References of "Courard, Luc"
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See detailSimulation of humidity and temperature distribution in green roof with pozzolana as drainage layer: influence of outdoor seasonal weather conditions and internal ceiling temperature
Kazemi, Mostafa ULiege; Courard, Luc ULiege

in Science and Technology for the Built Environment (2021)

The outdoor seasonal weather conditions can influence the insulation performance of extensive green roof. In addition, the thermal behavior of extensive green roof can be affected by the thickness of its ... [more ▼]

The outdoor seasonal weather conditions can influence the insulation performance of extensive green roof. In addition, the thermal behavior of extensive green roof can be affected by the thickness of its layers including substrate and drainage layer. On the other hand, the replacement of polyethylene modular panel with porous aggregates as drainage layer can affect the water retention capacity of green roof. Therefore, in this study, the green roofs with pozzolana (porous volcanic gravel) as drainage layer under constant and variable inside temperatures were modeled and subjected to the weather conditions of winter and summer to assess the humidity and temperature variations in the depth of the systems. The results showed that there was a decrease in temperature through the depth of the green roof system for the winter period, while the reverse occurred for the relative humidity. During the winter period, the green roof model with the 10-cm substrate and 8-cm pozzolana was recommended to be used. However, the model with the 8-cm substrate and 6-cm drainage layer had the best insulation performance, particularly for the summer period. Moreover, the internal ceiling temperature fluctuation of system under variable inside temperature was higher than that under constant inside temperature. [less ▲]

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See detailInfluence of hydrophobic product nature and concentration on carbonation resistance of cultural heritage concrete buildings
Courard, Luc ULiege; Zhao, Zengfeng ULiege; Michel, Frédéric ULiege

in Cement and Concrete Composites (2021), 115

The concrete based patrimony is subjected to different deterioration mechanisms, including steel corrosion induced by carbonation or chloride ion diffusion. Hydrophobic product may be used for protecting ... [more ▼]

The concrete based patrimony is subjected to different deterioration mechanisms, including steel corrosion induced by carbonation or chloride ion diffusion. Hydrophobic product may be used for protecting concrete structures against water ingress. No data are available on the correlation between quality of hydrophobic agent, concrete substrate properties and carbonation resistance. The influence of hydrophobic product and water to cement ratio of concrete substrate on the carbonation resistance has been investigated. The results show that there is a clear effect of hydrophobic treatment on carbonation resistance as well as chloride diffusion, specifically for high active product concentration and high W/C ratio. [less ▲]

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See detailIntra-granular porosity of grinded hardened cement paste and bricks: modeling and experimentation.
Bouarroudj, Mohamed El Karim; Remond, Sébastien; Grellier, Adèle ULiege et al

in Materials and Structures (2021), 54(88),

Recycled concrete aggregate (RCA) possess high water absorption, due to the porosity of the attached hardened cement paste they contain. Fine particles of RCA are composed of larger amounts of hardened ... [more ▼]

Recycled concrete aggregate (RCA) possess high water absorption, due to the porosity of the attached hardened cement paste they contain. Fine particles of RCA are composed of larger amounts of hardened cement paste, which makes their valorization even more difficult in concrete or mortar. One way to valorize these fine particles could be to use them as mineral addition, however their water absorption coefficient has to be determined, which is tricky for powders. The objective of this work is to estimate the remaining intra granular porosity of a ground powder using two different original approaches. The first modelling approach considers that the porous monolith material is composed of series of pores with characteristic volumes. A pore is considered opened due to grinding if it is cut by the surface of the particle and if its size is larger than the smallest inter granular pore. The remaining porosity after grinding is computed from the pore size distribution of the monolith material and the particle size distribution of the powder. The second experimental approach is based on mercury intrusion porosimetry tests performed on the powder. The separation between inter and intra granular porosity allows the estimation of the powder’s remaining porosity. The obtained results show a good agreement between the two approaches in the case of disconnected pores. However, in the case of connected porosity, the experimental approach over estimates the amount of inter-granular porosity. [less ▲]

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See detailRapport scientifique et technique final - Partenaire ULiège-GeMMe
Courard, Luc ULiege; Hubert, Julien ULiege; Zhao, Zengfeng ULiege et al

