Physical-mechanical behaviour and transformations at high temperature in a cement mortar with waste glass as aggregate

Manuscript Details Manuscript number JOBE_2019_2502_R1 Title PHYSICAL-MECHANICAL BEHAVIOUR AND TRANSFORMATIONS AT HIGH TEMPERATURE IN A CEMENT MORTAR WITH WASTE GLASS AS AGGREGATE Article type Research Paper Abstract The replacement of natural aggregates with different recycled materials in mortars and concretes has fostered significant progress in the construction sector, thus reducing the need to extract virgin raw materials. The incorporation of household glass waste in cement mortar was studied to determine its behaviour as a replacement for sand; this paper studies its mechanical properties at room temperature and after a 800ºC heating process. The results were evaluated using Student’s t-test. Changes in thermal properties through the addition of glass to mortars were also studied. Various proportions of ground glass were used to replace the aggregate. Compression and flexural resistances presented statistically significant differences. Mortars with ground glass aggregate also showed a clear improvement in the thermal conductivity coefficient and thermal diffusivity, reflecting a positive behaviour in relation to their thermal response and insulation capacity. Internal mortar structures were not affected by the incorporation of ground glass. Keywords mortar; crushed glass; high temperatures; thermal conductivity; hardened properties Taxonomy Heat Conduction, Waste Recycle System, Materials Mechanics Manuscript category Building materials Corresponding Author VICENTE FLORES-ALÉS Corresponding Author's Institution E.T.S.Ingeniería de Edificación. Universidad de Sevilla Order of Authors VICENTE FLORES-ALÉS, Juan Manuel Alducin-Ochoa, Juan Jesus Martin-Del- Rio, Torres González Marta, Victor Jimenez Bayarri Suggested reviewers Jesús Alberto Pulido-Arcas, Servando Chinchón, Ariel Bobadilla, Pedro J. Sánchez-Soto Submission Files Included in this PDF File Name [File Type] Cover letter.doc [Cover Letter] Responses to reviewers.docx [Response to Reviewers] MANUSCRIPT_RV.docx [Revised Manuscript with Changes Marked] HIGHLIGHTS.docx [Highlights] MANUSCRIPT.docx [Manuscript File] FIGURE 1.TIF [Figure] FIGURE 2.TIF [Figure] FIGURE 3.TIF [Figure] FIGURE 4.TIF [Figure] FIGURE 5.TIF [Figure] FIGURE 6.TIF [Figure] FIGURE 7.tif [Figure] FIGURE 8A.TIF [Figure] FIGURE 8B.TIF [Figure] FIGURE 9A.TIF [Figure] FIGURE 9B.TIF [Figure] FIGURE 10a.TIF [Figure] FIGURE 10b.TIF [Figure] FIGURE 10c.TIF [Figure] FIGURE 10d.TIF [Figure] Table 1.docx [Table] Table 2.docx [Table] Table 3.docx [Table] Table 4.docx [Table] Table 5.docx [Table] Table 6.docx [Table] Conflict of interest declaration.docx [Conflict of Interest] Author Statement.docx [Author Statement] To view all the submission files, including those not included in the PDF, click on the manuscript title on your EVISE Homepage, then click 'Download zip file'. Research Data Related to this Submission There are no linked research data sets for this submission. The following reason is given: Data will be made available on request Journal of Building Engineering Dear Editor: Let me introduce myself, my name is Vicente Flores-Alés and I am a Material Science Lecturer at the University of Sevilla (Spain). I submit the manuscript entitled “Replacement of aggregate with crushed glass in a cement mortar. The effect on physical-mechanical behaviour and transformations at high temperature” for your considerations in order to be published in Journal of Building Engineering. Look forward to your favourable consideration. Most sincerely, Vicente Flores-Alés University of Seville Plan of the manuscript: “Replacement of aggregate with crushed glass in a cement mortar. The effect on physical-mechanical behaviour and transformations at high temperature” Abstract Key-words 1. Introduction 2. Objectives 3. Materials and methodology 4. Experimental development and discussion of results 4.1 Characterization of components 4.2 X-Ray diffraction 4.3 Mechanical capacities and statistical analysis of results by Student’s t-Test 4.4 Physical properties 4.5 Thermal properties 4.6 Analysis of internal structures by SEM 5. Conclusions Acknowledgements References Authors: V. Flores-Alés (*), J.J. Martín-del-Río, J.M. Alducin-Ochoa, M. Torres- González, V.Jiménez-Bayarri *Corresponding author Mailing address: V. Flores-Alés E.T.S.I.E. Avda/ Reina Mercedes, nº4A 41012-Sevilla ESPAÑA E-mail address: [email protected] Phone number: 34 954556656 Fax: 34 954556691 Reviewer 2 The authors would like to thank the reviewers their helpful comments, which have improved the first version of this paper The title perceived as two separate sentences given as "REPLACEMENT OF AGGREGATE WITH CRUSHED GLASS IN A CEMENT MORTAR. THE EFFECT ON PHYSICALMECHANICAL BEHAVIOUR AND TRANSFORMATIONS AT HIGH TEMPERATURE" can be combined and shortened without distort its meaning Title has been changed and shortened according with the reviewer suggestion. Since “Characterization of components” is related to the properties of the materials used, it is more appropriate to be included in "MATERIALS AND METHODOLOGY” We have made corrections in accordance with the reviewer´s comment. The heating process should be detailed in the methodology section. Describe the type of cooling. The curing time of the specimens should be clarified (28?, 90?). How many days were the specimens cured before heating? Mechanical tests were performed immediately after heating? The curing time is indicated in line 120. We have detailed the cooling process. Mechanical test were carried out immediately after cooling process. We have clarified the text in this sense. Why use a single temperature as the high temperature when using different proportions of glass? The reason why 800 C is selected should be explained in the relevant section. In this research phase we have considered the percentage of glass as the only variable, according to the reviewer's indication it is planned to study the evolution of the materials at different temperatures. A more extended explanation and references about the selected temperature has been given. Glass was used instead of sand. Why is XRD analysis performed since it is not used as a binder? What is the expected change in the chemical structure? The answers to the questions can be given at the appropriate places in the manuscript. Mineralogical characterization confirms that calcium silicates from the cement do not develop unexpected variations after heating, neither there are new phases formation by the thermal activation of the amorphous silicates of the glass (point 4.2). The expected change in the chemical structure has been detailed in point 4.5. Only the results of the statistical evaluation are given. No comments were made on the causeeffect relationship. Comments are important for the originality of the study A paragraph has been added and hopefully improved, including new references. How were the components identified in microstructure analysis with SEM? How can components be estimated without EDX or EDS analysis? The reviewer is right. This question has been added in the methodology. 