EFFECT OF USING RECYCLED WASTE CONCRETE MATERIALS ON RUTTING BEHAVIOR OF HMA

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 4, April 218, pp , Article ID: IJCIET_9_4_78 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed EFFECT OF USING RECYCLED WASTE CONCRETE MATERIALS ON RUTTING BEHAVIOR OF HMA Dr. Mohammed A. Mahmoud Asst. Professor, Building and Construction Engineering Department, University of Technology, Baghdad-Iraq Dr. Ammar A. Shubber Lecture, Building and Construction Engineering Department, University of Technology, Baghdad-Iraq Aqeel Raheem Jabur Chief Eng in civil Engineering Department, College of Engineering Al-Mustansiriya University, Baghdad- Iraq ABSTRACT Demolishing and construction waste materials create from buildings debris cause an environmental and economical problems in developing countries. The current study represents a practical research about feasibility of utilizing recycled concrete aggregate(rca) in the binder course of hot mix asphalt (HMA) as a partial substitute of coarse and fine aggregate. The engineering properties of HMA mixtures containing RCA have been assessed for changing the percentages of binders based on the superpave mix design method. In this study local available materials after recycle are used including penetration grade of asphalt binder of (4-5), aggregate gradation a maximum sizes of (19 mm) and filler (cement). Atotal (16) sample containing RCA with nine different percentages (,1, 2, 3, 4, 5, 6, 7 and 8 )% from the weight of total mix were mixed with pure crushed aggregates and compacted using superpave mix design method to produce HMA specimen to find the optimum asphalt content for these ratios. A (32) asphalt concrete slab sample for rutting test has been prepared by Wheel Roller Compactor (WRC) and tested at two levels of temperatures (4-6)ºc. After determining the Optimal asphalt content (OPT) for ratio used, rutting performance is evaluated using Wheel Tracking test. The results showed that recycled aggregates enhanced rutting resistance (especially for mixture with 5% RCA) at the higher temperatures. Finally, the models of rut depth analysis were simulated statically by (SPSS) version 22, where the selection of better models based on the equation coefficient of determination (R 2 ) equal to (76%) of the rut dupth. Key words: Recycled Concrete Aggregate, Hot Mix Asphalt, Depth Rut editor@iaeme.com

2 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur Cite this Article: Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur, Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA, International Journal of Civil Engineering and Technology, 9(4), 218, pp INTRODUCTION Recycled concrete aggregate (RCA) is considered from major waste in the countries. Ergo the reason, it was suggested that disposal the debris from demolished building in such a way as to get recycled concrete aggregate (RCA) to be recycled in flexible pavement. The use of recycled concrete aggregates a whole new range of potentials in the use for again for materials in the roads and buildings structure. The RCA is a best solutions to disposal from wastes. The deliberating to utilize of RCA has began before more than fifty years. Recycle concrete aggregate (RCA) can be useful in several different ways. It can be used as an aggregate in new concrete or asphalt. Economic and environmental Advantages have encouraged to use again recycled materials in new constructions (Huang, and Heidrich, 27). In view of the fact that amount of aggregate in asphalt pavement mixtures is approximately (9 to 95) % by weight or (75 to 85) % by volume, about 125 tons of aggregates are being used up for each (km) of flexible pavements (Zoorob and Suparma, 2). Initially, Germany was the first country using the demolition waste, after the end of world war II (Khalaf et al., 24). In studying the use of RCA in HMA, it is pertinent to understand key aspects of its interaction with asphalt such as its absorptive behavior under dynamic loading conditions (Beale and You, 21). The Federal Highway Administration (FHWA report in 213) included a comprehensive up to date literature review on the properties of recycled concrete aggregate over the world. Some necessary information is extracted as mentioned by FHWA, (213) which related to this study. The results of the researches indicated that, the addition of RCA to the Pure asphalt mixtures results in stiffer mixes lead to the better rutting resistance (Shen, 24) and (Gul, 28). There are two basic kinds of Rutting: the first Asphalt mixture rutting and the second subbase or subgrade rutting. Asphalt mixture rutting is being bring forth lower pavement layer, Because of the pavement surface which exhibits wheel path depressions as a result of unadequate (little) mix design and compaction. Granular material in the subgrade rutting bring forth when the layers exhibit wheel path depressions because of the high loading. (NABIL, 26). The resilient modulus, and creep values were lesser for the RCa HMA than for a mix designed wholly with conventional pureaggregates. (Paranavithana and Mohajerani, 26). Akbulut and Gurer, the researches done in some countries has look asufficient ability to develop utilize of the builds waste as a basic in new use. Millions tons of construction and demolition (D&C) the waste generated daily from: Destruction of structures & buildings from the wars and earthquakes. Demolishing of old constructs such buildings for bridges, and the concrete dams and construction activities, useless. Waste concrete product due to testing of concrete cylinder and cube (destructive testing) in the laboratories. Demolition and Construction (D&C) waste from the rehabilitation pavement, or concrete in buildings editor@iaeme.com

