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Performance of Concrete Containing Partial Granite and Tiling Wastes as Fine Aggregate

Kherraf Leila, Kherraf Sihem, Hebhoub Houria, Belachia Mouloud

Civil and Environmental Engineering Reports

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2023

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Vol. 33, no. 2

85--105

EN

The objective of this paper is to study the properties of different compositions of concrete made by substituting sand made of crushed limestone, which is over-exploited in Algeria, by two types of sands produced by the recycling of double-layer tiling and granite waste, respectively, with different mass percentages of 0, 10, 20 and 30%. The physical, mechanical and some aspects of the durability properties of six concretes were evaluated and compared to those of a reference concrete. The results obtained show that the incorporation of granite sand up to a rate of 20% improves the compressive strength and the resistance to acid CH3COOH. For concretes made with tiling sand, the best compressive strength was observed in concrete with an addition rate of 10%. Furthermore, good tensile strength by splitting is obtained with rates of up to 30% of the two recycled sands.

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Influence of Biomass Ash on the Performance and Durability of Mortar

Ramdane Rihab, Kherraf Leila, Abdelouahed Assia, Belachia Mouloud

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 2

53--71

EN

This work revolves around the study of the partial substitution of cement by biomass ash (residue generated during incineration of wood waste) in mortar. The introduction of wood ash in the cement formulation allows solving some problems related to the lack of construction materials and protecting the environment. To carry out this work we have introduced wood ash as an addition which partially substitutes cement at three different replacement percentages (5%, 10% and 15%). We carried out tests on mortar in the fresh state (consistency, density and occluded air); evaluated its performance in the hardened state (compressive and flexural tensile strength), dimensional stability and its durability (water absorption by immersion and by capillarity as well as resistance to chlorides and acidic environments followed by XRD). Results obtained will be compared with the results of control samples with 0% substitution rate. The results of this valorisation show that the incorporation of 5% of ash fillers in the cement improves mechanical resistance as well as certain durability parameters.

3

The study of the characteristics of sand concrete based on marble waste sand

Bebhalilou Mohamed Ichem, Belachia Mouloud, Houari Hacene, Abdelouahed Assia

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 1

130--144

EN

The present study aims to valorize the waste and in particular the waste from the Fil-fila quarry. The main reason for choosing the waste from this quarry was the need to reduce the impact on the environment (by reducing stockpiling) and the raw material cost (economic reason). This study therefore consists in recovering this type of waste (discarded powder subject to weather changes) as sand in partial replacement of dune sand in the formulation of sand concrete with percentages of 5, 10, 15 and 20 %, by studying the behavior of these concretes in the fresh state (workability, density and occluded air) and the properties in the hardened state (compressive and tensile strength by bending, absorption by immersion, shrinkage and weight loss, chemical effect of HCl and H2SO4 solutions), and subsequently comparing the results obtained with reference samples (0%) based on ordinary sand. Based on the obtained results, it can be concluded that the substitution of ordinary (dune) sand with marble waste sand provides acceptable results from the point of view of workability, strength and durability. These observations are likely to widen the field of applications of these sand concretes based on marble waste.

4

Estimation of the adherence of mortars using ultrasound

Khaldi Nacera, Belachia Mouloud, Benouis Abdelhalim

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 2

185--199

EN

Mortars are subjected to severe external stresses such as freezing, thawing, and drying during their lifetime. These stresses can lead to a loss of adhesion between the support and the mortar. The strength of the substrates with respect to their ability to receive a coating (mortar) is characterized in particular by the value of minimum tear resistance of the surface to be coated. In this work, the use of a non-destructive method which is both fast and easy to implement is employed to evaluate this support-mortar adhesion. The first method is based on the measurement of the velocities of the surface ultrasonic waves and the second by tearing tests using a specific dynamometer. The determination of the adhesion strength concerned two different supports (concrete beam and masonry block) coated with two types of mortar (a prepared cement mortar and a ready-to-use mortar) with two different thicknesses for each mortar (1 and 2 cm, respectively). The results of the two methods are then correlated for an estimation of the adhesion of the mortars.

5

Elaboration of an expert system for sizing, designing and verifying flexible pavements

Bouacha Nadjet, Belachia Mouloud

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 3

94--121

EN

The use of expert systems in the world of civil engineering, and in particular for roads, has become a necessity for the reason of the particularity, complexity, and diversity of the influencing parameters at the level of the design calculation, the latter of which represents the major source of subsequent degradation. This system consists of proposing a tool for helping the user firstly to size the body of the roadway, with several analytical methods and models (Pre-project, Boussinesq, Westgaard, and Burmister), and secondly, to offer different design possibilities (thickness and type of the material) that make up the layers. Lastly, it is to calculate the stresses and strains in order to compare them with admissible limits. The management of a knowledge base of complex natures (words, sentences, numbers, symbols, tables, calculation methods, equations, conditions, etc.) requires an adequate methodology which goes beyond the simple use of the technology but enables you to imagine the process of regrouping this mass of complex data and classifying the data, which can then be integrated into a database or spreadsheets and external programs designed with code compatible with the expert system generator. Our contribution relates initially to the formulation, organization, and preparation of the algorithms, and then the starting of the programs in order to conceive fully executable programs, the latter of which we can call the expert system. The validation of such a system was made as the work progressed, changes were made in the formulation of the rules, and the order and orientation of the data in the knowledge that the advantage of this type of system is the possibility of permanently reinforcing the database with human expertise in the field, or in books, especially so that we can avoid data loss due to illnesses, retirement, etc.

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Contribution to the study of the durability of rubberized concrete in aggressive environments

Kechkar Chiraz, Belachia Mouloud, Cherait Yacine

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 1

111--129

EN

Today, much of the world’s waste, in particular used tires, is accumulating as a potential source of major environmental and economic problems. In order to better preserve the environment, and in the face of changes in the legislation in force, many recovery actions have been carried out especially in the field of building materials. The present research aims to contribute to the study of the mechanical properties and durability of concretes based on rubber aggregates. To achieve this objective, we have contemplated incorporating therein amounts of rubber granules according to different volume substitution percentages being 10%, 17.5%, and 25%. A comparison of the results with a control concrete has been established. The obtained results make it possible to demonstrate that the substitution of a percentage of sand by rubber granules decreases the mechanical strengths and increases the expansion in water. On the other hand, it improves the resistance to attack from H2SO4, Na2SO4, and seawater. The latter is evaluated by the loss and gain in mass as well as the loss in mechanical resistance, especially in the long term (more than 90 days), decreases drying shrinkage, thus decreasing microscopic cracks and providing better durability.

7

Effect of Cockele Shells on Mortars Performance in Extreme Conditions

Abdelouahed Assia, Hebhoub Houria, Kherraf Leila, Belachia Mouloud

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 2

60--73

EN

This paper studies the use of cockle shell as supplementary cementitious materials SCMs as substitute for cement. The cockle shells generally have a high CaO content which can alter the behavior and the properties of mortars and concrete. Cockle shell is used with weight ratios of 5, 10, 15 and 20% to formulate a mortar with cockle shell and a control mortar CM with 0% of cockle shell. The properties in the fresh state, the mechanical strength and the weight loss test as well as the depth of penetration of each mixture were carried out through the conducted experiments. Consistency and density of fresh mortars were determined, the results obtained showed that cockle shell have a significant influence on the properties of mortars in the fresh state. The different results of hardened mortars show that the introduction of cockle shell tends to accelerate the development kinetics of strength at the young age but its ratio cannot be above of 5%. Mortar with 10% presented the lower depth penetration, the loss weight increased proportionally with the increasing of cockle shell amount.