Report (2021)

Dans ce rapport final, nous avons choisi de présenter les résultats en fonction des produits testés (et non des tâches). Les travaux de recherche présentés dans ce rapport sont exposés en trois chapitres ... [more ▼]

Dans ce rapport final, nous avons choisi de présenter les résultats en fonction des produits testés (et non des tâches). Les travaux de recherche présentés dans ce rapport sont exposés en trois chapitres : 1. le premier chapitre traite des cendres volantes de charbon et des cendres volantes de biomasse ; 2. le deuxième chapitre décrit les travaux de recherche réalisés sur les granulats recyclés de béton, notamment en combinaison avec des fillers calcaires pour la formulation de bétons ; 3. le troisième chapitre porte sur la caractérisation des granulats recyclés de mâchefers d’incinérateur d’ordures ménagères (MIOM) et sur la formulation de bétons. [less ▲]

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See detailNumerical Modelling Approach for UHPFRC Members Including Crack Spacing Formulations
Franssen, Renaud ULiege; Guner, Serhan ULiege; Courard, Luc ULiege et al

in Engineering Structures (2021), 238

Ultra-high performance fiber-reinforced concrete (UHPFRC) possesses excellent mechanical properties and durability. The steel fibers in the concrete result in significant post-cracking tensile resistance ... [more ▼]

Ultra-high performance fiber-reinforced concrete (UHPFRC) possesses excellent mechanical properties and durability. The steel fibers in the concrete result in significant post-cracking tensile resistance and enhanced crack control. However, while UHPFRC is a promising material for the construction of new (and repair of existing) infrastructure, its application is still limited—in part due to the lack of numerical models with the capacity to simulate its complex behavior. To help overcome this challenge, this study proposes a numerical material modeling approach for the nonlinear finite element analysis of UHPFRC. The approach aims to provide a general applicability to model both shear- and flexure-critical members made from strain-softening or -hardening UHPFRC, while still using simple equations. This objective can be achieved by establishing a comprehensive set of crack spacing formulations and modeling recommendations to capture the unique behavior of UHPFRC. The crack spacing estimates are used together with the Diverse Embedment Model for FRC, which is extended here for the modeling of UHPFRC. When applied to 29 flexure- and shear-critical specimens, the proposed modeling approach accurately simulates the experimental responses with an average of 1.04 and a coefficient of variation of 10.2% for the experimental-to-predicted strength ratios. [less ▲]

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See detailHydric and Durability Performances of Compressed Earth Blocks Stabilized with Industrial and Agro By-Product Binders: Calcium Carbide Residue and Rice Husk Ash
Nshimiyimana, Philbert; Courard, Luc ULiege; Messan, Adamah

in Journal of Materials in Civil Engineering (2021), 33(6),

This study investigated the hydric and durability performances of compressed earth blocks (CEBs) stabilized with calcium carbide residue (CCR) and rice husk ash (RHA). Dry mixtures were prepared using ... [more ▼]

This study investigated the hydric and durability performances of compressed earth blocks (CEBs) stabilized with calcium carbide residue (CCR) and rice husk ash (RHA). Dry mixtures were prepared using kaolinite-rich earthen material and 0%–25% CCR or 20∶0% to 12∶8% CCR:RHA of the weight of the earth. Moistened mixtures were manually compressed to produce CEBs (295×140×95  mm). Stabilized CEBs were cured at 30°C±5°C and wrapped in plastic bags for 45 days. The cured CEBs were dried and tested for water absorption and other indicators of durability. Unstabilized CEBs immediately degraded in water. The stabilized CEBs were stable in water, with a very low coefficient of capillary absorption (<20  g/cm2⋅min1/2) and excellent durability indicators. They resisted erosion at a standard water pressure (50 kPa) and at a pressure of 500 kPa. The coefficient of surface abrasion improved far higher than the 7  cm2/g recommended for the construction of facing masonry. It also increased after wetting-drying cycles and correlated with the evolution of compressive strength. This correlation can be used as the nondestructive test of stabilized CEBs. [less ▲]