1 1PHYSICAL-MECHANICAL BEHAVIOUR AND TRANSFORMATIONS AT HIGH 2TEMPERATURE IN A CEMENT MORTAR WITH WASTE GLASS AS AGGREGATE 3 4ABSTRACT 5The replacement of natural aggregates with different recycled materials in mortars and 6concretes has fostered significant progress in the construction sector, thus reducing the 7need to extract virgin raw materials. The incorporation of household glass waste in 8cement mortar was studied to determine its behaviour as a replacement for sand; this 9paper studies its mechanical properties at room temperature and after a 800ºC heating 10 process. The results were evaluated using Student’s t-test. Changes in thermal 11 properties through the addition of glass to mortars were also studied. Various 12 proportions of ground glass were used to replace the aggregate. The resistance values 13 presented statistically significant differences. Mortars with ground glass aggregate also 14 showed a clear improvement in the thermal conductivity coefficient and thermal 15 diffusivity, reflecting a positive behaviour in relation to their thermal response and 16 insulation capacity. Internal mortar structures were not affected by the incorporation of 17 ground glass. 18 19 KEYWORDS mortar; crushed glass; high temperatures; thermal conductivity; hardened 20 properties 21 22 23 1. INTRODUCTION 24 25 The incorporation of by-products or inert wastes in mortars and concrete as substitutes 26 for natural aggregate is a valid strategy to minimize impacts in different industrial 27 processes due to increasing waste production [1]. The replacement of aggregates with 28 various recycled materials has resulted in significant progress in the construction 29 sector, thus reducing the need to extract virgin aggregates. The materials used most 30 commonly as replacement aggregates include recycled concrete [2, 3], recycled glass, 31 scrap tyres [4,5], plastics and by-products of paper and other industries [6-8]. These 32 incorporated materials must be inert with respect to other components of the 33 conglomerate, must not cause degradation reactions and guarantee adequate 34 durability [9], and they must not adversely affect the rheological behaviour of the fresh 35 material and must comply with resistance standards. 36 Considerable scientific research has been conducted in this area, always with the 37 ultimate aim of reducing solid waste emissions by promoting waste reuse. Romero [10] 38 conducted an in-depth analysis of the durability of concrete and the environmental 39 behaviour of mixtures with aggregates incorporating recycled hazardous waste. The 40 use of waste to substitute fine aggregate is relatively common considering that it has 41 potentially less impact on mechanical resistance; hence, its use is not excessively 42 problematic provided the physicochemical stability of components and final properties 43 is guaranteed. 2 44 The option of using crushed glass aggregates has been widely studied from different 45 perspectives due to the high production of glass as domestic and industrial waste [11]. 46 Attention must be drawn to research carried out on the puzzolanity and cementitious 47 activity of crushed glass powder [12-16]. Glass waste as a partial substitute for fine 48 aggregate has also been the subject of numerous studies that examine fulfilment of the 49 basic requirements of a mortar or concrete cement and, in some cases, the 50 improvement of certain physical [17-19] and chemical [20] properties. 51 The disparity of research describing the behaviour of recycled mortars with partial 52 replacement of aggregate with crushed glass is particularly striking. Although all 53 authors agree on the viability of substitution and on the improvement of basic 54 properties, no consensus has been reached regarding the optimal substitution 55 percentages, the level of improvement of the final product, the optimization of 56 mechanical characteristics, etc. [21-24]. An interesting and widely described aspect is 57 the improvement of thermal behaviour due to the decrease in the thermal conductivity 58 coefficient of recycled mortars with glass aggregate [18-19, 24-26], although it also 59 reveals a disparity in the improvement margins described. It would appear that these 60 differences are attributable to the type of cements employed and the characteristics of 61 the aggregates and incorporated additives, making it impossible to establish unitary 62 and homogeneous behaviour in mortars recycled with glass aggregate, and only 63 allowing behavioural trends to be described. The precise behaviour of specific mortars 64 should be verified in each case. 65 The mechanical behaviour of the samples analysed in this study at both room 66 temperature and high temperature is described. An in-depth study was carried out to 67 characterize their properties and establish relationships with the behaviours identified. 68 2. OBJECTIVES 69 70 This study aimed to examine the mechanical behaviour of a cement mortar (dosage 71 1:3) with various partial substitutions of aggregate with crushed glass from domestic 72 waste. Additionally, in view of the observed improvement in thermal conductivity 73 coefficients afforded by glass to mortars, a broad characterization of the material was 74 carried out. Based on these data, behaviour at high temperature (800ºC) was studied 75 in order to establish relationships between the characteristics of the material and its 76 physical-mechanical behaviour. The temperature of 800ºC was used as the test 77 temperature since at that temperature, the characteristics of a building mortar are 78 completely lost [27]. 79 3. MATERIALS AND METHODOLOGY 80 81 3.1 Starting materials 82 The following materials were used to manufacture the mortars: 83 - CEBASA CEM IV/B(V) 32.5N cement (recommended), in accordance with the 84 manufacturer's instructions (http://www.cebasa.com), for environments of certain 3 85 aggressiveness; this circumstance is interesting insofar as glass also provides 86 certain improvements in durability against aggressive chemical agents [23]. 87 - Standard sand provided by the Eduardo Torroja Institute (CEN Standard Sand 88 EN 196-1:2018) [28]. Particle size less than 2 mm and SiO2 content greater than 89 99% [29]. 90 - Granulated glass from domestic waste, mostly common containers; this material 91 was crushed in a jaw crusher and sieved to a particle size of less than 2 mm [19]. 92 The mixtures were kneaded according to a 1:3 dosage (cement:aggregate) following 93 the specifications of the UNE-EN 196-1 standard (Table 1) and maintaining the same 94 cement content, the same amount of water and the same maximum grain size and 95 particle size distribution. 96 Various proportions of ground glass were used to replace the aggregate (Figure 1). 97 The samples were designated as follows: RM (reference mortar), M10 (10% 98 substitution), M25 (25% substitution), M50 (50% substitution). The specimens 99 subjected to 800°C were called RMhT, M10hT, M25hT and M50hT, respectively. 100 101 102 103 104 105 106 Figure 1. Specimens with different crushed glass substitutes 107 108 109 110 Table 1. The dosage of components for each sample 111 CEMENT (gr) SAND (gr) GLASS (gr) WATER (cm3) RM M10 M25 M50 900 900 900 900 2700 2430 2025 1350 - 270 675 1350 600 600 600 600 112 113 3.2 Methodology 114 Samples were previously validated according to their docility to ensure their fluidity 115 complied with the workability requirements established in the UNE-EN 13395-1 116 standard [30]. 