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Behavior immersion of phosphogypsum  crushing sand based bricks
 

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    Behavior immersion of phosphogypsum  crushing sand based bricks Behavior immersion of phosphogypsum crushing sand based bricks Document Transcript

    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME96BEHAVIOR IMMERSION OF PHOSPHOGYPSUM- CRUSHING SANDBASED BRICKSLamia Bouchhima(1), Mohamed Jamel Rouis (2), Mohamed Choura (3)Unit of research environmental geotechnique and civil materials, Institute of the engineers ofSfax, TunisiaAffiliation and address: Institute of the engineers of Sfax, road Sokra, Km3.5, B.P1173-3038Sfax, TunisiaABSTRACTA feasibility study was undertaken on the production of crushing sand-naturalhydraulic lime-cement-phosphogypsum (CS-NHL-C-PG) full bricks to build houseseconomically by utilizing industrial wastes. All full bricks were made on a bench model,semiautomatic press having a capacity of 25 tons, as shown in appendix, to produce bricks of51×95×203 mm in size under a static compaction of 20MPa.The compressive strength, flexural strength water absorption and density of these bricks areinvestigated. It is observed that these bricks have sufficient strength for their use in low costhousing development. Tests were also conducted to study behavior immersion ofphosphogypsum- crushing sand based bricks. The results suggest that these bricks havesufficient behavior immersion.Keywords: Phosphogypsum; crushing sand; strength; immersion1. INTRODUCTIONThere is a general exodus of rural population to the cities with the rapid industrializationin developing countries. The infrastructure to support these cities, such as buildings forhousing and industry, mass transit for moving people and goods, and facilities for handlingwater and sewage will require large amounts of construction materials. Enhancedconstruction activities, shortage of conventional building materials and abundantly availableindustrial wastes have promoted the development of new building materials.INTERNATIONAL JOURNAL OF ADVANCED RESEARCH INENGINEERING AND TECHNOLOGY (IJARET)ISSN 0976 - 6480 (Print)ISSN 0976 - 6499 (Online)Volume 4, Issue 4, May – June 2013, pp. 96-106© IAEME: www.iaeme.com/ijaret.aspJournal Impact Factor (2013): 5.8376 (Calculated by GISI)www.jifactor.comIJARET© I A E M E
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME97Phosphogypsum is an important by-product of phosphoric acid fertilizer industry. Itconsists of CaSO .2H O 4 2 and contains some impurities such as phosphate, fluoride,organic matter and alkalies. In Tunisia, for several years, a set of phosphoric acid productionfactories have produced PG in large great quantities (approximately 10 million tons per year[1]. Currently, the PG is stored into piles in the vicinity of the factory, by dry or wet process.The storage of PG causes the pollution of the water table and the soils by acid and heavymetals infiltrations.Its valorization leads to environmental protection and to minimization of the storagecosts. Several researchers had studied the use of PG in various fields. The PG was treated tobe used in the plaster manufacture. It has been found that the PG is suitable for making goodquality plaster showing similar proprieties to natural gypsum plaster [2-4]. This field isadvantageous for the countries which do not have natural quarries such as Japan and India.The PG has been sought also to be used in agriculture [5]. It is as effective as the crushednatural gypsum. However, the quantities used are limited and moreover the health standardsbecame increasingly restrictive. But the most interesting use of the PG is for the cementmanufacturing: either by natural gypsum substitution (about 5%), which will play the role ofa set retarder [6-7], or to reduce the clinkerization temperature [8]. The PG was also used insoil stabilization [9]. Finally phosphogypsum PG has been studied to be used in hollowblocks [10] and light brick [11].In Tunisia, the PG was studied to be used in similar fields. The most successfulapplication so far is in the manufacture of cement; by substitution of the gypsum. Theobtained product is known under the name of cement ultimo. It showed good performancesbut the used quantity is low [12-13]. Moussa et al [14] had studied the possibility of the useof the PG in the embankments. The PG is studied in order to use it like a fill. This studyshowed a behavior to the compaction not similar to that of a soil. Furthermore, the fillshowed also a continuous settlement because of the PG solubility. Moreover, Kuryatnyk andAngulski- Ambroise- Pera [15] have employed the Gabes and Skhira PG to be used as ahydraulic binder. But formation of ettringite led to cracking and strength loss. Finally, Sfar[16] has explored the PG for a road use. The study proposed the following formulation:46.5% of PG, 46.5% of sand and 7% of cement. But this study was conducted in the Tunisiansouth region, where the rainfall is low.In this paper, at first, compressive strength, flexural strength water absorption anddensity of phosphogypsum- crushing sand-lime-cement bricks grade NW are investigated.The second part deals with the Behavior immersion of phosphogypsum- crushing sand basedbricks2. EXPERIMENTAL PROGRAM2.1.Chemical compositionThe chemical analyses, considered most relevant to the prospect use in commercialbrick making, were undertaken on the PG. The results of these analyses are presented inTable 1. The PG is primarily (about 77%) made up of calcium sulfate (CaSO4). Theremaining components are present at low percentage. It should be noted that the pH of PGsamples has been found to be around 2.9, indicating a high acidity of the PG.
