Publications Internationales
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Item Recycling dam sediments for the elaboration of stabilized blocks(Scientific.net, 2020) Gueffaf, N.; Rabehi, B.; Boumchedda, K.Through this work we propose one of the solutions that allow us to recycle dam sediments as a potential raw material for the development of stabilized soil blocks. For the stabilization of the prepared samples, different percentages of cement and lime were chosen respectively (0, 6, 8, 10 and 15%), (0, 5, 8 and 10%). Different compaction pressures 2, 5 and 7MPa are used. The tests carried out showed very interesting results on the mechanical strength for specimens stabilized with cement up to 8.32MPa for 15% and 5.67MPa for 10% of lime at 7MPa compaction. The obtained water absorption coefficient is about 2.6 for 15% cement and 4.04% for 10% lime; however a thermal conductivity of specimens with cement and lime is about 1.06 and 0.731W/m.k, respectivelyItem Recycling of brick and demolition concrete aggregates wastes in the self compacting concrete(2017) Ghernouti, Y.; Rabehi, B.; Ziani, Nesrine; Tamazirt, S.Item Comparative behavior under compression of concrete columns repaired by fiber reinforced polymer (FRP) jacketing and ultra high-performance fiber reinforced concrete (UHPFRC)(Taylor & Francis, 2014) Rabehi, B.; Ghernouti, Y.; Li, Alex; Boumchedda, K.Item Fresh and hardened properties of self-compacting concrete containing plastic bag waste fibers (WFSCC)(Elsevier Ltd, 2015) Ghernouti, Y.; Rabehi, B.; Bouziani, T.; Ghezraoui, H.; Makhloufi, A.This paper presents the fresh and hardened properties of self-compacting concrete (SCC) containing plastic bag waste fibers (PBWF). Fibers were prepared by recycling waste material such as, plastic bag. Fourteen mixtures of SCC with 0.40 of water/cement ratio were studied, twelve SCC mixtures with plastic bag waste fiber (WFSCC) by varying the length of fibers (2, 4 and 6 cm) with different levels of incorporation (1, 3, 5 and 7 kg/m3) and two other mixtures, one with 1 kg/m3 of polypropylene fibers (PFSCC) and another without fiber as reference (RSCC). Slump flow, L-box, and sieve stability were performed to assess the fresh properties of the prepared mixtures. Compressive strength, splitting tensile strength and flexural strength of the concrete were determined for the hardened properties Test results show that mixtures based on PBWF with a length of 2 cm, met the criteria of self-compactability (evaluated by slump flow diameter, L-box and sieve stability test) regardless of the fibers content. The obtained results are very interesting, suggesting a possible use of PBWF for structural reinforcement of SCC, the presence of this fibers in concrete delaying the location of microcracks. Although, the incorporation of PBWF has not a significant effect on the compressive and flexural strengths, it has a important effect on the split tensile strength value at 28 days. The improvement varies from 4% to 74%, it depends on the amount of fibers, and it is not affected by the length of PBWFItem Study of calcined halloysite clay as pozzolanic material and its potential use in mortars(2012) Rabehi, B.; Boumchedda, K.; Ghernouti, Y.In this research, we will try to understand the mechanisms involved in the introduction of calcined clays in substitution for a portion of cement in the manufacture of mortars. This experimental work focuses on the recovery of a clay type haloysite quality three, from eastern Algeria. This clay comes from a region called Djbel Debbagh hence its name (DD3). The main objective of this study is to see the influence of the activated clay by calcination with different percentages of 5, 10, 15 and 20% in substitution of cement, on the physical-mechanical properties and behaviour of mortars towards chemical attacks. The study of pozzolanic activity allows to optimize a calcinations temperature of about 750°C, the study of its mechanical performance has shown an improvement of strength. Finaly the results of the durability test showed a good performance in different environmentsItem Strength and durability of mortar made with plastics bag waste (MPBW)(Springer, 2012) Ghernouti, Y.; Rabehi, B.The aim of this study is to explore the possibility of re-cycling a waste material that is now produced in large quantities, while achieving an improvement of the mechanical properties and durability of the mortar. This study examines the mechanical properties and the durability parameters of mortars incorporating plastics bag wastes (PBW) as fine aggregate by substitution of a variable percentage of sand (10, 20, 30 and 40 %). The influence of the PBW on the, compressive and flexural strength, drying shrinkage, fire resistance, sulfuric acid attack and chloride diffusion coefficient of the different mortars, has been investigated and analyzed in comparison to the control mortar. The results showed that the use of PBW enabled to reduce by 18–23 % the compressive strength of mortars containing 10 and 20 % of waste respectively, which remains always close to the reference mortar (made without waste). The replacement of sand by PBW in mortar slows down the penetration of chloride ions, improves the behavior of mortars in acidic medium and improves