4 117 Once the dosages were validated, series of 12 prismatic specimens of 40x40x160mm 118 were prepared for each type, i.e. the reference mortar and substitutions with 10%, 25% 119 and 50% crushed glass. The specimens were manufactured in accordance with UNE- 120 EN 196-1 standard specifications and cured for 28 days. 121 Materials were characterized at room temperature and after a heating at 800ºC 122 followed by cooling into the oven. This temperature is commonly used as a value that 123 can reach a concrete structure in a fire and from which there is a practically complete 124 loss of mechanical properties [27, 31, 32]. 125 The experimental procedure covered the following points: 126 - Chemical characterization of the components by X-ray fluorescence, in a 127 Panalytical X-ray fluorescence spectrometer (AXIOS) with Rh tube for elemental 128 solid sample analysis. 129 - Mineralogical characterization of mortars by X-rays diffraction, in a Bruker-AXS 130 diffractometer model D8I-A25, equipped with a copper filament Cu Kα 131 (λ=1.5405Ǻ), with Bragg-Bentano θ-θ configuration, nickel filter and Lynxeye 132 linear detector, using the powder technique. 133 - Determination of apparent density and open porosity of the samples by a vacuum 134 method in accordance with the UNE-EN-1936:2007 standard [29]. To calculate 135 thermal conductivity, apparent geometric density was determined by mercury 136 porosimetry (Pore Master 60GT). 137 - Determination of the mechanical resistance of the mortars to flexural and 138 compression strength in accordance with the UNE-EN 196-1:2018 standard with 139 a load speed of 50N/s until breakage. Student’s t-test was used to detect 140 significant differences in mechanical resistance between the resistance values 141 obtained in the reference specimens and those obtained in the specimens with 142 glass aggregate, establishing a significance level of α=0.01. This statistical model 143 is valid for normal distributions with small sample sizes [33,34]. 144 - Study of the thermal conductivity of the mortars was calculated from geometric 145 density by differential scanning calorimetry (MDSC) at 30ºC, in order to verify the 146 influence on thermal properties of the substitution of sand by glass aggregate. 147 [35]. Thermal diffusivity (cm2/s) and thermal conductivity (W/m·K) were measured 148 on Linseis measuring equipment (LFA 1600) and a DSC Q20-TA. 149 - Differential Thermal Analysis (DTA) and Thermogravimetry (DTA-TG) were 150 performed on the mortars in a SDT-Q600 differential scanning calorimeter (TA 151 Instruments) to obtain kinetic data on the energetic behaviour of the materials. 152 - Structural analysis of mortars was carried out by electron microscopy (SEM) in a 153 FEI-Teneo microscope equipped with an energy-dispersive X-ray (EDX) 154 microprobe, a beryllium ATW2 window and specific software (Oxford INCA) for 155 semiquantitative chemical analyses. The samples were prepared by gold 156 sputtering. 157 3.3 Characterization of components 158 The chemical composition of the cement obtained by FRX is shown in Table 2. 159 Table 2 Chemical composition of major components of cement and glass expressed in percentages (%). 160 5 SiO2 Al2O3 Fe2O3 MnO MgO CaO Na2O K2O TiO2 P2O5 SO3 PC Cement 29.36 15.83 2.97 0.05 1.37 43.22 0.18 0.81 0.80 0.81 2.36 4.85 Glass 71.05 1.50 0.19 - 0.76 11.38 13.19 0.72 - - - 0.10 161 162 The different fractions considered in the UNE EN 933-1:2012 standard (0.063, 0.125, 163 0.250, 0.50, 1.00, 2.00mm) [30] were separated in order to prepare a continuous 164 particle size of maximum compactness in accordance with Fuller's curve (Figure 2). 165 166 Figure 2. Aggregate particle size of crushed glass 167 168 169 4. EXPERIMENTAL DEVELOPMENT AND DISCUSSION OF RESULTS 170 4.1 X-Ray diffraction 171 The diffractograms obtained at 28 days for the non-heated samples (M50, M25, M10 172 and RM) were relatively similar, without noteworthy variations between the reference 173 sample (RM) and those to which glass fractions were added (M50, M25 and M10). 174 Figure 3 shows the main hydration products such as portlandite and ettringite in the X- 175 ray diffractograms. At this setting age, characteristic peaks of the main anhydrous 176 products in the hydration process were still observed, forming hydrated silicates, which 177 are difficult to identify in the diffractograms due to their low crystallinity and the 178 superposition of the peaks between the hydrated anhydrous components [36]. 179 Quartz, muscovite, orthoclase, albite and hematite originated from the sand used to 180 prepare the mortars. Calcite may be assigned to the CaCO3 from the carbonated 181 portlandite of the cement or even to any carbonated fraction of the aggregate. 12 351 352 Figure 9. SEM micrographs of calcium silicates (M10hT). 353 354 355 356 Figure 10. SEM micrographs of calcium oxide crystals. 357 358 359 360 5. CONCLUSIONS 361 362 The incorporation of glass represents an obvious ecological alternative to natural 363 aggregates. As a substitute for aggregate in cement mortars, it reduces density, thus 364 helping to reduce the overall weight of the mortar and/or concrete construction 365 elements. 366 The resistance values presented statistically significant differences. However, 367 according to the results of this and other similar studies, it is not possible to conclude 368 that these materials display homogenous mechanical behaviour, since this is strongly 369 determined by the components, dosage and manufacturing process of the test pieces. 370 The statistical analysis of mortars resistance broadly revealed the incidence of the 371 incorporation of glass aggregate on the mechanical capacities of the conglomerate 372 evaluated. Based on a comparison of flexural resistance values obtained for the 373 reference mortar with the results obtained in the other specimens, it was concluded 374 that the improvement in resistance was not significant, with the exception of the 375 samples with a 25% replacement. However, despite their loss of resistance, samples 376 with replacement of natural aggregates subjected to heating at 800ºC showed a 377 significant improvement in resistance with respect to the reference sample. From 378 observations of the compression resistance values obtained for the reference mortar 379 and samples with crushed glass, it was concluded that the decrease in resistance was 380 significant, as for the specimens subjected to 800°C. No improvement was observed 381 between the reference mortar and the other samples, except for the specimens with a 382 10% replacement, but this was not significant. 13 383 The mortars with crushed glass aggregate showed a clear improvement in thermal 384 properties, displaying positive behaviour in relation to their thermal response and 385 insulation capacity. This behaviour was particularly influenced by thermal diffusivity. 386 Internal structure undergoes changes inherent to heating effects, as revealed by the 387 mineralogical analyses. However, it was not affected by the incorporation of crushed 388 glass. No faults were observed in the aggregate/paste interfaces in the samples tested 389 at room temperature, nor in the samples tested at 800ºC. 390 ACKNOWLEDGMENTS 391 392 The authors wish to express their gratitude to CITIUS at the University of Seville for the 393 use of the laboratories for the characterization analyses. 