International Journal of Engineering Advanced Research (IJEAR) eISSN: 2710-7167 [Vol. 1 No. 4 December 2020]
Journal website: http://myjms.mohe.gov.my/index.php/ijear
UTILIZATION OF WASTE MATERIALS IN THE
PRODUCTION OF INTERLOCKING COMPRESSED EARTH BRICK
Hidayati Asrah1*, Haikal Khamidy Abdul Hamid2, Serzamin Khan3, Abdul Karim Mirasa4 and Lillian Gungat5
1 3 4 5 Faculty of Engineering, Universiti Malaysia Sabah, Kota Kinabalu, MALAYSIA
2 Maju Integrated Engineers Sdn Bhd, Kuala Lumpur, MALAYSIA
3 Faculty of Engineering and Information Sciences, University of Wollongong, New South Wales, AUSTRALIA
*Corresponding author: [email protected]
Article Information:
Article history:
Received date : 22 October 2020 Revised date : 18 November 2020 Accepted date : 30 November 2020 Published date : 7 December 2020
To cite this document:
Asrah, H., Abdul Hamid, H., Khan, S., Mirasa, A., & Gungat, L. (2020).
UTILIZATION OF WASTE
MATERIALS IN THE PRODUCTION OF INTERLOCKING COMPRESSED EARTH BRICK. International Journal Of Engineering Advanced Research, 1(4), 27-40.
Abstract: Waste rubber tires (WRT) and water treatment sludge (WTS) can be economical and sustainable alternative materials for the interlocking compressed brick (ICEB) production. Utilization of these wastes to produce green ICEB brick represent a mean of reducing the waste disposal problem and consecutively helps in reduction of resources depletion and environmental degradation. This research sought to investigate the feasibility of the WRT and WTS to be used in the ICEB production as partial clay soil and sand replacement, respectively with the aim of showing that both wastes can be put into use in construction today. The amount of replacement was 5%, 10% and 15% for WRT and 10%, 30% and 50% for WTS.
The performance of the green ICEBs was evaluated by the compressive strength and water absorption based on the standard requirement of BS3921:1985. The effect of wastes on the density of the green ICEBs was also
1. Introduction
In Malaysia, a high number of waste rubber tyres are added annually to the existing volume, causing major challenges in terms of their disposal. Million scraps tyres are generated every year and added to the existing bulk which are currently stockpiled and dumped in the open spaces in the country. The number of motorcar waste tyres generated annually in the country was estimated to be 8.2 million or approximately 57,391 tonnes. About 60% of the waste tyres were disposed via unknown routes (Sandra Kumar, 2006). Most important issues with disposal of worn tyres as waste are its long disintegration time, its shape which is capable of infestation by parasites and insects, fire hazards, resurfacing of covered tyres (Kemkar, 2000).
On the other hand, growing industry of the water treatment plant also causes an increase of sludge generated from the water treatment plant. In Sabah, it was estimated that about 825 tonnes of sludge is produced from the water treatment plants (Haikal, 2019). The common practice of WTS disposal in Malaysia is either discharged into the waterways or disposed to landfills (Ooi et al., 2018). However, the landfill disposal method is considered as impractical because of the depletion of landfill capacity and the high cost of transportation (Srinivasan et al., 2016). In addition, dumping the sludge back to the river and sanitary landfills are considered as unsustainable due to the high amount of heavy metal concentration in the sludge that may harm the aquatic organism in the river.
In order to reduce the amount of wastes produced, one of the popular trends is to incorporate wastes into the construction materials. By utilizing these wastes into construction materials, the negative effect of their disposal can be reduced. WRT has been used in a number of civil engineering application such as subgrade insulation for roads, subgrade fill and embankment backfill for walls and bridge abutments, landfill (Oikonomou & Mavridou, 2009), road construction (Bano &
Ahmad, 2019), and in concrete (Ayesha et al., 2019; Yang et al., 2019). Meanwhile, the WTS has been used in degraded soil (Abbas et al., 2020; Yue et al., 2020), as raw materials in the production of cement (Cong et al., 2020), ceramics (Benlalla et al., 2015), soil-cement (Melik, Habib, &
Mohamed, 2019) and mortars (Mundo et al., 2020). There were also researches to use wastewater sludge to develop brick (Tantawy and Mohamed, 2017). Another alternative is to use sludge as sand substitution in concrete (Lulu et al., 2020). Nowadays, the demand for sand has increased due WTS can be used to produce sustainable building materials for the housing project.