3 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA 2. THE SCOPE OF WORK To complete the necessary aim of this study, the following missions will be do for hot recycled concrete mixtures: Utilizing the Superpave to design the recycled concrete mixtures, and showed the variables between them with many differences such as -pure aggregate with RCA gradation, bulk densit (Gb), air voids (av), VMA, VfA, dust proportion(dp), curing and compaction. Determining the Optimum Asphalt Content (OAC) of RCA in hot asphalt mixtures enclosing RCA, based on the superpave design method. Assessing permanent deformation (rutting) using wheel tracking test (WTT). Knowledge of the location history along with investigative results for determining what kind of disposal is required and if there is pollution, the condition of the waste concrete is not suitable for recycling, will have to be disposed of it as solid or dangerous waste. 3.EXPERIMENTAL WORK Experimental works was carry out in: Laboratories the in Building and Construction Department-- University of Technology. The Engineering Department-University of Al-Mustansiriya Highway Department Laboratories of the National Center for Construction Laboratories. Researches (NCCLR) in Baghdad) and Directorate of Materials Researches. 4. MATERIALS USED The materials used in this study are divided into two categories: Pure materials include: Asphalt Cement, Aggregate and Filler. Recycled Concrete Aggregate (RCA). 5. PURE MATERIALS 5.1. Asphalt cement Asphalt cement (AC) of (4-5) was used as to the suggestion of standard Performance Grade of the Al- Daurah binder which usually used in Baghdad Coarse and fine aggregates The crushed quartz aggregates brought up from graded aggregate stockpiles are utilized for a regionally asphalt concrete batch plant which is located in eastern south of Baghdad (Jurf Al- Naddaf) 5.3. Filler The filler utilized in this work is Ordinary Portland cement from Al- Mass Company Recycled concrete aggregate RCA was brought up from Bab-Al Maadam Region, near Al-Mustansiriya University, Faculty of Engineering. The age of these buildings are more than 3 year, as show in Plate (1).Eight percentages of RCA are used in preparates of specimens of laboratory testing (1,2,3,4,5,6,7 and 8%) instead of pure aggregate editor@iaeme.com

4 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur Plate (1) Recycled concrete aggregate 6. DESIGN SELECTION OF AGGREGATE STRUCTURE A superpave criterion was used to design three (and sometimes more) trial blends types of asphalt mixtures that evaluated to select the design of aggregate structure. Trial blending consists of varying stockpile percentages of each aggregate to obtain blend gradations meeting the graduation requirements for the particular mixture. Table (1) and Figure (1) demonstrate the trial blends for Mixture Design. The power of.45 gradation chart is used to define a permissible gradation. The maximum density gradation which is theoretically plotted as a straight line from the maximum aggregate size to the origin. The (vertical-axis) of chart percent passing of aggregate and (horizontal-axis ) is an arithmetic scale of sieve size in mm, raised to the.45 power as ((4.75 mm ) sieve is plotted at (2.2 mm )). Superpave is used accordance with standard set of AASHTO M323 (212) sieves and the following definitions with respect to aggregate size are used: *Maximum Size: One sieve size larger than the nominal maximum size. *Nominal Maximum Size: One sieve size larger than the first sieve to retain more than ten percent. They are placed on the nominal maximum size, an intermediate size (2.36 mm), and the dust size (.75 mm). 7 editor@iaeme.com