394 395 REFERENCES 396 397 [1] Y. Meng, T.Ch. Ling, K. Hung Mo, Recycling of wastes for value-added applications 398 in concrete blocks: An overview. Resources, Conserv. and Recy., 138 (2018) 298312. 399 https://doi.org/10.1016/j.resconrec.2018.07.029 400 [2] I.B. Topçu, M. Canbaz, Properties of concrete containing waste glass, Cem. Conc. 401 Res., 34 (2004) 267274. https://doi.org/10.1016/j.cemconres.2003.07.003 402 [3] D. Han, Y. Yang, C. Ying, Z. Sierens, H. Fan, J. Li, Efficient recycling and reuse of 403 waste concrete on a construction site, Int. Concrete Abstracts Portal, 326 (2018) 404 38.138.10. 405 [4] F. Valadares, M. Bravo, J. de Brito, Concrete with used tire rubber aggregates: 406 mechanical performance. ACI Mater. J. 109–M26 (2012) 283–292. 407 [5] Li J., M. Saberian, B. T. Nguyen, Effect of Crumb Rubber on Mechanical Properties 408 of Crushed Recycled Pavement Materials. Jour. Environmental Management 218 409 (2018) 291299. https://doi.org/10.1016/j.jenvman.2018.04.062 410 [6] M.N. Gaikwad, A. Gunjawate Shubham, Y. Hole Gannesh, M. Kadam Mangesh, A. 411 Ghorpade Pratik, Experimental study on plastic waste as a course aggregate for 412 structural concrete. Int. Jour. Recent and Innovation Trends in Computing and 413 Communication 6 (2018) 6367. 414 [7] C. Meyer, The greening of the concrete industry. Cement and Concrete Composites 415 31 (2013) 601605 https://doi.org/10.1016/j.cemconcomp.2008.12.010 416 [8] N. Karakaš, K. Strukar, T. Kalman Šipoš, I. Miličević, Potential use of recycled 417 aggregate in structural concrete elements. 9th International Congress of Croatian 418 Society of Mechanics (2018). 419 [9] C. Lobo, New perspective on concrete durability. Concrete InFocus, Spring (2007) 420 2430. 14 421 [10] D. Romero, Concrete durability and environmental performance of mixtures 422 containing recycled hazardous waste aggregates, PhD Thesis, University of Miami 423 (2013). 424 [11] R. Vandhiyan, K. Ramkumar, R. Ramya, Experimental Study on Replacement of 425 Cement by Glass Powder. Int. Jour. Engineering Research and Technology (IJERT) 426 Vol.2, 5 (2013). 427 [12] M. Saillio, F. Frohard, T. Chaussadent, L. Divet, A. Tagnit-Hamou, Durability of 428 concrete with alternative supplementary cementitious materials. 10th ACI/RILEM 429 International Conference on Cementitious Materials and Alternative Binders for 430 Sustainable Concrete (2017), p.19. 431 [13] E. L. Tucker, C. C. Ferraro, S. J. Laux, T. G. Townsend, Economic and life cycle 432 assessment of recycling municipal glass as a pozzolan in portland cement concrete 433 production. Resources, Conserv. and Recy., 129 (2018) 240–247. 434 https://doi.org/10.1016/j.resconrec.2017.10.025 435 [14] Y. Jani, W. Hogl, Waste glass in the production of cement concrete-A review. Jour. 436 Environmental Chem. Eng., 2 (2014) 17671775, 437 http://dx.doi.org/10.1016/j.jece.2014.03.016 438 [15] N. Roz-Ud-Din, S. Parviz, Strength durability of recycled aggregate concrete 439 containing milled glass as partial replacement for cement, Constr. Build. Mater., 29 440 (2012) 368377. https://doi.org/10.1016/j.conbuildmat.2011.10.061 441 [16] A. Shayan, A. Xu, Performance of glass powder as a pozzolanic material in 442 concrete: A field trial on concrete slabs, Cem. Conc. Res., 36 (2006) 457–468. 443 https://doi.org/10.1016/j.cemconres.2005.12.012 444 [17] K. Afshinnia P. R. Rangaraju, Impact of combined use of ground glass powder 445 crushed glass aggregate on selected properties of Portland cement concrete. Constr. 446 Build. Mater., 117 (2016) 263272, https://doi.org/10.1016/j.conbuildmat.2016.04.072 447 [18] M. J. Terro, Properties of concrete made with recycled crushed glass at elevated 448 temperatures, Building Environment, 41 (2006) 633–639. 449 https://doi.org/10.1016/j.buildenv.2005.02.018 450 [19] V. Flores-Alés, V. Jiménez-Bayarri, A. Pérez-Fargallo, Influencia de la 451 incorporación de vidrio triturado en las propiedades y el comportamiento a alta 452 temperatura de morteros de cemento, Bol. Soc. Esp. Cerámica y Vidrio (2018) 257-265 453 https://doi.org/10.1016/j.bsecv.2018.03.001 454 [20] S. M. H Shafaatian , J. R. Wright , F. Rajabipour, Performance of recycled soda– 455 lime glass powder in mitigating alkali–silica reaction. Green Materials (2018) 456 https://doi.org/10.1680/jgrma.18.00032 457 [21] K. Rashid, R. Hameed, H. A. Ahmad, A. Razzaq, M. Ahmad, A. Mahmood, 458 Analytical framework for value added utilization of glass waste in concrete: Mechanical 459 and environmental performance. Waste Management, 79 (2018) 312–323. 460 https://doi.org/10.1016/j.wasman.2018.07.052 15 461 [22] B.P. Seung, B. C. Lee, J. H. Kim. Studies on mechanical properties of concrete 462 containing waste glass aggregate. Cem. Conc. Res., 34 (2004) 2181–2189. 463 https://doi.org/10.1016/j.cemconres.2004.02.006 464 [23] D. Serpa, A. Santos Silva, D. Soares, M. B. Santos, J. de Brito, Behaviour of glass 465 in cement-based materials: its role on ASR, Material Science Forum, 730-732 (2012) 466 415–420. https://doi.org/10.4028/www.scientific.net/MSF.730-732.415 467 [24] A. S. Khalil, M. A. Mahmoud, A. AL-Hathal, M. K. Jawad, B. M. Mozahim, The 468 effect of replaced recycled glass on thermal conductivity and compression properties of 469 cement. Journal of Physics: Conference Series, 1003 (2018). 470 http://dx.doi.org/10.1088/1742-6596/1003/1/012127 471 [25] A. Al-Sibahy, R. Edwards, Mechanical and thermal properties of novel lightweight 472 concrete mixtures containing recycled glass and metakaolin. Constr. Build. Mater., 31 473 (2012) 157167, https://doi.org/10.1016/j.conbuildmat.2011.12.095 474 [26] R. R. Krishnamoorthy, J. A. Zujip, Thermal Conductivity and Microstructure of 475 Concrete Using Recycle Glass as a Fine Aggregate Replacement. International Journal 476 of Emerging Technology and Advanced Engineering, 3 (2013), 463471. 477 [27] Y. Pei, Sh. Li, F. Agostini, F. Skoczylas, Effects of severe heating and rehydration 478 on poro-mechanical properties of a mortar, Cem. Conc. Res., 115 (2019) 460-471 479 https://doi.org/10.1016/j.cemconres.2018.09.020 480 [28] UNE-EN 196-1:2018 Métodos de ensayo de cementos. Parte 1: Determinación 481 de resistencias. 482 [29] UNE-EN 1936:2007 Métodos de ensayo para piedra natural. Determinación de la 483 densidad real y aparente y de la porosidad abierta y total. 484 [30] UNE-EN 13395-1:2002 Productos y sistemas para la protección y reparación de 485 estructuras de hormigón. Métodos de ensayo. Determinación de la trabajabilidad. 486 Parte 1: Ensayo de escurrimiento de los morteros tixotrópicos. 487 [31] E.T.Stepkowska, J.M. Blanes, F. Franco, C. Real, J.L. Pérez-Rodriguez, Phase 488 transformation on heating of an aged cement paste. Thermochimica Acta, 420(2004) 489 79-87 https://doi.org/10.1016/j.tca.2003.11.057 490 [32] M. Heikal, Effect of temperature on the structure and strength properties of cement 491 pastes containing fly ash alone or in combination with limestone. Ceramics Silikaty, 492 50(2006) 167-177 493 [33] R.E. Walpole, R. H. Myers, Sh. L. Myers, K. Ye, Probability and statistics for 494 engineers and scientists (9th Ed.) Pearson (2012) 246-250. 495 [34] A. Nieves, F. Domínguez, F. Flores, A. Gutiérrez, Probabilidad y estadística para 496 ingeniería (1ª Ed) México: McGrawHill (2010) 380-387. 