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See detailConstruction en terre, ressources secondaires et matériaux bio-sourcés: un avenir pour l’Afrique
Courard, Luc ULiege

in Bulletin des Séances de l'Académie Royale des Sciences d'Outre-Mer (2021)

Earth is both an ancestral and contemporary material for the construction of dwellings but also civil and religious buildings. As the population, especially across the African continent, continues to grow ... [more ▼]

Earth is both an ancestral and contemporary material for the construction of dwellings but also civil and religious buildings. As the population, especially across the African continent, continues to grow, finding quality, comfortable and sustainable housing is becoming increasingly difficult. The availability and high cost of building materials such as cement, steel or wood are limiting access to housing for a growing share of the population who crowd into slums. Reclaiming earth as a building material is a part of the solution. It is by improving its performance, through the use of secondary resources from industrial or agricultural by-products, that the architect and the engineer can convince the population that earth is and remains a material of the future. This reflection is illustrated specifically from the production of Compressed Earth Bricks (CEB), stabilized with residual lime and rice husk ash. [less ▲]

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See detailChallenging construction industry with C&DW: opportunities and limits
Courard, Luc ULiege; Zhao, Zengfeng ULiege; Hubert, Julien ULiege

in Revista Hormigon (2021), (H59), 33-45

Construction and Demolition Waste (C&DW) comprises the largest waste stream in the European Union (EU), with relatively stable amounts produced over time and high recovery rates: it is estimated at one ... [more ▼]

Construction and Demolition Waste (C&DW) comprises the largest waste stream in the European Union (EU), with relatively stable amounts produced over time and high recovery rates: it is estimated at one third of total wastes generated in the EU. Although this may suggest that the construction sector is highly circular, scrutiny of waste management practices reveals that C&DW recovery is largely based on backfilling operations and low-grade recovery, such as using recycled aggregates in road sub-bases. These wastes are usually recovered as secondary raw materials after a recycling process resulting in the production of recycled sands and aggregates. Researches have been performed to show how it is possible to encourage and support the use of these recycled materials: preparation process and selection are fundamental for increasing capability of recycling. Analysis of recycled bricks and tiles sands and fine particles has also been tested as substitution product in concrete design. A quantitative analysis is proposed for five North West European (NWE) countries: Belgium, France, Germany, Luxembourg and the Netherlands, where barriers are pointed out. The construction industry will be definitively affected by C&DW recycling for promoting circular economy in the coming years. [less ▲]

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See detailInternal sulfate attack in mortars containing contaminated fine recycled concrete aggregates
Colman, Charlotte ULiege; Bulteel, David; Thiery, Vincent et al

in Construction and Building Materials (2021), 272

Internal sulfate attack can be caused by the gypsum residues present in fine recycled aggregates (FRA). Asopposed to the better known external sulfate attack or Delayed Ettringite Formation (DEF), the ... [more ▼]

Internal sulfate attack can be caused by the gypsum residues present in fine recycled aggregates (FRA). Asopposed to the better known external sulfate attack or Delayed Ettringite Formation (DEF), the sulfates inthis context are provided by a gypsum contamination of the aggregates. Mortars made with contami-nated FRA were subjected to different conditions, to assess which parameters had an influence on the sul-fate attack reaction. Their mechanical properties and microstructure are investigated. Results showedthat gypsum content, porosity, temperature and alkalinity influenced the consequences of sulfate attack.However, the gypsum size distribution and cement type did not. [less ▲]

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See detailModelling thermal and humidity transfers within green roof systems: effect of rubber crumbs and volcanic gravel
Kazemi, Mostafa ULiege; Courard, Luc ULiege

in Advances in Building Energy Research (2020)

The use of recycled materials and porous aggregates such as rubber crumbs and volcanic gravel (pozzolana) for the drainage layer can lead to improving thermal behaviour of the green roofs. On the other ... [more ▼]