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME98Table1. Chemical composition of phosphogypsumElements (%)CaO SO3 P2O5 F SiO2 Fe2O3 Al2O3 MgOIgnitionloss at1000°C32.8 44.4 1.69 0.55 1.37 0.03 0.11 0.007 22.32.2. Grain densityThe real densities of the grains were determined by the pycnometer method, by usingwater saturated with gypsum. The studied PG presents a density of about 2300 kg/m3. Thereal densities of the grains were determined by the pycnometer method. The studied crushingsand presented a density of about 2740 kg/m3 kg/m3. This value is higher than the one forphosphogypsum.2.3. Application of Phosphogypsum in the solid brick2.3.1. Mix proportionIn the present study, a low slump mix was used to limit the shrinkage. The water contents ofPhosphogypsum-crushing sand-lime mixtures were fixed respectively to 4 %. Bricksproduced with more than 5 % showed cracks after fabrication due to excessive water.The mix proportions of phosphogypsum, crushing sand (CS), lime and cement (cement HRS42.5) for bricks are given in table 2. The mix proportions are given in terms of dry weights ofthe ingredients.Table 2 Mix proportions of CS-NHL-C-PG full bricksMix désignationConstituant materials (Weight %)Phosphogypsum Sand (CS) Cement LimeP-1 60 33 5 2P-2 60 30.5 7.5 2P-3 60 28 10 2P-4 70 23 5 2P-5 70 20.5 7.5 2P-6 70 18 10 2P-7 80 13 5 2P-8 80 10.5 7.5 2P-9 80 8 10 22.3.2. Manufacturing process2.3.2.1 Mixing of raw materialsA mixer is used for mixing materials. The dry phosphogypsum was sieved through 1mm sieve. The weighed quantity of phosphogypsum, crushing sand, lime and cement werefirst thoroughly mixed in dry state for a period of 10 minutes to uniform blending. Therequired water was then gradually added and the mixing continued for another 5 min.