497 [35] J. Blumm, A. Lindeman, B. Niedrig, Measurement of the thermophysical properties 498 of an NPL thermal conductivity stard Inconel 600, High Temp. Press., 35/36, 621-626. 499 https://doi.org/10.1068/htjr145 16 500 [36] F. Kontoleontosa , P. Tsakiridisb, A. Marinosa , N. Katsiotisa , V. Kaloidasc , M. 501 Katsioti dry-grinded ultrafine cements hydration. physicochemical and microstructural 502 characterization, Materials Research 16(2013) 404-416 https://doi.org/10.1590/S1516- 503 14392013005000014. 504 [37] M. A. Tantawy, Effect of high temperatures on the microstructure of cement paste. 505 Jour. Mat. Sci. and Chem. Eng., 5 (2017) 33-48 506 https://doi.org/10.4236/msce.2017.511004 507 508 [38] G.F. Peng, Z.S. Huang, Change in microstructure of hardened cement paste 509 subjected to elevated temperatures. Constr. Build. Mater., 22(2008) 593-599 510 [39] A. Mohajerani, J. Vajna, T.H.H. Cheung, H. Kurmus, A. Arulrajah, S. Horpibulsuk, 511 Practical recycling applications of crushed waste glass in construction materials: A 512 review, Constr. Build. Mater., 156 (2017), 443-467. 513 https://doi.org/10.1016/j.conbuildmat.2017.09.005 514 [40] M. Batayneh, M. Iqbal, A. Ibrahim, Use of selected waste materials in concrete 515 mixes. Waste Manage., 27 (2007), 1870-1876. 516 https://doi.org/10.1016/j.wasman.2006.07.026 517 [41] M. Adaway, W. Ying, Recycled glass as a partial replacement for fine aggregate in 518 structural concrete-Effects on compressive strength. Electronic Jour. Struct. Eng., 14 519 (2015), 116-122. 520 [42] M. Aly, M.S.J. Hashmi, A.G. Olabi, M. Messeiry, A.I. Hussainc, Effect of nano clay 521 particles on mechanical, thermal and physical behaviours of waste-glass cement 522 mortars. Materials Science and Engineering A 528 (2011) 7991–7998 523 doi:10.1016/j.msea.2011.07.058 524 [43] J. Wang, L. Yuan, N. Wang, W. Jiang, Z. He Experimental study on mechanical 525 performance of lightweight aggregate concrete after high temperature heating.J Nat 526 Disasters, 23 (2014) 258-263 527 528 [44] W. Tan, G. Zhu, Y. Liu, et al. Effects and mechanism research of the crystalline 529 state for the semi-crystalline calcium silicate Cem. Concr. Res., 72 (2015) 69–75. 530 https://doi.org/10.1016/j.cemconres.2015.02.020 531 [45] T.V. Vakalova, V.M. Pogrebenkov, N.P. Karionova, Solid–phase synthesis of 532 wollastonite in natural and technogenic siliceous stock mixtures with varying levels of 533 calcium carbonate component. Ceramics International 42 (2016) 16453–16462. 534 https://doi.org/10.1016/j.ceramint.2016.06.060 535 [46] J. Zou, C. Guo, Y. Jiang, C. Wei, F. Li, Structure, morphology and mechanism 536 research on synthesizing xonotlite fiber from acid-extracting residues of coal fly ash 537 and carbide slag. Materials Chemistry and Physics. 172 (2016) 121–128. 538 https://doi.org/10.1016/j.matchemphys.2016.01.050 539 540 [47] G. Wang, C. Zhang, B. Zhang, Q. Li, Z. Shui, Study on the high-temperature 541 behaviour and rehydration characteristics of hardened cement paste, Fire 542 Mater, 39 (2015) 741–750. https://doi.org/10.1002/fam.2269 17 543 544 [48] M.I. Romero-Hermida, A.M. Borrero-López, F.J. Alejandre, V. Flores-Alés, A. 545 Santos, J.M. Franco, L. Esquivias, Phosphogypsum waste lime as a promising 546 substitute of commercial limes: A rheological approach, Cem. & Conc. Composites, 95 547 (2019) 205-216. https://doi.org/10.1016/ j.cemconcomp.2018.11.007 HIGHLIGHTS The use of inert wastes in mortars to minimize the environmental impacts. Crushed glass as a substitute for sand in mortars improves its thermal behaviour. Recycled glass mortars do not show homogeneous mechanical behaviour. Internal mortar structures show correct glass/binder interface cohesion. 1 1PHYSICAL-MECHANICAL BEHAVIOUR AND TRANSFORMATIONS AT HIGH 2TEMPERATURE IN A CEMENT MORTAR WITH WASTE GLASS AS AGGREGATE 3 4ABSTRACT 5The replacement of natural aggregates with different recycled materials in mortars and 6concretes has fostered significant progress in the construction sector, thus reducing the 7need to extract virgin raw materials. The incorporation of household glass waste in 8cement mortar was studied to determine its behaviour as a replacement for sand; this 9paper studies its mechanical properties at room temperature and after a 800ºC heating 10 process. The results were evaluated using Student’s t-test. Changes in thermal 11 properties through the addition of glass to mortars were also studied. Various 12 proportions of ground glass were used to replace the aggregate. The resistance values 13 presented statistically significant differences. Mortars with ground glass aggregate also 14 showed a clear improvement in the thermal conductivity coefficient and thermal 15 diffusivity, reflecting a positive behaviour in relation to their thermal response and 16 insulation capacity. Internal mortar structures were not affected by the incorporation of 17 ground glass. 18 19 KEYWORDS mortar; crushed glass; high temperatures; thermal conductivity; hardened 20 properties 21 22 23 1. INTRODUCTION 24 25 The incorporation of by-products or inert wastes in mortars and concrete as substitutes 26 for natural aggregate is a valid strategy to minimize impacts in different industrial 27 processes due to increasing waste production [1]. The replacement of aggregates with 28 various recycled materials has resulted in significant progress in the construction 29 sector, thus reducing the need to extract virgin aggregates. The materials used most 30 commonly as replacement aggregates include recycled concrete [2, 3], recycled glass, 31 scrap tyres [4,5], plastics and by-products of paper and other industries [6-8]. These 32 incorporated materials must be inert with respect to other components of the 33 conglomerate, must not cause degradation reactions and guarantee adequate 34 durability [9], and they must not adversely affect the rheological behaviour of the fresh 35 material and must comply with resistance standards. 36 Considerable scientific research has been conducted in this area, always with the 37 ultimate aim of reducing solid waste emissions by promoting waste reuse. Romero [10] 38 conducted an in-depth analysis of the durability of concrete and the environmental 39 behaviour of mixtures with aggregates incorporating recycled hazardous waste. The 40 use of waste to substitute fine aggregate is relatively common considering that it has 41 potentially less impact on mechanical resistance; hence, its use is not excessively 42 problematic provided the physicochemical stability of components and final properties 43 is guaranteed. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 2 44 The option of using crushed glass aggregates has been widely studied from different 45 perspectives due to the high production of glass as domestic and industrial waste [11]. 46 Attention must be drawn to research carried out on the puzzolanity and cementitious 47 activity of crushed glass powder [12-16]. Glass waste as a partial substitute for fine 48 aggregate has also been the subject of numerous studies that examine fulfilment of the 49 basic requirements of a mortar or concrete cement and, in some cases, the 50 improvement of certain physical [17-19] and chemical [20] properties. 