The use of recycled materials and porous aggregates such as rubber crumbs and volcanic gravel (pozzolana) for the drainage layer can lead to improving thermal behaviour of the green roofs. On the other hand, the thermal performances of green roofs can be affected by the thickness of substrate and drainage layer. Therefore, the main objective of this study was to adapt modelling characteristics for different thicknesses of substrate and drainage layers used under constant and variable temperatures and solar radiation: specific rubber crumbs and volcanic gravel behaviour has been modelled. The simultaneous heat and moisture transfers within the green roof were estimated as well. According to the results, the 9cm substrate was recommended to be used for the green roofs, once the thickness of drainage layer was 4cm. Moreover, the optimum thickness of pozzolana and rubber crumbs as drainage layer was 6cm and 7cm, respectively, once the thickness of the substrate was kept constant (5cm). By increasing the thickness of substrate and drainage layers, the fluctuation of internal ceiling temperature in the green roof models with the presence of humidity decreased, but not as much as that in the green roof models without the presence of humidity. [less ▲]

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See detailThermophysical and mechanical properties of compressed earth blocks containing fibres: By-product of okra plant & polymer waste
Nshimiyimana, Philbert ULiege; Hema, Césaire; Zoungrana, Ousmane ULiege et al

in WIT: Transactions on the Built Environment (2020), 195

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See detailInfluence of temperature on the creep behaviour by macroindentation of Cocos nucifera shells and Canarium schweinfurthii cores (bio-shellnut wastes in Cameroon)
Ganou Koungang, Bernard Morino ULiege; Ndapeu, Dieunedort; Tchuindjang, Jérôme Tchoufack ULiege et al

in Materials Research Express (2020), 7(10), 14

The aim of this study was to show how temperature modifies the mechanical characteristics of the Cocos nucifera (CN) shells and the Canarium schweinfurthii (CS) cores. The test consisted in performing an ... [more ▼]

The aim of this study was to show how temperature modifies the mechanical characteristics of the Cocos nucifera (CN) shells and the Canarium schweinfurthii (CS) cores. The test consisted in performing an instrumented macroindentation on prismatic specimens in an adiabatic chamber; the indentation carried out according to four temperature ranges (30 °C, 50 °C, 70 °C, 90 °C). The Oliver and Pharr method is used for the analysis of mechanical parameters in indentation: reduced Young's modulus, hardness, creep coefficient. These parameters have enabled to estimate indirect characteristics such as toughness and ultimate mechanical stress to be obtained. The creep data are simulated to have the rheological model to these materials by considering the statistical criteria. As a global observation, when the temperature increases, the mechanical parameters decrease; although CN is more sensitive to the temperature gradient than CS, these 2 materials show performances that allow them to be classified as engineering polymer materials according to the Ashby diagram. [less ▲]

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See detailPhysical, Water Diffusion and Micro-Structural Analysis of “Canarium Schweinfurthii Engl”
Ganou Koungang, Bernard Morino ULiege; Ndapeu, Dieunedort; Tchemou, Gilbert et al

in Materials Sciences and Applications (2020), 11(9), 626-643

The purpose of this study is to determine the morphological, microstructural characteristics and water diffusion parameters of the Canarium schweinfurthii (CS) shellnut. This work is part of a vast ... [more ▼]

The purpose of this study is to determine the morphological, microstructural characteristics and water diffusion parameters of the Canarium schweinfurthii (CS) shellnut. This work is part of a vast project to valorize the above-mentioned cores for possible industrial use as charges in composites or abrasives materials. The study was based on the characterization of intrinsic physical characteristics of the coreshells scanning electron microscopic (SEM) observations desorption, adsorption and absorption kinetics. The water diffusion phenomenon was modeled and it appears that the Page model well predicted the kinetic of drying, absorption and adsorption. The effective diffusion coefficient and the energy of activation were calculated at three isothermal temperatures (50˚C, 70˚C and 90˚C). There was a tendency for hysteresis in the sorption-desorption cycles. These results strongly predicted the possibility of using these products as a filler in composites, clay building materials and cement because of their high water diffusion stability on a macroscopic scale. [less ▲]

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See detailUse of municipal solid waste incineration bottom ash for roller compacted concrete
Zhao, Zengfeng ULiege; HYOUMBI TCHUNGOUELIEU, William; Michel, Frédéric ULiege et al

Scientific conference (2020, September)

