References of "Bissonnette, Benoît"
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See detailConcrete repair bond: evaluation and factors of influence
Bissonnette, Benoît; Courard, Luc ULg; Garbacz, Andrzej et al

in Grantham, Michael; Basheer, Muhammed; Magee, Bryan (Eds.) et al Proceedings of the 5th International Conference on Concrete Repair (2014)

Repair and strengthening of existing concrete structures are among the biggest challenges civil engineers are facing today and will have to face in the years to come. Present concerns of sustainable ... [more ▼]

Repair and strengthening of existing concrete structures are among the biggest challenges civil engineers are facing today and will have to face in the years to come. Present concerns of sustainable development emphasizing repair instead of new construction will only strengthen this trend. Concerted efforts towards improving the durability of concrete repairs are still needed from scientists and engineers. One of the critical aspects of durability of concrete repairs and overlays is lasting and sufficient interfacial bond between repair material and existing concrete substrate. This paper summarizes some of the findings of a collaborative study devoted to the most significant factors influencing bond in repairs (roughness, degree of saturation and carbonation of the substrate) and its field evaluation (type of loading, device misalignment). Based on the test results collected in different test programs, guideline-type recommendations for surface preparation prior to repair were issued. [less ▲]

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See detailEvaluation of the mechanical integrity of a concrete surface by means of combined destructive methods
Courard, Luc ULg; Bissonnette, Benoît; Garbacz, Andrzej et al

in Grantham, Michael; Basheer, Muhammed; Magee, Bryan (Eds.) et al Proceedings of Concrete Solutions (2014)

As a tight bond between the repair and the old concrete is required, the soundness of the prepared surface has to be carefully assessed. This paper presents the results of an investigation intended to ... [more ▼]

As a tight bond between the repair and the old concrete is required, the soundness of the prepared surface has to be carefully assessed. This paper presents the results of an investigation intended to assess and compare quantitatively different test methods, namely the Schmidt rebound hammer, the pull-out test and the pull-off test, to evaluate superficial mechanical integrity of a substrate after concrete removal operations. Although it does not yield a precise evaluation of compressive strength, the Schmidt rebound hammer test is recognized as a useful tool for performing quick surveys to assess concrete uniformity. The pull-off test is very well correlated with the splitting-tensile test, but it is not suited for vertical and overhead surfaces. The Capo pull-out test has limited interest for surface preparation, as it is applicable to flat surfaces only. Conversely, the accelerated pull-out test showed interesting potential as a simple and relatively rapid means for assessing the mechanical integrity of a concrete surface prior to repair for any type of concrete surface. It appears from the results generated in this study that the combination Schmidt hammer / pull-off test could fill the needs for the evaluation of horizontal surfaces after concrete removal, while the combination Schmidt hammer / accelerated pull-out test could be used effectively on vertical and overhead surfaces. [less ▲]

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See detailAdhérence des réparations en béton: évaluation et facteurs d'influence
Bissonnette, Benoït; Courard, Luc ULg; Jolin, Marc et al

in Damidot, Denis (Ed.) Actes de la 15ème édition des journées scientifiques (2014)

La réparation et le renforcement des structures existantes en béton comptent parmi les plus importants défis auxquels les ingénieurs civils sont confrontés aujourd’hui et qu’ils devront relever dans les ... [more ▼]

La réparation et le renforcement des structures existantes en béton comptent parmi les plus importants défis auxquels les ingénieurs civils sont confrontés aujourd’hui et qu’ils devront relever dans les années à venir. Les préoccupations actuelles concernant le développement durable favorisent la réfection au détriment de la construction neuve et ne peuvent que renforcer cette tendance. Des efforts concertés de la part des scientifiques et ingénieurs sont encore nécessaires afin d’améliorer la conception des réparations en béton et d’en assurer la qualité et la fiabilité attendues. L’un des aspects essentiels de la durabilité des réparations en béton et des revêtements ou traitements de surface est la qualité de l’adhérence entre le matériau de réparation et le béton existant. Le présent article résume les principales conclusions de travaux réalisés en collaboration en vue d’identifier les facteurs influençant l’adhérence des réparations (la rugosité, le degré de saturation et la carbonatation du substrat) et l’évaluation de celle-ci en conditions in situ (type de chargement, alignement de l’appareil). Sur la base des résultats recueillis, des recommandations concernant la préparation de la surface avant réparation ont été émises dans un guide du USBR aux États-Unis. [less ▲]