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME992.3.2.2. Preparation of bricksAll full bricks were made on a bench model, semiautomatic press having a capacity of25 tons, as shown in appendix, to produce bricks of 51×95×203 mm in size under a staticcompaction of 20MPa.2.3.2.4. Testing of bricksAll bricks were dried to the free air for a period of 28, 56 and 90 days. Compressivestrength, density, water absorption and leaching tests of bricks from different mixes ofphosphogypsum, sand, lime and cement with available mixing water content weredetermined.Compressive strength of the units was determined according to ASTM C67 [17]. Testbricks consist of a half brick with full height and width. Flexural strength tests on the brickswere performed according to ASTM C 67 [17]. Test specimens were taken as full-size brickunits.The absorption qualities of brick are taken as a part of the acceptance measurement ofthe durability of the material. ASTM specification C67 describes a method by whichabsorption of building clay brick can be measured. First, the samples are immersed for 24hours in cold water. The amount of water absorbed is then recorded as a percentage of thetotal weight of the dry unit.In order to determine the density of each brick, dry bricks were weighed accuratelyand their volumes were measured.To simulate the action of the weather, the bricks are soaked in water for two days[18]. After 90 days of treatment. In this work the effect of immersion on compressivestrength and flexural strength have been studied.The leaching tests had been performed according to the French norm NF EN 12457-3[19] at an ambient temperature (20 ± 5°C). The specimens (three different samples for eachmix-design) were crushed and an amount of 0.175 kg was taken to be analyzed. The distilledwater was added to obtain a liquid/solid ratio of 10 l/kg.The compressive and flexural strength and speed of sound of phosphogypsum-basedbricks were tested after 28, 56 and 90 days of curing. Water absorption, density, and leachingtest were determined on bricks tested after 28 days of casting.3. TEST RESULTS AND DISCUSSION3.1. Dry densityThe densities of CS-NHL-C-PG full bricks are shown in table 3. These densities rangefrom 1523 to 1670 kg/m3. Therefore the CS-NHL-C-PG full bricks have high density.Table 3.Dry densities (kg/m3) of CS-NHL-C-PG full bricksDry densities (kg/m3)M1 M2 M3 M4 M5 M6 M7 M8 M91535 1564,5 1594 1570 1606 1642,5 1633 1670 1751,53.2.The 24-h cold water absorption of studied bricksThe water absorption is a principal factor for the durability of the product and itsbehavior to natural environment. Table 4 presents the results of the water absorption for theselected percentages of the bricks. It was observed that the water absorption of bricks
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME100decreased with the increase cement contents. Also, it was observed that the values obtainedwere favorable when compared with those of clay bricks (0 to 30%) [20].Table 4 .Water absorption of CS-NHL-C-PG full bricksMix designation Water absorption after 24hr cold water (%)M1 24.65M2 23.78M3 22.02M4 23.3M5 22.07M6 21.46M7 21.52M8 20.7M9 193.3. Compressive strength of studied bricksThe results, obtained as an average of measurements performed on three specimens,are shown in table 5. The BS6073-Part 1 standards [21] require minimum compressivestrengths of 7.0 MPa and 11.7 MPa after a 28-day curing period for load-bearing concretemasonry units. All of the 28-day-cured mixtures described in this study satisfied the BS6073[21] standard for compressive strength.For all the studied cases, the strength of the 90 days cured full bricks was higher than10.3 MPa, which is the minimum strength indicated by the standards [22]. Cement and limeas a source of reactive silica and alumina are given to silicate and aluminate hydrates, whichare responsible for the development of strength.These Figures show also increase in thestrength with the cement additions. This result confirms the water absorption test outcome,where it has been indicated that the addition of cement produces a decrease in the internalpore size. Thus, the brick becomes less porous causing an increase in the mechanicalstrength.Table 5. Compressive strength of CS-NHL-C-PG full bricksMix designation Compressive strength(MPa)(28 days)Compressive strength(MPa)(56 days)Compressive strength(MPa)(90 days)M1 12.48 13.568 13.956M2 13.947 14.79 15.1M3 14.746 15.361 15.553M4 13.4 14.531 14.8M5 14.213 15.228 15.493M6 15.669 16.269 16.462M7 13.9 14.79 15.22M8 14.676 15.703 16.2M9 16.034 16.887 17.3