5 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA Table (1) Trial Blends for Mixture Design with the Limitations. Table three blend gradation Standard sieve size (mm) filler Iraqi specification R9, Binder Min Max superpave specification AASHTO M323 (212) Control Point Restricted Zone Blend Gradation passing% 3 Blend Blend Weight of aggregate for sample 45 gm Blend Blend Blend Figure (1) Trial Blends for Mixture Design. Table (2) Properties of Mixture Compaction for Asphalt Binder Content Asphalt Content % G mm No. of Gyrations Height mm W Mix. gm G mb Estimated 2.49 Correction Factor G mb Corrected N Ini.= N Des.= N Max.= N Ini.= N Des.= N Max.= N Ini.= N Des.= N Max.= N Ini.= N Des.= N Max.= editor@iaeme.com

6 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur 7. OPTIMUM ASPHALT BINDER CONTENT SELECTION For Blend 1 the optimum asphalt content of (4.9%) is determined at 4 % air-voids level. The results of the void analysis and mix properties for Superpave mixes are displayed in the Tables (2), (3) and Figure (2). Table (3) Volumetric Test Results at N design Asphalt Gmm@Nintial Va% VMA% VFA% content % Gmm@Nmaxim% Dust/Binder Criteria 4. Min Less than 89 Less than Figure (2) Relationship between the Volumetric Properties Superpave Mix design: (A) Air Voids % (B)Void mineral aggregate( VMA)% (C) Void Filler aggregate(vfa)% Table (4) shows the summary of adding recycled concrete aggregate with different percentages on properties of asphalt mixture. According to Superpave mix design criteria, all the percentages are compatible with superpave criteria, except 8% of RCA because this percentages has less than Specified minimum values for (VMA) at the design (AV) content of 4% which a function of nominal maximum aggregate(19mm) size. Figures (4) to (5) show the values of optimum asphalt, Void Filler aggregate and Void Filler aggregate respectively with adding of recycled concrete aggregate to mixture. lt can be seen that the optimum asphalt of waste concrete aggregate is much higher compared with that of pure crushed aggregates and increased with increasing of RCA content in the mixtures due to higher porosity of waste concrete and higher attached mortars on the surface of the crushed concretes. RAC % Control mix 1 % 2 % 3 % 4 % 5 % 6 % 7 % 8 % Table (4) Summary the results of added RCA For each ratio used OPT % Criteria VFA % VMA % Min 13. Gmm@Ninitial % Less than 89 Gmm@Nmaxm % Less than 98 Dust/Binder editor@iaeme.com

7 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA Figure (3) Effect of recycled concrete aggregate with optimum Asphalt Figure (4) Effect of recycled concrete aggregate with Void Filler aggregate Figure (5) Effect of recycled concrete aggregate with Void mineral aggregate 8. PERMANENT DEFORMATION TEST The RCA mixture must be assessed for rutting resistance capacity to avert possible permanent deformation of the pavement structure Preparation of Slab Specimens In order to evaluate the RCA mixtures against permanent deformation characteristics, the compacted asphaltic slab samples are prepared. In this study, the compacted asphaltic slabs are prepared at air voids equal to (4%) using Roller Compactor Device according to (EN Part 33:23) and Superpave system (AASHTO Designation: T ). The sample for utilized has dimensions of (6mm) in height, (3) mm in width and (4) mm in length. As Steel rectangular mold of (4) mm in length, (12) mm in height and (3) mm, in width (at NCCL) is used (Plate 3-7A). The HMA is short term aged on incinerator for (4 hrs) at the temperature of (135) C for compaction approval to (Asphalt institute (1994)). Aging process same as that take place in field between mixing and placement and permits for this aging represents the aging that occurs in the field between mixing and placement and allows for absorption of the asphalt binder into the aggregate pores. The slab mold and spatula are heated in incinerator at the same compaction temperature to make sure that the temperature of mix is 73 editor@iaeme.com