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See detailPatch repair: compatibility issues
Garbacz, Andrzej; Courard, Luc ULg; Bissonnette, Benoît et al

in Grantham, Michael; Basheer, Muhammed; Magee, Bryan (Eds.) et al Proceedings of the 5th International Conference on Concrete Repair (2014)

Repair of any concrete structure results in formation of complex, at least two-component repair systems. Compatibility approach is treated as a basic requirement during selection of repair material ... [more ▼]

Repair of any concrete structure results in formation of complex, at least two-component repair systems. Compatibility approach is treated as a basic requirement during selection of repair material. Recently, the understanding for compatibility requirements in repair systems approach is demonstrated in many papers. The aim of this paper is analyzing the compatibility between repair materials and concrete substrate in the case of patch repair. The compatibility issues were discussed in light of the various requirements which determine the mathematical space of loads, including chemical, mechanical and other physical (mainly thermal) loads. N-dimensional compatibility space is created, taking into account selected patch material control parameters. The requirements for good compatibility between repair material and concrete substrate can be formulated by using mathematical inequalities, where the variables are the material control parameters. The effects of properties of the both repair material and concrete substrate were analyzed using computer system ANCOMP developed at Warsaw University of Technology. Usability of this approach was demonstrated using selected case study as an example. [less ▲]

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See detailEffect of misalignment on pull-off test results: numerical and experimental assessments
Courard, Luc ULg; Bissonnette, Benoît; Garbacz, Andrzej et al

in ACI Materials Journal (2014), 111(2), 153-162

The successful application of a concrete repair system is often evaluated through pull-off testing. For such in-situ quality control (QC) testing, the inherent risk of misalignment might affect the ... [more ▼]

The successful application of a concrete repair system is often evaluated through pull-off testing. For such in-situ quality control (QC) testing, the inherent risk of misalignment might affect the recorded value and eventually make a difference in the acceptance of the work. So far, the issue of eccentricity in pull-off testing has been ignored in field practice, because it is seen as an academic issue. This paper presents the results of a project intended to quantify the effect of misalignment on pull-off tensile strength evaluation and provide a basis for improving QC specifications if necessary. The test program consisted first in an analytical evaluation of the problem through 2-D FEM simulations and, in a second phase, in laboratory experiments in which the test variables were the misalignment angle (0°, 2° and 4°) and the coring depth (15 mm [1.18 in.], 30 mm [2.36 in.]). It was found that calculations provide a conservative but realistic lower bound limit for evaluation the influence of misalignment upon pull-off test results: a 2° misalignment can be expect to yield a pull-off strength reduction of 7 to 9 % respectively for 15-mm [1.18-in.] and 30-mm [2.36-in.] coring depths, and the corresponding decrease resulting from a 4° misalignment reach between 13 and 16%; From a practical standpoint, the results generated in this study indicate that when specifying a pull-off strength limit in the field, the value should be increased (probable order of magnitude: 15%) to take into account the potential reduction due to testing misalignment. [less ▲]

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See detailDurabilité (s) des matériaux de construction : un challenge pour l’ingénieur
Courard, Luc ULg; Bissonnette, Benoît

Conference (2013, May 10)

Le choix des matériaux utilisés dans la construction repose sur des critères techniques identifiables et quantifiables tels la résistance mécanique, le comportement chimique ou le transfert de chaleur ... [more ▼]

Le choix des matériaux utilisés dans la construction repose sur des critères techniques identifiables et quantifiables tels la résistance mécanique, le comportement chimique ou le transfert de chaleur, paramètres qui permettent non seulement de satisfaire les exigences opérationnelles de l'ouvrage, mais aussi d'en garantir la durabilité et la durée de vie utile attendues. Quoi qu'il en soit, ces critères ne sont aujourd’hui plus suffisants: énergie grise, analyse de cycle de vie, incidence sur l’environnement, qualité environnementale des constructions, etc. sont de nouveaux facteurs qui interviennent dans le caractère « durable » des constructions. L’ingénieur se doit désormais d'intégrer ces considérations dans le dimensionnement et la réalisation des ouvrages, ce qui constitue un réel challenge pour l’avenir. [less ▲]