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue3.4. Flexural strength of studied bricksThe results, obtained as an average of measurements performed on thrare shown in table 6. The code ASTM does not specify a requirement for flexural strength.However the values obtained were fstrength required by BS6073-Part 1 (0.65 MPa) after a 28surpassed by all the samples.Table 6.Flexural strength of CSMix designation flexural strength(MPa)(28 days)M1 7.712M2M3M4 7.895M5M6M7M8M93.5. Behavior immersion of bricks3.5.1. Compressive strength of full bricks after 2 days immersionThe results, obtained as an average of measurements performed on three specimens,are shown in Figs. 1-3. The loss ofgiven in table 7. It is observed that loss in compressive strength decrease withphosphogypsum and cement content. So bricks with more phosphogypsum and cement havebetter compressive strength after 2 days immersionFigure.1 compressive strength of CS0246810121416compresivestrength(MPa)International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME101strength of studied bricksThe results, obtained as an average of measurements performed on three specimens,The code ASTM does not specify a requirement for flexural strength.However the values obtained were favorable when compared with the minimum flexuralPart 1 (0.65 MPa) after a 28-day curing period [21] wichFlexural strength of CS-NHL-C-PG full bricksflexural strength(MPa)(28 days)flexural strength(MPa)(56 days)flexural strength(MPa)(90 days)7.712 8.13 8.258 8.35 8.5058.12 8.77.895 8.332 8.448.16 8.5 8.6048.51 8.827.9 8.332 8.4998.27 8.7 8.8878.56 8.913 9.001of bricksCompressive strength of full bricks after 2 days immersionThe results, obtained as an average of measurements performed on three specimens,. The loss of compressive strength after 2 days of immersion in water ist is observed that loss in compressive strength decrease withphosphogypsum and cement content. So bricks with more phosphogypsum and cement havecompressive strength after 2 days immersion.ressive strength of CS-NHL-C-PG full bricks (phosphogypsum=60%)5 7.5 10cement (%)CSCSiInternational Journal of Advanced Research in Engineering and Technology (IJARET), ISSNJune (2013), © IAEMEee specimens,The code ASTM does not specify a requirement for flexural strength.avorable when compared with the minimum flexural[21] wich wasflexural strength(MPa)(90 days)8.258.5058.88.448.6048.98.4998.8879.001The results, obtained as an average of measurements performed on three specimens,immersion in water ist is observed that loss in compressive strength decrease withphosphogypsum and cement content. So bricks with more phosphogypsum and cement havePG full bricks (phosphogypsum=60%)CSCSi
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, IssueFigure.2 compressive strength of CSFigure.3 compressive strength of CSTable 7. Loss in compressive smixe M1 M2Loss incompressivestrength (%)10.6 8.405101520compressivestrength(MPa)05101520compressivestrength(MPa)International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME102compressive strength of CS-NHL-C-PG full bricks (phosphogypsum=70%)compressive strength of CS-NHL-C-PG full bricks (phosphogypsum=80%)Loss in compressive strength of CS-NHL-C-PG full bricksM3 M4 M5 M6 M7 M87.1 10 7.9 6.5 9.4 7.15 7.5 10cement (%)CSCSi5 7.5 10cement (%)CSCSiInternational Journal of Advanced Research in Engineering and Technology (IJARET), ISSNJune (2013), © IAEMEPG full bricks (phosphogypsum=70%)PG full bricks (phosphogypsum=80%)PG full bricksM8 M97.1 5.9CSCSiCSCSi