Keywords: interlocking compressed earth brick, waste rubber tires, water treatment sludge, compressive strength, water absorption, density.
Regardless of the various applications of WRT and WTS in construction, it was noticed that their use as raw materials in the interlocking compressed earth brick (ICEB) is very limited. The ICEB is a type of brick which has positive and negative frogs on the top and bottom of the brick, which disallows the horizontal movement (Malvika, 2017) (Fig.1). It was introduced as an alternative to conventional masonry bricks in wall panels for low rise building (Lee, Shek, & Mohammad, 2017).
The production of the ICEB does not require high skilled workers because the process is simple and convenient. It only requires three (3) stages process, which starts from the soil preparation, mix compression and curing.
Since the knowledge on the feasibility of both waste rubber tyre and water treatment sludge as raw materials in the ICEB production is very limited, this research aimed to investigate the possibility of using water treatment sludge and waste rubber tyre in interlocking compressed earth brick as partial sand and clay soil replacement, respectively to produce the green ICEB. So far, there is no specific standard requirement for the ICEB used as masonry in construction. In that case, most researchers are referring to the existing standard of masonry clay brick to assist them in evaluating the performance of ICEB in construction. The most important criteria are the compressive strength and water absorption. For this research, the ICEB was evaluated based on the British Standard (BS3921:1985), which states that the brick should have a minimum of 5 MPa compressive strength. Brick with water absorption 4.5% and 7% are categorized as Engineering A and B, and a damp-proof course 1 and 2 brick, respectively. Meanwhile, other classes of brick than those mentioned above are classified with no water absorption limit.
Figure 1: Interlocking Compressed Earth Brick (ICEB)
Figure 2: Interlocking Brick Teaching Factory, UMS
2. Materials and Methods 2.1 Materials
The materials used in this research were the Ordinary Portland Cement (OPC), river sand, clay soil, waste rubber tyre (WRT) in the form of crumb particles, and water treatment sludge (WTS).
The clay soil was obtained from the UMS site area in Kota Kinabalu, Sabah. It was first dried and then crushed using the crusher machine at the UMS Interlocking Brick Teaching Factory. The sand used was river sand. The WRT was provided by the Hoyu Tayar Sdn. Bhd. It was in the form of fine material with the gradation closed to that of sand and used to partially replace the clay soil at 0, 5%, 10% and 15% to produce the interlocking compressed rubberized earth brick (ICREB).
Meanwhile, the WTS was obtained at the water treatment pond around Kota Kinabalu area. The WTS was first cleaned by immersing it in the water so that all floated particles can be removed.
Then, it was pre-treated by heating in the oven at 100°C for 24 hours. The WTS was used to replace the sand at 10, 30 and 50% to produce interlocking compressed sludge-earth brick (ICSEB). The mix proportions of the green ICREB and ICSEB bricks are shown in Table 1.
Table 1: Mix proportion of the ICREB and ICSEB Brick Samples
Sample Cement/Sand/Soil Ratio % replacement
Soil Sand Cement WRT WTS
Control 1 2 3 0 0
ICREB-5 1 2 3 5 -
ICREB-10 1 2 3 10 -
ICREB-15 1 2 3 15 -
ICSEB-10 1 2 3 - 10
ICSEB-30 1 2 3 - 30
ICSEB-50 1 2 3 - 50
2.2 Production of the ICREB and ICSEB Bricks
The ICREB and ICSEB bricks were produced at the Interlocking Brick Teaching Factory, UMS, Kota Kinabalu, Sabah (Fig.2). The production started with mixing the dry raw materials using the mixer machine. The water was then added gradually until it reached a suitable consistency. The water content was in the range of 10-15%. After that, the mixtures were conveyed to the compression chamber through the rotating belt. Finally, the mixtures were compressed automatically to produce brick samples. The curing process was started soon after its production by water sprinkling twice per day for at least 7 days.