8 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur not reduced. A chunk of non-absorbent paper, cut to size, is put in the down and to a sides of mold before putting the mixture The asphalt mixture is put in the hot mold and another chunk of non-absorbent paper is cut to size and put on the up of the mix, then the mold put on the compaction device the sample is compacted under fixed load of (7.) kn load, passes through the monitoring arm (arm convex) on the form many times to obtain the density proportion and the required height Wheel Tracking Machine and Rut Depth Test The Pavement Wheel Tracker is equipment for testing the workability of asphalt mixes by simulating roadway conditions. The test provides information about the rate of permanent deformation (rut) from a moving, concentrated load. The Wheel tracking machine (NCCL in Baghdad) is used for rut depth test of asphalt slab specimen. The wheel tracking apparatus shown in Plate (2) consists of a loaded wheel, which bears on a sample held on a moving table. The table reciprocates with simple harmonic motion through a distance of 23 ± 1 mm with a frequency of (27) load cycles passes per minute. The wheel is fitted with a solid rubber tire of outside diameter between (2mm) and (25 mm). The wheel load under standard conditions is (7 ± 1 N) and passes repetitively over the sample for up to 1, cycles. If the maximum allowed deformation is reached before 1, cycles, the wheel will lift off the failed sample,). A Linear variable differential transformer (LVDT s) is used to measure the deformation of the sample. The test device in approximately 1, load cycles, as specified by the (AASHTO T 34-1) and the European Standard (BS Part 22: 23). It is implemented in this work of two temperatures (4º C and 6º C) for the permanent deformation testing Specimen Testing Steps of specimen testing: Start Switch on the Wheel tracker unit by means of the mains switch, After little seconds the display will show the main menu and the unit is ready to be operated, Samples are heated at test temperature of 6 C in an external oven in accordance with EN :23. Loading the specimen on the mold and confining it with the appropriated confining frame; the confining frame should be properly secured to the moving carriage with the relevant retainers; also it is necessary to make sure that the rubber wheel act in the centre of the sample itself. Press on operation key, after that the arm of wheel lower on surface of slab and begin to be moving at a constant rate. Disengaging and move the holder of the displacement transducer and adjust its reference plate in order the transducer probe is compressed approximately 75% of its total travel. This allowed having sufficient travel available to measure the track formation on the sample. When the end of the test, the arm of wheel will return automatically to its upper position while the display will show the results of the test show and the parameters. Switch off the Wheel tracker unit by means of the mains switch an 74 editor@iaeme.com

9 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA Plate (2) Wheel tracking machine 9. EXPERIMENTAL WORK RESULTS & ANALYSIS The recycled concrete aggregate (RCA) mixture should be evaluated for rutting resistance ability to avoid a possibility permanent deformation (rutting) of the gross pavement structure. In recent years, the possibility for rutting on the highways in Iraq has increased due to the higher traffic volumes [equivalent single axle loads (ESALs)] and the increased use of radial tires, which normally higher Puffy pressures. The Wheel tracking (WT) device in the (NCCL) is utilized to determine for Rut Depth of specimen (asphalt slab) according to (BS EN :23). The failure criteria for all testing samples continuing for 1 load cycles or until the rut depth of 25 mm is reached. Wheel tracking slabs are employed testing to evaluate rutting resistance of two different level of temperature of (4ᵒc & 6ᵒc), which mimic the effect of traffic. The results from Wheel track test in term of rut depth (mm) was obtained at different temperatures, Figures (6) show the relation between the number of 1,5 and1 cycles and the RCA content respectively at the 4ᵒc, while Figures (7) show the relation between the number of 1,5 and1 cycles and the RCA content respectively at the 6ᵒc. It can be observed from the results, that when the number of load cycles increases the rutting values are increased. All of the tested materials are presented load cycle 1 values less than 2 mm. Plastic flow (binder and aggregates are gradually moved without a volume change) is not occurred, therefore all specimens are not failed during the tests. This deportment can be ascribable to the existence of large ratios of un hydrated Portland cement particles that, when activated, increasing the shearing strength (friction and cohesion) of the hot asphalt concrete (recycled) mix and so the increasing in the rutting resistance (improvement in rutting) of this mixture. Figure (6) Rutting for temperature of 4ᵒC, (1, 5, 1) cycle editor@iaeme.com