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue3.5.2. Flexural strength of full bricks after 2 days immersionThe results, obtained as an average of meashown in Figs. 4-6. The loss of flexural strength after 2 days of immersion in water is givenin table 8. It is observed that loss in flexural strength decrease with phosphogypsum andcement content. So bricks with more phosphogypsum and cement have better behavior toimmersion in water.Figure.4 Flexural strength of CSFigure.5 Flexural strength of CS0246810flexuralstrength(MPa)0246810flexuralstrength(MPa)International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME103Flexural strength of full bricks after 2 days immersionThe results, obtained as an average of measurements performed on three specimens, are. The loss of flexural strength after 2 days of immersion in water is givenis observed that loss in flexural strength decrease with phosphogypsum andth more phosphogypsum and cement have better behavior toFlexural strength of CS-NHL-C-PG full bricks (phosphogypsum=60%)Flexural strength of CS-NHL-C-PG full bricks (phosphogypsum=70%)5 7.5 10cement (%)FSFSi5 7.5 10cement (%)FSFSiInternational Journal of Advanced Research in Engineering and Technology (IJARET), ISSNJune (2013), © IAEMEsurements performed on three specimens, are. The loss of flexural strength after 2 days of immersion in water is givenis observed that loss in flexural strength decrease with phosphogypsum andth more phosphogypsum and cement have better behavior toPG full bricks (phosphogypsum=60%)PG full bricks (phosphogypsum=70%)FSFSiFSFSi
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, IssueFigure.6 Flexural strength of CSTable 8. Loss in flexural strength of CSmixe M1 M2 M3Loss inflexuralstrength(%)11.6 8.49 7.63.6. Leaching testsThe average values of the leachithe selected metal species, i.e., Cd, Cu, Zn, Ni, Pb, and Cr, forbelow the regulatory limits. Thus, this result indicates that PG amended brick specibe considered as non hazardous materials.Table 9.Leaching test results, in mg/kg for L/S = 10 l/kgEléments M1 M2 M3 M4Cr 0.058 0.055 0.14 0.Ni 0.055 0.05 0.04 0.046Zn 0.036 0.034 0.032 0.032Pb 0.085 0.08 0.078 0.081Cu 0.095 0.085 0.083 0.08Cd 0.05 0.047 0.042 0.040246810flexuralstrength(MPa)International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME104rength of CS-NHL-C-PG full bricks (phosphogypsum=80%)Loss in flexural strength of CS-NHL-C-PG full bricksM3 M4 M5 M6 M7 M87.6 8.2 7.3 6.4 6.2 4.5age values of the leaching test are presented in Table 9. The concentrations ofthe selected metal species, i.e., Cd, Cu, Zn, Ni, Pb, and Cr, for all mix-design, were wellthe regulatory limits. Thus, this result indicates that PG amended brick specibe considered as non hazardous materials.Leaching test results, in mg/kg for L/S = 10 l/kgM4 M5 M6 M7 M8 M9Limitvaluesacceptableas inert0.048 0.045 0.037 0.035 0.026 0.02 40.046 0.041 0.033 0.041 0.039 0.035 0.40.032 0.03 0.029 0.028 0.026 0.024 40.081 0.079 0.077 0.078 0.077 0.075 0.50.08 0.082 0.079 0.078 0.076 0.069 20.04 0.02 0.01 0.025 0.01 0.01 0.045 7.5 10cement (%)FSFSiInternational Journal of Advanced Research in Engineering and Technology (IJARET), ISSNJune (2013), © IAEMEPG full bricks (phosphogypsum=80%)M8 M94.5 4The concentrations ofdesign, were wellthe regulatory limits. Thus, this result indicates that PG amended brick specimens canLimitvaluesacceptableas inertLimitvaluesacceptableas nonhazardous50105010501FSi
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME1054. CONCLUSIONBased on the experimental investigation reported in this paper, following conclusionsare drawn:(1) The CS-NHL-C-PG bricks have sufficient strength and have potential as a replacementfor load-bearing concrete masonry units.(2) The increase of the percentages of PG and cement resulted in increase in the compressiveand flexural strength of full bricks after 2 days of immersion in water.(3) Cementations binder with 80% phosphogypsum content shows low loss of compressiveand flexural strength after immersion.(4) Loss of flexural strengths is lower than those of compressive. Therefore the bricksimmersed in water perform better in flexure than in compression.(5) All full bricks specimens can be considered as non hazardous materials.REFERENCES[1] Sfar Felfoul H, Clastres P, Carles GA, Ben Ouezdou M. (2002) Amelioration descaracteristiques du phosphogypse en vue de son utilisation en technique routiere.Dechets Sci Tech; vol. 28, pp. 21–5 [in French].[2] Singh M. (2002) Treating waste phosphogypsum for cement and plaster manufacture.Cem Concr Res; vol. 32; No. 7, pp. 1033–8.