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See detailA surface engineering approach applicable to concrete repair engineering
Garbacz, Andrzej; Courard, Luc ULg; Bissonnette, Benoît

in Bulletin of the Polish Academy of Sciences. Technical Sciences (2013), 61(1), 73-84

The objective of the paper is to analyze the effect of surface roughness and superficial microcracking upon dhesion of repair systems using concrete surface engineering approach. The results presented in ... [more ▼]

The objective of the paper is to analyze the effect of surface roughness and superficial microcracking upon dhesion of repair systems using concrete surface engineering approach. The results presented in this paper have been obtained within the framework of research projetcs performed to develop a better understanding of factors affecting the adhesion of repair materials through a surface engineering approach. Based on the results of investigations, the authors showed that the durability and quality of concrete repairs depend to a large degree on the characteristics of the substrate. Mechanical preparation and profiling of the concrete surface to be repaired has to be balanced with potential co-lateral effects such as superficial cracking, too often induced as a result of inappropriate concrete removal method selection, and the loss of benefits due to better mechanical anchorage. The results obtained confirm also that Concrete Surface Engineering, as a scientific concept, will definitely contribute to shed more light on how to optimize repair bond, taking into account interactions between materials at different observation scales. [less ▲]

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See detailRecommendations for the repair, the lining or the strengthening of concrete slabs or pavements with bonded cement-based material overlays
Courard, Luc ULg; Bissonnette, Benoît; Beushausen, Hans et al

in Materials and Structures (2013), 46

The recommendations presented in this publication are inspired by the State of the Art Report edited by the RILEM technical committee TC 193 RLS Bonded cement-based material overlays for the repair, the ... [more ▼]

The recommendations presented in this publication are inspired by the State of the Art Report edited by the RILEM technical committee TC 193 RLS Bonded cement-based material overlays for the repair, the lining or the strengthening of slabs and pavements. The objective is to lay out all the practical aspects to be considered in the design of concrete overlays: bonded concrete overlay process, assessment of the existing structure, surface preparation, overlay materials, design methods, construction procedure and quality control/assurance (QC/QA) system, and maintenance. [less ▲]

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See detailTopography evaluation methods for concrete substrates: parametric study
Courard, Luc ULg; Garbacz, Andrzej; Bissonnette, Benoît

in Alexander, Mark (Ed.) Concrete Repair, Rehabilitation and Retrofitting III (2012)

Research projects performed at the University of Liege, Laval University and the Warsaw University of Technology have pointed out the importance of taking care about the surface roughness of concrete ... [more ▼]

Research projects performed at the University of Liege, Laval University and the Warsaw University of Technology have pointed out the importance of taking care about the surface roughness of concrete substrate with regards to the adhesion of repair materials. This paper wants to make a State-of-Art on this specific problem: surfometry methods, interface analysis, adhesion measurements, …etc are presented, interpreted and compared. Surfology, which is a more wide concept, contributes to understand what will make the contact effective or not, and allow interactions of variable intensities between the materials. Different scales of observation – micro to macro - are needed to exactly represent what happens when materials are put into contact. [less ▲]

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See detailComparison of Destructive Methods to Appraise the Mechanical Integrity of a Concrete Surface
Courard, Luc ULg; Bissonnette, Benoît; Vaysburd, Alex et al

in Concrete Repair Bulletin (2012), 25(4), 22-30

Depending on the technique being used, the concrete removal operation prior to repair can be harmful to the residual concrete skin left on the structure. Whenever a tight bond between the repair and the ... [more ▼]