10 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur Figure (7) Rutting for temperature of 6ᵒC, (1, 5, 1) cycle. Figure (8) refers to relationship between the rut depth & number of cycles of wheel load track at 4 ᵒc. It can be seen that the rut depth is increases with increasing of RCA content. Rut depth increased by (5.5%), (8%), (1.5%), (16%), (141.2%), (22%) and (244.7%) when the RCA is increased from the control mix (% RCA) to (1, 2, 3, 4, 5, 6 and 7 %) respectively. All ratios used are not failed in spite of increasing are satisfied the specifications of (BS EN ). Figure (8) Rut depth &Number of cycle wheel load track 4 ᵒc. Figure (9) depicts the relationship between rut depth and number of cycles using of wheel load track at 6 ᵒc. It can be seen that the rut depth decreases with increasing. RCA content. Rut depth was decreased by (4.9%), (15.2%), (23.9%), (31.4%), (49.7%), (33.3%) and (35.7%) when the RCA is increased from the control mix (% RCA) to (1, 2, 3, 4, 5, 6 and 7 %) respectively editor@iaeme.com

11 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA Figure (9) Rut depth & Number of cycle wheel load track 6ᵒc. Table (5) shows the mean values of plastic parameters. As shown in Figures (1) and (11), the plastic parameters results show that the rut depth (RD) and wheel-tracking slope in air (WTS)air for the test specimens at temperature (4 c) increases gradually with an increase in the recycled concrete ( RCA ) percent. This indicates that the addition of RCA to the mixture reduces the resistance to permanent deformation in contrast to the control mix (% RCA). For HMA containing of 5% RCA, the (WTS)air was similar to that of the control mixture. On the other hand, rut depth and wheel tracking slop in air are relatively decreased for the specimens at temperature (6 c ) with increase in of recycled material (RCA ) percentage compared with the control mix (% RCA). For HMA containing of 5% RCA, the (WTS)äir and (RD) decrease sharply compared with control mixture which mean a good resistance rutting is Achieved low rut depth and wheel-tracking slope in air of any mix give a higher resistance to permanent deformation. It can be concluded that (RCA) has a higher effect on reducing rut depth and wheel-tracking slope in air of asphalt mixtures at higher temperatures in contrast to the control mix. After testing, the visual condition of the sample and the amount of deformation indicated the mixture strength to rutting. Generally, pooring in mixtures performing leads to the high deformation and vice versa (See Plate 2). Table (5) Mean values of plastic parameters in conditional test Recycle concrete aggregate ( % ) Variable Temp ᵒc Rut depth (mm) Wheel- Tracking Slop in air(wts)a ir mm/1 3 Cycle % of increasing 6ᵒc % of decreasing 4ᵒc % of increasing 6ᵒc % of decreasing editor@iaeme.com

12 Dr. Mohammed A. Mahmoud, Dr. Ammar A. Shubber and Aqeel Raheem Jabur Figure (1) Mean rutting depth (mm) at temperature of (4& 6) ᵒc. Figure (11) Mean wheel-tracking slop for temperature of (4& 6) ᵒc. 1. CONCLUSIONS 1. Increasing the Optimum Asphalt Binder Content of RCA samples in proportion of ( 8.1, 18.3, 24.5, 34.7, 42.8, 46.9, 51 and 59.2%) in contrast to control sample respectively, when percentage of RCA increased (1, 2, 3, 4, 5, 6,7 and 8%) respectively. All percentages are compatible with superpave Criteria, except 8% of recycle concrete 2. The rut depth is increased in RCA samples in proportion of ( 5.5, 8,1.5, 16, 141, 22 and 244.7%) in contrast to control sample respectively, when RCA increased to (1,2,3,4,5,6 and 7%) at temperature (4 ᵒC) respectively, while a decrease in the rut depth of RCA samples in proportion of (4.9, 15.2, 23.9, 31.4, 49.7, 33.3 and 35.7%) is developed in contrast to control sample respectively, when RCA is increased to (1,2,3,4,5,6 and 7%) at temperature (6ᵒC) respectively. 3. The Wheel tracking slop in air is increased in RCA samples in proportion of ( 3, 4,5, 7, 12 and 21%) in contrast to control sample respectively, when RCA increased to (1,2,3,4,6 and 7%) at temperature (4 ᵒC) respectively, except for RCA (5%) as it is no different from the control mix while a decrease in the rut depth of RCA samples in proportion of (2.7, 4.1, 27.7, 29.1,66.6, 31.9,and 33.3%) is developed in contrast to control sample respectively, when RCA is increased to (1,2,3,4,5, 6 and 7%) at temperature (6ᵒC) respectively. 4. model were developed to predict a rut depth for the modified and local asphalt concrete by using SPSS version 22 are very simple to use within the range of data are used to find these models. There are a considerable saving in effort, (with in the data used) the following. RD.2 =.7RC+.166T-.153AC editor@iaeme.com

