. To overcome this problem of thermal dis...Living in a habitat with comfort is requested by all. Cinder block bricks have poor thermal properties, leading people to use fan heaters and air conditioners to regain comfort. To overcome this problem of thermal discomfort in buildings, we used lightweight concrete such as foamed concrete which is a material that has improved thermal properties for thermal comfort. In addition, this material was compared with local materials used for the construction of buildings such as BTC, adobe and BLT mixed with binders. The results showed that foamed concrete is a material that has good thermal and mechanical properties compared to local materials mixed with binders. The foamed concrete having acceptable thermo-mechanical properties was that having a density of 930 kg/m<sup>3</sup>. It has a thermal resistance of 0.4 m<sup>2</sup>·K/W for a thickness of 20 cm. The foamed concrete having acceptable thermo-mechanical properties was that having a density of 930 kg/m3</sup>. It has a thermal resistance of 0.4 m2</sup>·K/W for a thickness of 20 cm. For sunshine on a daily cycle equal to 12 hours, the characteristic thickness achieved by this material is 7.29 cm. It also has a shallow depth of heat diffusion having a lower thickness than other materials. This shows that foamed concrete is a promising material for the construction of buildings.展开更多
文摘The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compound as an insulating eco-material in building in a tropical climate. The composites samples were developed by mixing plaster with raffia vinifera particles (RVP) using three different sizes (1.6 mm, 2.5 mm and 4 mm). The effects of four different RVP incorporations rates (i.e., 0wt%, 5wt%;10wt%;15wt%) on physical, thermal, mechanicals properties of the composites were investigated. In addition, the use of the raffia vinifera particles and plaster based composite material as building envelopes thermal insulation material is studied by the habitable cell thermal behavior instrumentation. The results indicate that the incorporation of raffia vinifera particle leads to improve the new composite physical, mechanical and thermal properties. And the parametric analysis reveals that the sampling rate and the size of raffia vinifera particles are the most decisive factor to impact these properties, and to decreases in the thermal conductivity which leads to an improvement to the thermal resistance and energy savings. The best improvement of plaster composite was obtained at the raffia vinifera particles size between 2.5 and 4.0 mm loading of 5wt% (C95P5R) with a good ratio of thermo-physical-mechanical properties. Additionally, the habitable cell experimental thermal behavior, with the new raffia vinifera particles and plaster-based composite as thermal insulating material for building walls, gives an average damping of 4°C and 5.8°C in the insulated house interior environment respectively for cold and hot cases compared to the outside environment and the uninsulated house interior environment. The current study highlights that this mixture gives the new composite thermal insulation properties applicable in the eco-construction of habitats in tropical environments.
文摘This experimental study aims at the reuse of recycled aggregates (RA), resulting from the demolition of concrete, cement block and cement mortar, in the manufacture of common construction in Burkina Faso. The RA can readily replace natural aggregates in concrete. Then five formulations of natural and recycled aggregates based concrete for characteristic strength of 25 Mpa were prepared in addition to the natural aggregates base concrete named reference concrete (BN): two types of recycled aggregates concrete (BR), three types of recycles and natural combined aggregates base concrete (BC). The properties of natural and recycled aggregates were characterized and the physical, mechanical strength and durability properties were also evaluated for all concrete specimens. All the studied concrete formulation present a density between 2000 kg/m<sup>3</sup> ≤ ρ ≥ 2600 kg/m<sup>3</sup> and an average slump of 4.9 ± 0.1 cm. The obtained results indicate that the recycled aggregates are suitable for current concrete. Two out of the five combinations studied, such as the natural (BN) and combined aggregate (BC2) based concretes satisfy the mechanical characteristics (Rc<sub>28</sub> > 25 MPa) at 28 days of age and an average absorption coefficient of 2.93% and 3.98%. The recycled aggregate based concrete (BR1, BR2) and combined aggregate based concrete (BC1), gave respective average compressive strength of 21.55 MPa, 20.50 MPa and 20.30 MPa, i.e. a difference of 13.80% to 18.80% under the characteristic strength (25 MPa) aimed at 28 days of age. Thus, the recycled aggregates are in conformity with the normative prescriptions and their use for standard concrete gives adequate physical, mechanical and durability properties for the production of the C20/25 concrete series in the common civil engineering applications.
文摘The present study allowed to carry out a thermal characterization of concrete and cement mortar. Thermal tests were carried out with the KD2 Pro device, on concrete and mortar samples taken from twenty-six (26) construction sites of office buildings and two (2) industrial production units in the city of Ouagadougou. The tests were carried out on rectangular specimens after four weeks (4) of conservation on the site of construction or production of materials. This study seeks to determine the thermal properties of the materials, in particular the thermal conductivity, the thermal diffusivity and the thermal capacity of the samples, in the real conditions of execution of the buildings and environment. The thermal conductivity varies from 1.413 to 1.965 W/m·K, 0.940 - 1.658 W/m·K and 0.703 - 1.149 W/m·K respectively for concrete, cinder block mortar and plaster mortar. Regarding the other properties, especially the capacity and thermal diffusivity, the values vary respectively, from 1070.59 - 1974.67 kJ/kg·K and (3.74 - 6.70) × 10-7</sup> m2</sup>/s for concrete, from 1123.69 - 1586.81 kJ/kg·K and (3.38 - 5.65) × 10<sup>-</sup>7</sup> m2</sup>/s for plaster mortar and 1202.51 - 1736.01 kJ/kg·K and (3.82 - 7.36) × 10-7</sup> m2</sup>/s for the mortar of building blocks. The conductivity, capacity and thermal diffusivity of industrial mortar vary from 1.019 - 1.229 W/m·K, 792.18 - 1862.58 J/kg·K and (2.75 - 6.80) × 10-7</sup> m2</sup>/s, respectively. Only the correlations made between the thermal properties and the density of the samples of the plaster mortar, give good relations namely R2</sup> = 0.9308 for the thermal conductivity, R2</sup> = 0.7823 for the thermal capacity and R2</sup> = 0.9272 for the thermal diffusivity. This study contributes to the establishment of a thermal regulation in Burkina Faso for the adoption of the West African Economic and Monetary Union (WAEMU) Directive 05 on energy efficiency in buildings.
文摘Living in a habitat with comfort is requested by all. Cinder block bricks have poor thermal properties, leading people to use fan heaters and air conditioners to regain comfort. To overcome this problem of thermal discomfort in buildings, we used lightweight concrete such as foamed concrete which is a material that has improved thermal properties for thermal comfort. In addition, this material was compared with local materials used for the construction of buildings such as BTC, adobe and BLT mixed with binders. The results showed that foamed concrete is a material that has good thermal and mechanical properties compared to local materials mixed with binders. The foamed concrete having acceptable thermo-mechanical properties was that having a density of 930 kg/m<sup>3</sup>. It has a thermal resistance of 0.4 m<sup>2</sup>·K/W for a thickness of 20 cm. The foamed concrete having acceptable thermo-mechanical properties was that having a density of 930 kg/m3</sup>. It has a thermal resistance of 0.4 m2</sup>·K/W for a thickness of 20 cm. For sunshine on a daily cycle equal to 12 hours, the characteristic thickness achieved by this material is 7.29 cm. It also has a shallow depth of heat diffusion having a lower thickness than other materials. This shows that foamed concrete is a promising material for the construction of buildings.