Depending on the technique being used, the concrete removal operation prior to repair can be harmful to the residual concrete skin left on the structure. Whenever a tight bond between the repair and the old concrete is required, the soundness of the prepared surface should thus be assessed. Although this is widely recognized, there is no standard method intended to characterize the integrity of a concrete substrate after concrete removal. This paper presents the results of an investigation intended to assess and compare quantitatively different test methods, namely the Schmidt rebound hammer, the pull-out test and the pull-off test, to evaluate superficial mechanical integrity of a substrate after concrete removal operations. Although it does not yield a precise evaluation of compressive strength, the Schmidt rebound hammer test is recognized as a useful tool for performing quick surveys to assess concrete uniformity. The pull-off test is very well correlated with the splitting-tensile test, but it is not suited for vertical and overhead surfaces. The Capo pull-out test has limited interest for surface preparation, as it is applicable to flat surfaces only. Conversely, the accelerated pull-out test showed interesting potential as a simple and relatively rapid means for assessing the mechanical integrity of a concrete surface prior to repair for any type of concrete surface. More work is definitely required to refine the procedures and develop performance criteria. Nevertheless, it appears from the results generated in this study that the combination Schmidt hammer / pull-off test could fill the needs for the evaluation of horizontal surfaces after concrete removal, while the combination Schmidt hammer / accelerated pull-out test could be used effectively on vertical and overhead surfaces. [less ▲]

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See detailQuality assurance in repairing industrial floors: parameters and recommendations
Courard, Luc ULg; Bissonnette, Benoît

in Zajc, A.; Sustercic, J. (Eds.) Moznot Pocenitive Izvajanja Betonarskih Del (2011)

Since concrete has been used for more than a century, many structures need repair in different degrees and others need strengthening to withstand higher loads. Moreover, the number of new concrete ... [more ▼]

Since concrete has been used for more than a century, many structures need repair in different degrees and others need strengthening to withstand higher loads. Moreover, the number of new concrete structures is constantly increasing, and therefore repair or retrofitting requirements increase. Present concerns of sustainable development emphasizing repair or strengthening instead of new construction, acts as incentive to this trend. The bonded overlay technique is particularly suitable in the case of structures with large areas like industrial floors. This paper has the ambition to present reliable design methodology for the practitioner. Surface preparation, overlay design and material selection, application process and QC/QA are discussed and guidelines are proposed in order to enhance quality of repair operations. [less ▲]

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See detailBonded cement-based material overlays for the repair, the lining or the strengthening of slabs and pavements
Bissonnette, Benoît; Courard, Luc ULg; Fowler, David et al

Book published by Springer (2011)

1.0 INTRODUCTION 2.0 OVERLAY DESIGN PROCESS 3.0 CONDITION EVALUATION OF THE EXISTING STRUCTURE PRIOR TO OVERLAY 4.0 BOND 5.0 STRUCTURAL BEHAVIOUR 6.0 DEBONDING 7.0 DESIGN 8.0 PRACTICE AND QUALITY ... [more ▼]

1.0 INTRODUCTION 2.0 OVERLAY DESIGN PROCESS 3.0 CONDITION EVALUATION OF THE EXISTING STRUCTURE PRIOR TO OVERLAY 4.0 BOND 5.0 STRUCTURAL BEHAVIOUR 6.0 DEBONDING 7.0 DESIGN 8.0 PRACTICE AND QUALITY ASSURANCE 9.0 MAINTENANCE AND REPAIR OF OVERLAYS 10.0 CONCLUSION [less ▲]

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See detailCondition evaluation of the existing structure prior to overlay (chapter 3)
Courard, Luc ULg; Trevino, Manuel; Bissonnette, Benoît

in Bissonnette, Benoît; Courard, Luc; Fowler, David (Eds.) et al Bonded cement-based material overlays for the repair, the lining or the strengthening of slabs and pavements (2011)

The knowledge and analysis of the causes of degradations is the first step in repairing existing concrete structures. The assessment is performed by using destructive and non destructive methods. These ... [more ▼]

The knowledge and analysis of the causes of degradations is the first step in repairing existing concrete structures. The assessment is performed by using destructive and non destructive methods. These allow detecting modification of physical, chemical and/or mechanical properties of concrete: cracking, deformation, spalling, carbonation, etc., are various causes of distress, with potential irreversible consequences on concrete structure behaviour. A description of specific methods for pavements and structural slabs is proposed; it is usually recommended to combine complementary methods for efficient diagnosis. This chapter wants to offer an overview of techniques and references that could help the user in selecting the most appropriate investigation program. [less ▲]

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See detailRepairing Concrete Industrial Floors with Bonded Cement-based Material Overlays: some recommendations
Courard, Luc ULg; Bissonnette, Benoît; Vaysburd, Alex

in Littmann, Klaus (Ed.) Industrial Floors 2010 (2010)