the sensitivity to cracking. The results of this investigation consolidate the idea of the use of PBW in the field of constructionItem Strength and compressive behaviour of ultra high-performance fibre-reinforced concrete (UHPFRC) incorporating algerian calcined clays as pozzolanic materials and silica fume(Taylor & Francis, 2013) Rabehi, B.; Ghernouti, Y.; Boumchedda, K.This paper presents results of an experimental study which investigates the effect of four pozzolan additions made from various by-product materials on physical and mechanical properties of ultra-high performance fibre-reinforced concrete (UHPFRC) compared with the silica fume (SF): waste bricks (WB) and three types of metakaolin (MK) as calcined clays at 750 °C: calcined clay of Djbel Debbagh quality 3 (DD), calcined sludge incineration at the manufacture of paper (PS) and calcined silt of dams (SD) having median particle sizes less than 45 μm are used as addition. For each addition, five percentages of steel fibres (1, 1.5, 2, 2.5 and 3%) were used to improve the performance of concrete. The results suggest that the use of WB, PS and SD has no significant effect on the compressive strength as compared with SF concretes. Calcined clay DD can be used as pozzolanic materials in making UHPFRC. This MK competes with the SF, after 28 days of curing, the concrete containing 25% of DD and 2.5% steel fibre presents a compressive strength of 179 MPa compared with the concrete containing 25% of SF and 2.5% steel fibre, which presents strength of 183 MPaItem FRP-confined short concrete columns under compressive loading : experimental and modeling investigation(Sage, 2011) Ghernouti, Y.; Rabehi, B.This study introduces the results of an experimental investigation on the behavior of the circular columns of concrete under a load of axial compression, confined by an envelope of composite materials (carbon fiber and glass fiber). The composite used is a FRP glued in surface with epoxy resin. The specific objectives of this study are: verifying the applicability of this method of reinforcement of the columns to improve the behavior of concrete from the point of view strength and ductility, seeing the influence of composite materials type used, and confronting the experimental results acquired with different models developed on one hand and on the other hand with empirical formulas developed by other researches. Two models were developed to represent the structural behavior of the tested samples based on the calibration of the experimental results and criterion of Mohr—Coulomb failure. The validity of the results acquired numerically is based on a comparison with experimental results as well as with empirical formulas developedItem Effectiveness of repair on damaged concrete columns by using fiber-reinforced polymer composite and increasing concrete section(Sage, 2012) Ghernouti, Y.; Li, Alex; Rabehi, B.This research is a contribution to work on strengthening and repair of reinforced concrete structures, it presents a comparative study between two methods of repairing damaged concrete with an experimental investigation on the behavior of specimens initially pre-damaged up to intense cracking, repaired by increased concrete section and by bonding a carbon fiber reinforced polymer. In our study, the concrete columns with square sections of (15 × 15) cm2 and a height of 30 cm are tested under uniaxial compression loading up the damage, these columns have been repaired, using both methods, they are tested again and their behavior has been studied. Based on the criterion of Mohr–Coulomb failure, a model was developed for each method to validate the different results obtained experimentally. The experimental results show that the method to repair damaged concrete by carbon fiber reinforced polymer has a good substrate adhesion, which offered a great improvement in strength and ductility compared to the method by increased concrete section. The experimental results have been compared with the theoretical models, a good correlation was obtainedItem Effect of the heat curing on strength development of self-compacting mortars containing calcined silt of dams and ground brick waste(2013) Safi, Brahim; Ghernouti, Y.; Rabehi, B.; Aboutaleb, DjamilaThe strength development of self-compacting mortars (SCM) containing calcined silt (CS) and ground brick waste (GWB) was investigated. The variables are the nature of addition (CS and GWB) in the binder and the heat curing at different temperatures (20 ºC and 60 ºC) at 7 and 14 days of curing. Two temperatures 20 and 60 ºC were applied to samples with intermediate levels (depending on the drying method applied to precast) for 18 hours in total. In this study, a Portland cement (CEMII), Calcined silt (750 ºC for 5 hours), ground waste brick, were used in the binders of SCM. The results show that the compressive strength to 14 days of mortars, increases with annealing (60 ºC) compared to that measured at 20 ºC. Also, values of compressive strength of mortars at 14 days that are close to those obtained without 28 days curing treatment. Indeed, a strength gain of about 20.5% and 27.3% was obtained respectively for the SCM with GWB and the SCM with CS. However, a small change in mass recorded for both types of mortars