13 Effect of Using Recycled Waste Concrete Materials On Rutting Behavior of HMA Where RD: Rut depth (mm). AC: Asphalt content. T: Temperature (⁰C). RC: Recycle concrete 11. RECOMMENDATIONS AND SUGGESTIONS This work can be further extended with other different waste materials such as steel fiber, crashed stone and plastic. 1. It is suggested to immerse and wash the RCA materials before utilizing them in the HMA to decrease the excessive attached cements on the surface of the crushed aggregates and improve adhesion between materials in asphalt mixtures and RCA. 2. Future studies might try to use fine or coarse recycled concrete aggregates only in the HMA by superpave method. 3. Evaluating the field performance of superpave asphalt concrete by a trying section construction utilize local materials under traffic loading and prevailing environmental conditions. REFERENCES [1] AASHTO Designation, T321-3, (21), Determining the Fatigue Life of Compacted Hot- Mix Asphalt (HMA) Subjected to Repeated Flexural Bending. [2] AASHTO, (212), AASHTO M323, Standard Specification for Superpave Volumetric Mix Design, American Association of State Highway and Transportation Officials, Washington, D. C., USA. [3] AASHTO, (21), AASHTO R35, Standard Practice for Superpave Volumetric Design for Hot Mix Asphalt (HMA), American Association of State Highway and Transportation Officials, Washington, D. C., USA. [4] Akbulut, H, and C. Gurer, (27), " Use of aggregates produced from marble quarry waste in asphalt pavements ", Building and Environment, vol. 42, no. 5, pp [5] Asphalt Institute, (1994), Superpave Asphalt Mixture Design and Analysis, FHWA, Washington, DC. [6] FHWA, (213), "Using Recycled Concrete as Aggregate in Concrete Pavements to Reduce Materials Cost", Technical Report FHWA/IN/JTRP 213/18, U.S. Department of Transportation, Federal Highways Administration, Washington, DC. [7] Gul Waqar Ahmed, (28), " Effect of Recycled cement concrete content on rutting behaviour of asphalt concrete ", Doctoral Thesis. Middle East Technical University. Ankara;. [8] Huang,Y. R. N. Bird, and O. Heidrich, (27), A review of the use of recycled solid waste materials in asphalt pavements," Resources, Conservation and Recycling, vol. 52, no. 1, pp [9] Khalaf FM, DeVenny AlanS, (24), " Recycling of demolished masonry rubble as coarse aggregate in Concrete ", review. ASCE J Mater Civil Eng: [1] Paranavithana S, and Mohajerani A., (26), "Effects of recycled concrete aggregates on properties of asphalt concrete," Resour Conserv Recycl, 48. [11] Shen D.,DuJ., (24)," Evaluation of building materials recycling on HMA permanent deformation "constr Build mater;18: [12] Zoorob, S. E and L. B. Suparma, (2), " Laboratory design and investigation of the properties of continuously graded Asphaltic concrete containing recycled plastics aggregate replacement (Plastiphalt)," Cement and Concrete Composites, vol. 22, no. 4,pp editor@iaeme.com