Since concrete has been used for more than a century, many structures need repair in different degrees and others need strengthening to withstand higher loads. Moreover, the number of new concrete ... [more ▼]

Since concrete has been used for more than a century, many structures need repair in different degrees and others need strengthening to withstand higher loads. Moreover, the number of new concrete structures is constantly increasing, and therefore repair or retrofitting requirements increase. Present concerns of sustainable development emphasizing repair or strengthening instead of new construction, acts as incentive to this trend. The bonded overlay technique is particularly suitable in the case of structures with large areas like industrial floors. This paper has the ambition to present reliable design methodology for the practitioner. Surface preparation, overlay design and material selection, application process and QC/QA are discussed and guidelines are proposed in order to enhance quality of repair operations. [less ▲]

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See detailCombination of mechanical and optical profilometry techniques for concrete surface roughness characterization
Perez, Fabien; Bissonnette, Benoît; Courard, Luc ULg

in Magazine of Concrete Research (2009), 61(6)

Achieving durable bond between new and old concrete still represents a challenge in concrete repair technology. It has been the subject of a number of investigations, but in most cases, only adhesion ... [more ▼]

Achieving durable bond between new and old concrete still represents a challenge in concrete repair technology. It has been the subject of a number of investigations, but in most cases, only adhesion strength was addressed. To better understand bond mechanisms, in particular those related to surface roughness, two complementary surface characterisation techniques were implemented, providing a multiscale roughness characterisation by means of specific filtering calculations: mechanical profilometry for low-scale roughness and optical profilometry for the upscale roughness. Using these complementary approaches, different types of concrete surface preparation were characterised. The resulting description highlights the complexity of concrete surface topography. Moreover, it shows that the type of surface preparation essentially affects the meso- and macro-roughness levels, microroughness being practically insensitive. Such results will be useful for better understanding the interlocking potential and bond performance of concrete repairs. [less ▲]

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See detailCorrelation between the roughness of the substrate surface and the debonding risk
Perez, Fabien; Morency, Maxim; Bissonnette, Benoît et al

in Alexander, M. G.; Beushausen, H.-D.; Dehn, F. (Eds.) et al Concrete Repair, Rehabilitation and Retrofitting II (2009)

This paper presents the influence of substrate surface preparation on the adhesion strength of repaired beams system. Bond between new and old concrete has been the subject of a number of investigations ... [more ▼]

This paper presents the influence of substrate surface preparation on the adhesion strength of repaired beams system. Bond between new and old concrete has been the subject of a number of investigations, but in most cases, only adhesion strength was addressed. This parameter was used to estimate the durability and/or the debonding risk for repaired structure and it’s a generally accepted auditing standards. Usually, surface preparation of the substrate concrete is considered essential to achieve a durable repair because of its influence on the bond strength. To better understand debonding mechanism, in particular these related to surface preparation, roughness parameters were calculated to quantify the influence of surface preparation on the structural behaviour. Using this approach, repair beams prepared by way of four (4) concrete surface preparations were characterized. Results obtained show that repaired beams presenting a substrate with a rough surface permit to achieve a monolithic behaviour of the repaired system. Opposite structural behaviour, with large debonding, was recorded for those having smooth surface. However, all surface preparations used have promoted the same bond strength regardless the roughness of the substrate. The resulting analysis highlights the relation between roughness parameter αrough and the debonding mechanism of repaired beams. Such results will be useful to better predict the performance of concrete repairs. [less ▲]

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See detailCompatibility performance as a fundamental requirement for the repair of concrete structures with Self-Compacting Repair Mortars
Courard, Luc ULg; Bissonnette, Benoît

in De Schutter, Geert; Boel, V. (Eds.) Self Compacting Concrete SCC2007 (2007, September)

Durable adhesion of repair material on concrete substrate requires compatibility between the materials to be bonded. There are four main compatibility components to be addressed in any concrete repair ... [more ▼]