241 million tons of municipal solid waste (MSW) is generated annually in the European Union (data from 2014), which produce 16 million tons of MSW incineration bottom ash (MSWIBA) per annum. Due to the ... [more ▼]

241 million tons of municipal solid waste (MSW) is generated annually in the European Union (data from 2014), which produce 16 million tons of MSW incineration bottom ash (MSWIBA) per annum. Due to the promotion of waste recycling, the use of MSWIBA as construction materials has gained much attention during the last decade. In this paper, the use of MSWIBA as aggregate for roller compacted concrete has been assessed. [less ▲]

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See detailPhysico-Mechanical and Hygro-Thermal Properties of Compressed Earth Blocks Stabilized with Industrial and Agro By-Product Binders
Nshimiyimana, Philbert ULiege; Messan, Adamah; Courard, Luc ULiege

in Materials (2020), 13

This study investigated the engineering properties of compressed earth blocks (CEBs) stabilized with by-product binders: calcium carbide residue (CCR) and rice husk ash (RHA). The dry mixtures were ... [more ▼]

This study investigated the engineering properties of compressed earth blocks (CEBs) stabilized with by-product binders: calcium carbide residue (CCR) and rice husk ash (RHA). The dry mixtures were prepared using the earthen material and 0–25 wt% CCR, firstly, and 20 wt% CCR partially substituted by the RHA (CCR:RHA in 20:0 - 12:8 ratios), secondly. The appropriate amount of water was thoroughly mixed with the dry mixtures. The moistened mixtures were manually compressed into CEBs, cured, dried, and tested. The stabilization of CEBs with CCR increased the dry compressive strength (CS) from 1.1 MPa with 0% CCR to 4.3 MPa with 10% CCR and above; decreased the bulk density (ρb:1800–1475 kg/m3) and increased the total porosity (TP:35–45%). This resulted in the improvement of the coefficient of structural efficiency (CSE: 610–3050 Pa∙m3/kg). It also improved the thermal efficiency given the decrease of the thermal conductivity (λ: 1.02–0.69 W/m∙K), thermal diffusivity (a: 6.3 × 10−7 to 4.7 × 10−7 m²/s) and thermal penetration depth (δp: 0.13–0.11 m). The RHA further improved the CS up to 7 MPa, reaching the optimum with 16:4 CCR:RHA (ρb: 1575 kg/m3 and TP: 40%). The latter reached higher CSE (4460 Pa∙m3/kg) than cement stabilized CEBs (3540 Pa∙m3/kg). It reached lower λ (0.64 w/m∙K), a (4.1 × 10−7 m²/s) and δp (0.11 m) than cement CEBs (1.01 w/m∙K, 6.8 × 10−7 m²/s, and 0.14 m). Additionally, the stabilization of CEBs with by-products improved the moisture sorption capacity. The improvement of the structural and thermal efficiency of CEBs by the stabilization with by-product binders is beneficial for load-bearing capacity and thermal performances in multi-storey buildings. [less ▲]

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See detailUse of Recycled Fine Aggregates from C&DW for Unbound Road Sub-Base
Courard, Luc ULiege; Rondeux, Mélanie ULiege; Zhao, Zengfeng ULiege et al

in Materials (2020), 13(13), 2994

Fine recycled aggregates are produced in large quantities when crushing Construction and Demolition Waste (C&DW). Even if coarse recycled aggregates are commonly used for road foundations, fine particles ... [more ▼]