51 The disparity of research describing the behaviour of recycled mortars with partial 52 replacement of aggregate with crushed glass is particularly striking. Although all 53 authors agree on the viability of substitution and on the improvement of basic 54 properties, no consensus has been reached regarding the optimal substitution 55 percentages, the level of improvement of the final product, the optimization of 56 mechanical characteristics, etc. [21-24]. An interesting and widely described aspect is 57 the improvement of thermal behaviour due to the decrease in the thermal conductivity 58 coefficient of recycled mortars with glass aggregate [18-19, 24-26], although it also 59 reveals a disparity in the improvement margins described. It would appear that these 60 differences are attributable to the type of cements employed and the characteristics of 61 the aggregates and incorporated additives, making it impossible to establish unitary 62 and homogeneous behaviour in mortars recycled with glass aggregate, and only 63 allowing behavioural trends to be described. The precise behaviour of specific mortars 64 should be verified in each case. 65 The mechanical behaviour of the samples analysed in this study at both room 66 temperature and high temperature is described. An in-depth study was carried out to 67 characterize their properties and establish relationships with the behaviours identified. 68 2. OBJECTIVES 69 70 This study aimed to examine the mechanical behaviour of a cement mortar (dosage 71 1:3) with various partial substitutions of aggregate with crushed glass from domestic 72 waste. Additionally, in view of the observed improvement in thermal conductivity 73 coefficients afforded by glass to mortars, a broad characterization of the material was 74 carried out. Based on these data, behaviour at high temperature (800ºC) was studied 75 in order to establish relationships between the characteristics of the material and its 76 physical-mechanical behaviour. The temperature of 800ºC was used as the test 77 temperature since at that temperature, the characteristics of a building mortar are 78 completely lost [27]. 79 3. MATERIALS AND METHODOLOGY 80 81 3.1 Starting materials 82 The following materials were used to manufacture the mortars: 83 - CEBASA CEM IV/B(V) 32.5N cement (recommended), in accordance with the 84 manufacturer's instructions (http://www.cebasa.com), for environments of certain 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 3 85 aggressiveness; this circumstance is interesting insofar as glass also provides 86 certain improvements in durability against aggressive chemical agents [23]. 87 - Standard sand provided by the Eduardo Torroja Institute (CEN Standard Sand 88 EN 196-1:2018) [28]. Particle size less than 2 mm and SiO2 content greater than 89 99% [29]. 90 - Granulated glass from domestic waste, mostly common containers; this material 91 was crushed in a jaw crusher and sieved to a particle size of less than 2 mm [19]. 92 The mixtures were kneaded according to a 1:3 dosage (cement:aggregate) following 93 the specifications of the UNE-EN 196-1 standard (Table 1) and maintaining the same 94 cement content, the same amount of water and the same maximum grain size and 95 particle size distribution. 96 Various proportions of ground glass were used to replace the aggregate (Figure 1). 97 The samples were designated as follows: RM (reference mortar), M10 (10% 98 substitution), M25 (25% substitution), M50 (50% substitution). The specimens 99 subjected to 800°C were called RMhT, M10hT, M25hT and M50hT, respectively. 100 101 102 103 104 105 106 Figure 1. Specimens with different crushed glass substitutes 107 108 109 110 Table 1. The dosage of components for each sample 111 CEMENT (gr) SAND (gr) GLASS (gr) WATER (cm3) RM M10 M25 M50 900 900 900 900 2700 2430 2025 1350 - 270 675 1350 600 600 600 600 112 113 3.2 Methodology 114 Samples were previously validated according to their docility to ensure their fluidity 115 complied with the workability requirements established in the UNE-EN 13395-1 116 standard [30]. 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 10 300 exothermic changes were due to modifications in the crystalline structure and chemical 301 reactions (loss of structural water, dehydration of portlandite and decarbonation of 302 calcite). 303 The DTA/TGA curves show three main endothermic peaks in the samples. The first 304 peak was observed between 70°C and 100°C, consistent with a significant loss of 305 mass in the TGA curve, which can be attributed to water loss and dehydration of 306 certain hydrated silicates. The second endothermic peak (≈440-460°C) corresponded 307 to the dehydration of portlandite, generating CaO. The third peak (≈765-785°C) was 308 produced by the decomposition of calcium carbonate and CO2 emission [42]. It is worth 309 noting the exothermic peak that was observed at ≈300ºC, associated with the 310 decomposition of organic matter. The increase in intensity with glass content was due 311 to organic matter residue fixed on the surface of household glass. In relation to the TG 312 diagram, three expected elements can be observed: the first one defined by water loss 313 around 100ºC; a slight drop due to the dehydroxylation of portlandite; and a final 314 decrease due to the decomposition of calcite (Figure 6). 315 316 Figure 6. DTA/TGA diagrams of the samples studied 317 318 4.5 Analysis of internal structures by SEM 319 The analysis of the internal structures of the mortars by SEM revealed correct internal 320 cohesion between the glass grains and the cement binder despite the regular fracture 321 planes presented by the glass, which could cause loss of adherence (Figure 7). This 322 circumstance allowed the authors to establish the hypothesis that decreases in 323 resistance observed at compression were not due to landslides in the planes of the 324 glass grains but to a lower resistance of aggregates. In fact, flexural tests showed an 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 11 325 increase in resistance for samples M10 and M25 with respect to RM, revealing a good 326 response to resistance of aggregate/paste interfaces. 327 328 329 Figure 7. Aggregate of glass adhered to the cement matrix. 330 331 Once the samples had been subjected to heating, the internal structures presented 332 significant alterations. Figure 8a shows the decomposition of the binder with evident 333 cracking of the cementitious matrix [43]. The glass grains showed an unaltered 334 structure with good fixation to the paste, without apparent loss of adherence (Figure 335 8b). 336 337 338 Figure 8. (a) Cracking of the conglomerate after being subjected to 800ºC (M10hT) 339 (b) Insertion of aggregate grains in the matrix (M10hT) 340 341 The heating process revealed an unexpected circumstance, namely the potent 342 formation of calcium silicate crystals. As indicated by Tan [44], starting at 200ºC, 343 calcium silicate surfaces become rough and the appearance of some small holes can 344 be observed. As the reaction proceeds with temperature, clean and well-defined 345 acicular crystals may begin to form (Figure 9) and disaggregation of the material occurs 346 [45-47], which is visible to the naked eye. Other authors describe this type of structure 347 formed by heating and attribute this to the formation of xonotlite (Ca6Si6O17(OH)2) [41]; 348 however, this mineral was not detected in the DRX. Calcite decomposition also causes 349 the appearance of geometrically well-defined calcium oxide crystals [48], which can 350 preferably be observed inside pores (Figure 10). 