Durable adhesion of repair material on concrete substrate requires compatibility between the materials to be bonded. There are four main compatibility components to be addressed in any concrete repair scenario: dimensional, permeability, chemical and electrochemical compatibility. Among those, dimensional compatibility is often prevalent: while a cement-base repair material inevitably undergoes shrinkage, the substrate opposes to its free movement, a situation that can lead to cracking and, subsequently, promote debonding. Besides, an essential requirement for bond development is the creation of the interface itself: the intimate contact between the repair system and concrete substrate is required in order to maximize adhesion. Adequate compaction of the new layer is consequently one of the main parameters that will govern the quality of the bond: sufficient vibration or specific rheological properties for the repair material are needed. Self-Compacting Repair Mortar (SCRM) can be advantageously used in many repair situations. Limestone fillers seem to offer interesting advantages as addition to these repair materials as they increase the workability of the final product. Several materials have been tested and characterised by means of a physical, chemical and mechanical characterization test program: specific attention has been given to water demand and superplasticizer efficiency. [less ▲]

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See detailConcrete removal techniques: influence on residual cracking and bond strength
Bissonnette, Benoit; Courard, Luc ULg; Vaysburd, Alex et al

in Concrete International (2006), 28(12), 49-55

The aim of concrete surface preparation prior to repair is to obtain a surface with properties close to that of the bulk concrete. In this paper, the results of an investigation intended to evaluate the ... [more ▼]

The aim of concrete surface preparation prior to repair is to obtain a surface with properties close to that of the bulk concrete. In this paper, the results of an investigation intended to evaluate the mechanical degradation induced by different surface preparation techniques are presented. Optical microscope observations clearly show that more cracking is induced with jack-hammers than with the other investigated techniques and that the cracking density increases with the hammer weight. While more information is needed to evaluate quantitatively the effects of concrete removal operations, it appears from the reported results that techniques such as sandblasting, scarifying and water jetting are preferable, as they clearly leave much less defects in the substrate. [less ▲]

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See detailTwo different techniques for the evaluation of concrete surface roughness
Courard, Luc ULg; Perez, Fabien; Bissonnette, Benoît et al

in Beushausen, H.; Dehn, F.; Alexander, M. G. (Eds.) Concrete Repair, Rehabilitation and Retrofitting (2006)

The study of adhesion of repair materials on concrete structures implies a good knowledge of the influence of concrete surface treatment. The effects of surface preparation technique is rarely clearly ... [more ▼]

The study of adhesion of repair materials on concrete structures implies a good knowledge of the influence of concrete surface treatment. The effects of surface preparation technique is rarely clearly described and parameterised: it is consequently difficult to point out the real influence of roughness on adhesion results. A first step was made by using mechanical profilometry to differentiate concrete surfaces prepared by shot blasting, sand blasting and hand or mechanical milling. This technique is very accurate for investigations in laboratory, on a limited surface area. If Quality Control is requested or if it is impossible to core samples from the site, other procedures should be followed. That the reason why opto-morphometry analysis has been developed, in order to analyse larger surfaces. The comparison of the two techniques shows clearly the advan-tages of each one and the precision that can be achieved. [less ▲]

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See detailEffect of surface preparation techniques on the cohesion of superficial concrete: comparison between jack-hammering and water-jetting
Courard, Luc ULg; Bissonnette, Benoît; Belair, Normand

in Beushausen, H.; Dehn, F.; Alexander, M. G. (Eds.) Concrete Repair, Rehabilitation and Retrofitting (2006)

The aim of concrete surface preparation is to obtain a surface with properties similar to those of the bulk concrete. Superficial concrete must be sound, dry, cohesive and contaminant-free. Particularly ... [more ▼]

The aim of concrete surface preparation is to obtain a surface with properties similar to those of the bulk concrete. Superficial concrete must be sound, dry, cohesive and contaminant-free. Particularly, the preparation must be performed in such a way that sound and homogeneous concrete is reached. The most widespread surface preparation techniques are sandblasting, jack-hammering, milling and other water hydro-jetting. Evaluation of the effect of surface preparation is often based upon surface roughness or specific sur-face. It is necessary however to investigate further within the first few centimetres from the surface to verify the concrete homogeneity and soundness. Pull-off test is a destructive method that can be useful for such evaluation, but it only gives an indication; the observation of the failure mode is more instructive. This paper summarizes the results of a microscopy investigation performed to quantify the number and length of cracks. The analysis leads to the comparison of jack-hammering and water-jetting techniques in terms of their poten-tial effect on superficial cohesion of concrete. [less ▲]

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