Fine recycled aggregates are produced in large quantities when crushing Construction and Demolition Waste (C&DW). Even if coarse recycled aggregates are commonly used for road foundations, fine particles are often rejected as they are considered detrimental for the long-term behaviour of foundations. Physicochemical, mineralogical and mechanical characterizations (through X-ray diffraction, X-ray fluorescence, the chloride and sulphate contents, Los Angeles abrasion, micro-Deval resistance and static plate load tests) were performed on raw and treated fine recycled materials for understanding both the effects of the preparation, the compaction and the freeze–thaw cycles on the properties and the evolution of fine particles. Special attention was provided to the shape analysis of fines by means of image analyser. The results showed that the main characteristic parameters to be considered are the sieving curve and the proportion of grades. The mixes containing the highest quantity of fine particles, specifically lower than 63 µm, usually inducing a higher water demand and a higher capillary rise. This can be explained by specific surface and bluntness parameters which increase with the finer particles, inducing a higher surface roughness and, consequently, a higher potential interaction with water. Compaction did not seem to have a major effect on the production of fines (despite some breakdown occurred during compaction) and on the shape of materials (the bluntness and convexity increased slightly, while the elongation values remained similar after the compaction process). The static plate load tests showed that bearing capacity is slightly lower than the specifications for the road foundation after compaction. However, the studied material could meet the maximum criteria for secondary roads foundation construction on the wear resistance criteria. Recycled aggregates from C&DW without sufficient quality could be blended with other aggregates to enable their usage for upper-level road foundation. [less ▲]

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See detailAn Experimental Study on the Use of Fonio Straw and Shea Butter Residue for Improving the Thermophysical and Mechanical Properties of Compressed Earth Blocks
Mabila, Etienne; Delvoie, Simon ULiege; Toguyeni, David et al

in Journal of Minerals and Materials Characterization and Engineering (2020), 8(2), 107-132

The efficient use of building materials is one of the responses to increasing urbanization and building energy consumption. Soil as a building material has been used for several thousand years due to its ... [more ▼]

The efficient use of building materials is one of the responses to increasing urbanization and building energy consumption. Soil as a building material has been used for several thousand years due to its availability and its usual properties improving and stabilization techniques used. Thus, fonio straws and shea butter residues are incorporated into tow soil matrix. The objective of this study is to develop a construction eco-material by recycling agricultural and biopolymer by-products in compressed earth blocks (CEB) stabilization and analyze these by-products’ influence on CEB usual properties. To do this, compressed stabilized earth blocks (CSEB) composed of clay and varying proportion (3% to 10%) of fonio straw and shea butter residue incorporated were subjected to thermophysical, flexural, compressive, and durability tests. The results obtained show that the addition of fonio straw and shea butter residues as stabilizers improves compressed stabilized earth blocks thermophysical and mechanical performance and durability. Two different clay materials were studied. Indeed, for these CEB incorporating 3% fonio straw and 3% - 10% shea butter residue, the average compressive strength and three-point bending strength values after 28 days old are respectively 3.478 MPa and 1.062 MPa. In terms of CSEB thermal properties, the average thermal conductivity is 0.549 W/m·K with 3% fonio straw and from 0.667 to 0.798 W/m. K is with 3% - 10% shea butter residue and the average thermal diffusivity is 1.665.10-7 m2/s with 3% FF and 2.24.10-7 m2/s with 3.055.10-7 m2/s with 3% - 10% shea butter residue, while the average specific heat mass is between 1.508 and 1.584 kJ/kg·K. In addition, the shea butter residue incorporated at 3% - 10% improves CSEB water repellency, with capillary coefficient values between 31 and 68 [g/m2·s]1/2 and a contact angle between 43.63°C and 86.4°C. Analysis of the results shows that, it is possible to use these CSEB for single-storey housing construction. [less ▲]

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See detailSpecification Guidelines for Surface Preparation of Concrete prior to Repair
Courard, Luc ULiege; Bissonnette, Benoît; Garbacz, Andrzej et al

in Concrete International (2020)

To achieve a durable, repaired concrete structure, the specifier of a repair project should require the use of equipment, techniques, and procedures that are appropriate for the project objectives ... [more ▼]