[3] Singh M. (2003) Effect of phosphatic and fluoride impurities of phosphogypsum on theproperties of selenite plaster. Cem Concr Res; vol. 33; No. 9, pp. 1363–9.[4] Singh M. (2005) Role of phosphogypsum impurities on strength and microstructure ofserenity plaster. Constr Build Mater; vol. 19; No. 6, pp. 480–6.[5] Mullins GL, Mitchell CC. (1990) Wheat forage response to tillage and sulfur applied asPG. In: Proceedings of the third international symposium on PG, Orlando, USA, vol. I.Publication FIPR no. 01-060-083; pp. 362–75.[6] Potgieter JH, Potgieter SS, McCrindle RI, Strydom CA. (2003) An investigation intothe effect of various chemical and physical treatments of a South Africanphosphogypsum to render it suitable as a set retarder for cement. Cem Concr Res. 33,pp. 1223–7.[7] Altun IA, Sert Y. (2004) Utilization of weathered phosphogypsum as set retarder inPortland cement. Cem Concr Res; vol.34, pp. 677–80.[8] Kacimi L, Simon-Masseron A, Ghomari A, Derriche Z. (2006) Reduction ofclinkerization temperature by using phosphogypsum. J Hazard Mater; vol. B137, pp.129–37.[9] Degirmenci N, Okucu A, Turabi A. (2007) Application of phosphogypsum in soilstabilization. Build Environ; vol. 42, pp. 3393-8.[10] Sunil K. (2003) Fly ash-lime-phosphogypsum hollow blocks for walls and partitions.Building and Environment; vol. 38, pp.291-295.[11] Abalı YK, Yurdusev MA, Zeybek MS, Kumanlıog˘lu AA. (2007) Using PG and boronconcentrator wastes in light brick production. Constr Build Mater ; vol. 21, pp. 52–6.[12] Karray MA, Mensi R. (2000) Etude de la Deformabilite des Poutrelles en Beton Arme abase du Ciment Ultimax. Ann Batiment Travaux Publics;2, pp. 5–14 [in french].[13] Charfi FF, Bouaziz J, Belayouni H. (2000) Valorisation du phosphogypse de Tunisie envue de son utilisation comme substituant au gypse naturel dans la fabrication du ciment.
    • International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN0976 – 6480(Print), ISSN 0976 – 6499(Online) Volume 4, Issue 4, May – June (2013), © IAEME106[14] Moussa D, Crispel JJ, Legrand CL, Thenoz B. (1984) Laboratory study of the structureand compactibility of Tunisian phosphogypsum (Sfax) for use in embankmentconstruction. Resour Conserv; vol. 11; No. 2, pp. 95–116 [in French].[15] Kuryatnyk T, Angulski da Luz C, Ambroise J, Pera J. (2008) Valorization ofphosphogypsum as hydraulic binder. J Hazard Mater; vol. 160, No. 2–3, pp. 681–7.[16] Sfar Felfoul H. (2004) Etude du phosphogypse de Sfax (Tunisie) en vue d’unevalorisation en technique routiere. PhD thesis, Department of Civil Engineering,National Engineering School of Tunis/INSA Toulouse.[17] Ahmadi BH. (1989) Use of high strength by product gypsum bricks in masonryconstruction. PhD dissertation, University of Miami, Coral Gables, Florida, USA. 245p.ASTM international: C62-08, Standard specification for building brick: Solid MasonryUnits Made from Clay.[18] FEKI N., (1991) : Utilisation du phosphogypse en assises de chaussées. Projet de find’études de la filière longue, Génie Géologique, ENIS, 93 p.[19] AFNOR. Lixiviation (2002) – Essai de conformite pour Lixiviation des dechetsfragmentes et des boues. NF EN 12457-3; [in French].[20] Deboucha S, Hashim R, Aziz AA. (2011) Engineering properties of cemented peatbricks Scientific Research and Essays Vol. 6. No. 8, pp. 1732-1739.[21] BS 6073: Part 1: precast concrete masonry units, Part 1. Specification for precastconcrete masonry units. British Standards Institution, 1981.[22] ASTM international: C62-08, Standard specification for building brick: Solid MasonryUnits Made from Clay (2008) 4p.[23] Ghassan Subhi Jameel, “Study The Effect of Addition of Wast Plastic on Compressiveand Tensile Strengths of Structural Lightweight Concrete Containing Broken Bricks asAcoarse Aggregate”, International Journal of Civil Engineering & Technology(IJCIET), Volume 4, Issue 2, 2013, pp. 415 - 432, ISSN Print: 0976 – 6308,ISSN Online: 0976 – 6316.[23] C.Freeda Christy, R.Mercy Shanthi and D.Tensing, “Bond Strength of The BrickMasonry”, International Journal of Civil Engineering & Technology (IJCIET),Volume 3, Issue 2, 2012, pp. 380 - 386, ISSN Print: 0976 – 6308, ISSN Online:0976 – 6316.