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 12 351 352 Figure 9. SEM micrographs of calcium silicates (M10hT). 353 354 355 356 Figure 10. SEM micrographs of calcium oxide crystals. 357 358 359 360 5. CONCLUSIONS 361 362 The incorporation of glass represents an obvious ecological alternative to natural 363 aggregates. As a substitute for aggregate in cement mortars, it reduces density, thus 364 helping to reduce the overall weight of the mortar and/or concrete construction 365 elements. 366 The resistance values presented statistically significant differences. However, 367 according to the results of this and other similar studies, it is not possible to conclude 368 that these materials display homogenous mechanical behaviour, since this is strongly 369 determined by the components, dosage and manufacturing process of the test pieces. 370 The statistical analysis of mortars resistance broadly revealed the incidence of the 371 incorporation of glass aggregate on the mechanical capacities of the conglomerate 372 evaluated. Based on a comparison of flexural resistance values obtained for the 373 reference mortar with the results obtained in the other specimens, it was concluded 374 that the improvement in resistance was not significant, with the exception of the 375 samples with a 25% replacement. However, despite their loss of resistance, samples 376 with replacement of natural aggregates subjected to heating at 800ºC showed a 377 significant improvement in resistance with respect to the reference sample. From 378 observations of the compression resistance values obtained for the reference mortar 379 and samples with crushed glass, it was concluded that the decrease in resistance was 380 significant, as for the specimens subjected to 800°C. No improvement was observed 381 between the reference mortar and the other samples, except for the specimens with a 382 10% replacement, but this was not significant. 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 13 383 The mortars with crushed glass aggregate showed a clear improvement in thermal 384 properties, displaying positive behaviour in relation to their thermal response and 385 insulation capacity. This behaviour was particularly influenced by thermal diffusivity. 386 Internal structure undergoes changes inherent to heating effects, as revealed by the 387 mineralogical analyses. However, it was not affected by the incorporation of crushed 388 glass. No faults were observed in the aggregate/paste interfaces in the samples tested 389 at room temperature, nor in the samples tested at 800ºC. 390 ACKNOWLEDGMENTS 391 392 The authors wish to express their gratitude to CITIUS at the University of Seville for the 393 use of the laboratories for the characterization analyses. 394 395 REFERENCES 396 397 [1] Y. Meng, T.Ch. Ling, K. Hung Mo, Recycling of wastes for value-added applications 398 in concrete blocks: An overview. Resources, Conserv. and Recy., 138 (2018) 298312. 399 https://doi.org/10.1016/j.resconrec.2018.07.029 400 [2] I.B. Topçu, M. Canbaz, Properties of concrete containing waste glass, Cem. Conc. 401 Res., 34 (2004) 267274. https://doi.org/10.1016/j.cemconres.2003.07.003 402 [3] D. Han, Y. Yang, C. Ying, Z. Sierens, H. Fan, J. Li, Efficient recycling and reuse of 403 waste concrete on a construction site, Int. Concrete Abstracts Portal, 326 (2018) 404 38.138.10. 405 [4] F. Valadares, M. Bravo, J. de Brito, Concrete with used tire rubber aggregates: 406 mechanical performance. ACI Mater. J. 109–M26 (2012) 283–292. 407 [5] Li J., M. Saberian, B. T. Nguyen, Effect of Crumb Rubber on Mechanical Properties 408 of Crushed Recycled Pavement Materials. Jour. Environmental Management 218 409 (2018) 291299. https://doi.org/10.1016/j.jenvman.2018.04.062 410 [6] M.N. Gaikwad, A. Gunjawate Shubham, Y. Hole Gannesh, M. Kadam Mangesh, A. 411 Ghorpade Pratik, Experimental study on plastic waste as a course aggregate for 412 structural concrete. Int. Jour. Recent and Innovation Trends in Computing and 413 Communication 6 (2018) 6367. 414 [7] C. Meyer, The greening of the concrete industry. Cement and Concrete Composites 415 31 (2013) 601605 https://doi.org/10.1016/j.cemconcomp.2008.12.010 416 [8] N. Karakaš, K. Strukar, T. Kalman Šipoš, I. Miličević, Potential use of recycled 417 aggregate in structural concrete elements. 9th International Congress of Croatian 418 Society of Mechanics (2018). 419 [9] C. Lobo, New perspective on concrete durability. Concrete InFocus, Spring (2007) 420 2430. 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 14 421 [10] D. Romero, Concrete durability and environmental performance of mixtures 422 containing recycled hazardous waste aggregates, PhD Thesis, University of Miami 423 (2013). 424 [11] R. Vandhiyan, K. Ramkumar, R. Ramya, Experimental Study on Replacement of 425 Cement by Glass Powder. Int. Jour. Engineering Research and Technology (IJERT) 426 Vol.2, 5 (2013). 427 [12] M. Saillio, F. Frohard, T. Chaussadent, L. Divet, A. Tagnit-Hamou, Durability of 428 concrete with alternative supplementary cementitious materials. 10th ACI/RILEM 429 International Conference on Cementitious Materials and Alternative Binders for 430 Sustainable Concrete (2017), p.19. 431 [13] E. L. Tucker, C. C. Ferraro, S. J. Laux, T. G. Townsend, Economic and life cycle 432 assessment of recycling municipal glass as a pozzolan in portland cement concrete 433 production. Resources, Conserv. and Recy., 129 (2018) 240–247. 434 https://doi.org/10.1016/j.resconrec.2017.10.025 435 [14] Y. Jani, W. Hogl, Waste glass in the production of cement concrete-A review. Jour. 436 Environmental Chem. Eng., 2 (2014) 17671775, 437 http://dx.doi.org/10.1016/j.jece.2014.03.016 438 [15] N. Roz-Ud-Din, S. Parviz, Strength durability of recycled aggregate concrete 439 containing milled glass as partial replacement for cement, Constr. Build. Mater., 29 440 (2012) 368377. https://doi.org/10.1016/j.conbuildmat.2011.10.061 441 [16] A. Shayan, A. Xu, Performance of glass powder as a pozzolanic material in 442 concrete: A field trial on concrete slabs, Cem. Conc. Res., 36 (2006) 457–468. 443 https://doi.org/10.1016/j.cemconres.2005.12.012 444 [17] K. Afshinnia P. R. Rangaraju, Impact of combined use of ground glass powder 445 crushed glass aggregate on selected properties of Portland cement concrete. Constr. 446 Build. Mater., 117 (2016) 263272, https://doi.org/10.1016/j.conbuildmat.2016.04.072 447 [18] M. J. Terro, Properties of concrete made with recycled crushed glass at elevated 448 temperatures, Building Environment, 41 (2006) 633–639. 449 https://doi.org/10.1016/j.buildenv.2005.02.018 450 [19] V. Flores-Alés, V. Jiménez-Bayarri, A. Pérez-Fargallo, Influencia de la 451 incorporación de vidrio triturado en las propiedades y el comportamiento a alta 452 temperatura de morteros de cemento, Bol. Soc. Esp. Cerámica y Vidrio (2018) 257-265 453 https://doi.org/10.1016/j.bsecv.2018.03.001 454 [20] S. M. H Shafaatian , J. R. Wright , F. Rajabipour, Performance of recycled soda– 455 lime glass powder in mitigating alkali–silica reaction. Green Materials (2018) 456 https://doi.org/10.1680/jgrma.18.00032 457 [21] K. Rashid, R. Hameed, H. A. Ahmad, A. Razzaq, M. Ahmad, A. Mahmood, 458 Analytical framework for value added utilization of glass waste in concrete: Mechanical 459 and environmental performance. Waste Management, 79 (2018) 312–323. 