To achieve a durable, repaired concrete structure, the specifier of a repair project should require the use of equipment, techniques, and procedures that are appropriate for the project objectives, deterioration mechanism(s), environmental conditions, structural circumstances, and other local conditions and limitations that exist for the specific structure or part of the structure. Success will be dependent on determining the cause and extent of concrete distress or deterioration, establishing realistic repair objectives, and developing a repair strategy to address the problem1,2 Ultimately, the project team must achieve: • The required condition of the substrate regarding cleanliness, roughness, cracking, tensile and compressive strength, chlorides and other aggressive agents, depth of carbonation, moisture content, and temperature; • Compatibility of the existing concrete and reinforcement with the repair and protection materials and systems, and compatibility between different repair and protection products, including avoiding the risk of creating conditions which may cause acceleration of corrosion; • The specified characteristics and properties of repair materials and systems and the composite repair system regarding the fulfilment of their purpose to prolong the useful service life of the structure; and • The required repair application conditions like ambient temperature, humidity, wind force, precipitation, and any temporary protection. Concrete surface preparation deals with the various operations needed to fulfill these requirements. This article summarizes the results and outcome of a research project titled “Development of Specifications and Performance Criteria for Surface Preparation Based on Issues Related to Bond Strength.”3 The work was sponsored by the ACI Foundation’s Concrete Research Council, Farmington Hills, MI, and the U.S. Department of the Interior’s Bureau of Reclamation (USBoR), Denver, CO. The research was also supported by Laval University, Quebec City, QC, Canada; the University of Liège, Liège, Belgium; and Warsaw University of Technology, Warsaw, Poland. [less ▲]

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See detailPhysico-chemical and mineralogical characterization of clay materials suitable for production of stabilized compressed earth blocks
Nshimiyimana, Philbert ULiege; Fagel, Nathalie ULiege; Messan, Adamah et al

in Construction and Building Materials (2020), 241

The main objective of this study is to characterize the physico-chemical and mineral properties of clay materials from Burkina Faso to produce stabilized compressed earth blocks (CEBs). The reactivity of ... [more ▼]

The main objective of this study is to characterize the physico-chemical and mineral properties of clay materials from Burkina Faso to produce stabilized compressed earth blocks (CEBs). The reactivity of the clay materials was tested based on the electrical conductivity of solutions and the compressive strength of CEBs stabilized with 0–20 wt% CCR (calcium carbide residue) and cured for 45 days at 40 ± 2 °C. Pabre and Kossodo respectively contain the highest fractions of clay (20–30%) and gravel (40%). Saaba and Pabre contain the highest content of kaolinite (60–70%) and quartz (45–60%) and recorded the highest and lowest reactivity, respectively. The compressive strength of CEBs stabilized with 20% CCR improved tenfold (0.8–8.3 MPa) for Saaba and only 2.6 (2–7.1 MPa) for Pabre. The clay materials in the present study are suitable to produce CCR-stabilized CEBs for load-bearing construction. [less ▲]

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See detailEffects of production and curing conditions on performances of stabilized compressed earth blocks: Kaolinite vs quartz-rich materials
Nshimiyimana, Philbert ULiege; Moussa, Seini Hassan; Messan, Adamah et al

in MRS Advances (2020)

This study investigated the effect of production and curing parameters on the mechanical performance of compressed earth blocks (CEBs) stabilized with 0-20 wt % CCR (calcium carbide residue). Kaolinite (K ... [more ▼]

This study investigated the effect of production and curing parameters on the mechanical performance of compressed earth blocks (CEBs) stabilized with 0-20 wt % CCR (calcium carbide residue). Kaolinite (K) and quartz (Q)-rich earthen materials were mixed with the CCR and used to mould CEBs at optimum moisture content (OMC) and OMC+2 % of the dry mixtures, cured at 20 °C, ambient temperature in the lab (30±5 °C) and 40 °C for 0-90 days. After curing, the reactivity of the materials and compressive strength of dry CEBs were tested. Increasing the moulding moisture from OMC to OMC+2 decreased the compressive strength 0.3 times (4.4 to 3.3 MPa) for the CEBs stabilized with 20 % CCR cured at 30±5 °C for 45 days. Similarly, the compressive strength (4.4 MPa) was reached by CEBs stabilized with 10 and 20 % CCR after 28 and 45 days of curing, respectively. At 40 °C, the compressive strength increased 3.3 times (1.1 to 4.7 MPa with 0 to 20 % CCR) for K-rich and 2.5 times (2 to 7.1 MPa) for Q˗rich materials. At 20 °C, the compressive strength increased only 1.3 times (1.1 to 2.5 MPa) for K˗rich and barely 0.7 times (2 to 3.4 MPa) for Q-rich materials. These suggest that CCR is useful for stabilization and improving the performances of CEBs in hot regions. [less ▲]

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