460 https://doi.org/10.1016/j.wasman.2018.07.052 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 15 461 [22] B.P. Seung, B. C. Lee, J. H. Kim. Studies on mechanical properties of concrete 462 containing waste glass aggregate. Cem. Conc. Res., 34 (2004) 2181–2189. 463 https://doi.org/10.1016/j.cemconres.2004.02.006 464 [23] D. Serpa, A. Santos Silva, D. Soares, M. B. Santos, J. de Brito, Behaviour of glass 465 in cement-based materials: its role on ASR, Material Science Forum, 730-732 (2012) 466 415–420. https://doi.org/10.4028/www.scientific.net/MSF.730-732.415 467 [24] A. S. Khalil, M. A. Mahmoud, A. AL-Hathal, M. K. Jawad, B. M. Mozahim, The 468 effect of replaced recycled glass on thermal conductivity and compression properties of 469 cement. Journal of Physics: Conference Series, 1003 (2018). 470 http://dx.doi.org/10.1088/1742-6596/1003/1/012127 471 [25] A. Al-Sibahy, R. Edwards, Mechanical and thermal properties of novel lightweight 472 concrete mixtures containing recycled glass and metakaolin. Constr. Build. Mater., 31 473 (2012) 157167, https://doi.org/10.1016/j.conbuildmat.2011.12.095 474 [26] R. R. Krishnamoorthy, J. A. Zujip, Thermal Conductivity and Microstructure of 475 Concrete Using Recycle Glass as a Fine Aggregate Replacement. International Journal 476 of Emerging Technology and Advanced Engineering, 3 (2013), 463471. 477 [27] Y. Pei, Sh. Li, F. Agostini, F. Skoczylas, Effects of severe heating and rehydration 478 on poro-mechanical properties of a mortar, Cem. Conc. Res., 115 (2019) 460-471 479 https://doi.org/10.1016/j.cemconres.2018.09.020 480 [28] UNE-EN 196-1:2018 Métodos de ensayo de cementos. Parte 1: Determinación 481 de resistencias. 482 [29] UNE-EN 1936:2007 Métodos de ensayo para piedra natural. Determinación de la 483 densidad real y aparente y de la porosidad abierta y total. 484 [30] UNE-EN 13395-1:2002 Productos y sistemas para la protección y reparación de 485 estructuras de hormigón. Métodos de ensayo. Determinación de la trabajabilidad. 486 Parte 1: Ensayo de escurrimiento de los morteros tixotrópicos. 487 [31] E.T.Stepkowska, J.M. Blanes, F. Franco, C. Real, J.L. Pérez-Rodriguez, Phase 488 transformation on heating of an aged cement paste. Thermochimica Acta, 420(2004) 489 79-87 https://doi.org/10.1016/j.tca.2003.11.057 490 [32] M. Heikal, Effect of temperature on the structure and strength properties of cement 491 pastes containing fly ash alone or in combination with limestone. Ceramics Silikaty, 492 50(2006) 167-177 493 [33] R.E. Walpole, R. H. Myers, Sh. L. Myers, K. Ye, Probability and statistics for 494 engineers and scientists (9th Ed.) Pearson (2012) 246-250. 495 [34] A. Nieves, F. Domínguez, F. Flores, A. Gutiérrez, Probabilidad y estadística para 496 ingeniería (1ª Ed) México: McGrawHill (2010) 380-387. 497 [35] J. Blumm, A. Lindeman, B. Niedrig, Measurement of the thermophysical properties 498 of an NPL thermal conductivity stard Inconel 600, High Temp. Press., 35/36, 621-626. 499 https://doi.org/10.1068/htjr145 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 16 500 [36] F. Kontoleontosa , P. Tsakiridisb, A. Marinosa , N. Katsiotisa , V. Kaloidasc , M. 501 Katsioti dry-grinded ultrafine cements hydration. physicochemical and microstructural 502 characterization, Materials Research 16(2013) 404-416 https://doi.org/10.1590/S1516- 503 14392013005000014. 504 [37] M. A. Tantawy, Effect of high temperatures on the microstructure of cement paste. 505 Jour. Mat. Sci. and Chem. Eng., 5 (2017) 33-48 506 https://doi.org/10.4236/msce.2017.511004 507 508 [38] G.F. Peng, Z.S. Huang, Change in microstructure of hardened cement paste 509 subjected to elevated temperatures. Constr. Build. Mater., 22(2008) 593-599 510 [39] A. Mohajerani, J. Vajna, T.H.H. Cheung, H. Kurmus, A. Arulrajah, S. Horpibulsuk, 511 Practical recycling applications of crushed waste glass in construction materials: A 512 review, Constr. Build. Mater., 156 (2017), 443-467. 513 https://doi.org/10.1016/j.conbuildmat.2017.09.005 514 [40] M. Batayneh, M. Iqbal, A. Ibrahim, Use of selected waste materials in concrete 515 mixes. Waste Manage., 27 (2007), 1870-1876. 516 https://doi.org/10.1016/j.wasman.2006.07.026 517 [41] M. Adaway, W. Ying, Recycled glass as a partial replacement for fine aggregate in 518 structural concrete-Effects on compressive strength. Electronic Jour. Struct. Eng., 14 519 (2015), 116-122. 520 [42] M. Aly, M.S.J. Hashmi, A.G. Olabi, M. Messeiry, A.I. Hussainc, Effect of nano clay 521 particles on mechanical, thermal and physical behaviours of waste-glass cement 522 mortars. Materials Science and Engineering A 528 (2011) 7991–7998 523 doi:10.1016/j.msea.2011.07.058 524 [43] J. Wang, L. Yuan, N. Wang, W. Jiang, Z. He Experimental study on mechanical 525 performance of lightweight aggregate concrete after high temperature heating.J Nat 526 Disasters, 23 (2014) 258-263 527 528 [44] W. Tan, G. Zhu, Y. Liu, et al. Effects and mechanism research of the crystalline 529 state for the semi-crystalline calcium silicate Cem. Concr. Res., 72 (2015) 69–75. 530 https://doi.org/10.1016/j.cemconres.2015.02.020 531 [45] T.V. Vakalova, V.M. Pogrebenkov, N.P. Karionova, Solid–phase synthesis of 532 wollastonite in natural and technogenic siliceous stock mixtures with varying levels of 533 calcium carbonate component. Ceramics International 42 (2016) 16453–16462. 534 https://doi.org/10.1016/j.ceramint.2016.06.060 535 [46] J. Zou, C. Guo, Y. Jiang, C. Wei, F. Li, Structure, morphology and mechanism 536 research on synthesizing xonotlite fiber from acid-extracting residues of coal fly ash 537 and carbide slag. Materials Chemistry and Physics. 172 (2016) 121–128. 538 https://doi.org/10.1016/j.matchemphys.2016.01.050 539 540 [47] G. Wang, C. Zhang, B. Zhang, Q. Li, Z. Shui, Study on the high-temperature 541 behaviour and rehydration characteristics of hardened cement paste, Fire 542 Mater, 39 (2015) 741–750. https://doi.org/10.1002/fam.2269 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 17 543 544 [48] M.I. Romero-Hermida, A.M. Borrero-López, F.J. Alejandre, V. Flores-Alés, A. 545 Santos, J.M. Franco, L. Esquivias, Phosphogypsum waste lime as a promising 546 substitute of commercial limes: A rheological approach, Cem. & Conc. Composites, 95 547 (2019) 205-216. https://doi.org/10.1016/ j.cemconcomp.2018.11.007 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 Table 1. The dosage of components for each sample Cement (gr) Sand (gr) Glass (gr) Water (cm3) RM M10 M25 M50 900 900 900 900 2700 2430 2025 1350 - 270 675 1350 600 600 600 600 Table 2 Chemical composition of major components of cement and glass expressed in terms of percentage (%). SiO2 Al2O3 Fe2O3 MnO MgO CaO Na2O K2O TiO2 P2O5 SO3 PC Cement 29.36 15.83 2.97 0.05 1.37 43.22 0.18 0.81 0.80 0.81 2.36 4.85 Glass 71.05 1.50 0.19 - 0.76 11.38 13.19 0.72 - - - 0.10 Table 3. Descriptive data of flexural strengths (AV: average value, SD: standard deviation and VC: variation coefficient) RM M10 M25 M50 RMHT M10HT M25HT M50HT AV 3.095 3.3340 3.5450 2.9560 0.0325 0.4780 0.5740 0.5000 SD 0.20662 0.17587 0.06758 0.19282 0.02500 0.10616 0.010784 0.06218 VC 0.0668 0.0528 0.0191 0.0652 0.7692 0.2221 0.1879 0.1244