2.3 Testing Methods 2.3.1 Density Test
The density of the bricks was determined in according to ASTM C134. Five (5) units of the ICREB and ICSEB samples from each mixture were tested. The average density equals to the total mass divided by its total volume. This test indicates that an object made from a comparatively dense material will have less volume than an object of equal mass from some less dense substance.
2.3.2 Compressive strength Test
The compressive strength of the brick was tested based on the BS3921:1985 in dry condition. The procedure started with clearing the surface of the compressive machine and other extraneous material form the surface of the brick was removed. The brick was then placed between the plate to take up irregularities and to ensure uniform bearing. The load was then applied slowly to avoid shock. The maximum load obtained was recorded and the strength was calculated by dividing the maximum load with the area of the ICREB and ICSEB samples.
2.3.3 Water absorption test
The capability of the ICREB and ICSEB to absorb water was determined by 24 hours water immersion test (BS3921:1985). This method allows water to be absorbed into pores. Prior to testing, the brick samples were dried in the ventilated oven at a temperature of 105-115°C until it reached constant mass. The specimen was then cooled at room temperature and weight (W1) was recorded. The samples were then immersed completely in the water for 24 hours. After that, the samples were removed from the water and wiped using a damp cloth. The wet weight of samples (W2) was then recorded. The water absorption is given by the following formula:
Water absorption = [(W2 – W1)/W2] x 100 Where
W1 = dry mass W2 = wet mass
4. Results and Discussion
4.1 Density of the ICREB and ICSEB Bricks
The density of the ICREB is shown in Fig.3. With the addition of the WRT, it can be seen that the density of the ICREB samples was reduced compared to the control ICEB sample. From Fig.3, the density of the ICREB samples increases with the increase of the curing age. It was also noted that as the replacement percentages increased, the densities of the specimens decreased. An inverse relation can be seen between the amount of rubber replaced and densities of the specimens. The reason for this is because of the low specific gravity of the rubber particles compared to clay soil.
When added into the mixtures, an increase in the rubber content increased the air content, which in turn reduced the unit weight of the brick samples. For example, at 15% replacement of rubber content at 28 days, the density diminished to about 85% of the control ICEB. The reduction in density occurred because of the low specific gravity of the crumb rubber (0.901-0.914) with respect to that of sand (2.65-2.67) and soil (2.60). Furthermore, due to its non-polar in nature, rubber particles have the ability to attract and entrap large amounts of air, thus reducing the density of the specimen (Ana et al., 2018). Another reason was because of the poor bonding between rubber particles and cement. Rubber crumb acted as void in the cement matrix which increased its volume and resulted to reduction in the density.
This finding was consistent with previous researchers which stated that rubber particles provide a porous effect between the rubber and the cement matrix since it was less stiff than the cement (Bustamante et al., 2015). In addition, the rubber particles are less reactive and reduce the speed of pozzolanic reaction of cement resulting in less amount of calcium silicate hydrate (CSH) gel produced and the bricks were tended to decrease in weight because the function of CSH gel was to occupy the large voids within the paste and make it denser (Rafat and Paulo, 2018). Therefore, as the amount of crumb rubber increased, less production of CSH gel causes some of the voids were not filled up or occupied within the brick microstructure and lead to the density reduction of the specimen.
The density of ICEBS is shown in Fig.4. A similar trend was also observed for all ICSEB samples cured at 14 days and 28 days period. The density of all ICSEB increased as the curing age increased from 14 days to 28 days. The highest percentage of differences between the curing periods was shown by ICSEB-50 with a difference of 2.8%. This may be due to the sludge gives a higher void ratio and the effect stabilizer such as cement during the curing period that gives densification of brick, thus making the brick denser. Based on the graph, it shows that the lesser the percentage of sludge replacement, the higher the density of the brick.
Figure 3: Density of the ICREB Brick at 14 days and 28 days Curing Ages
Figure 4: Density of the ICSEB Brick at 14 days and 28 days Curing Ages
In accordance with ASTM C90, the concrete masonry units are classified into three (3) different categories based on the oven dry unit weight. These categories are lightweight (< 1680 kg/m3), medium weight (1680 – 2000 kg/m3) and normal weight (>2000 kg/m3). Based on the findings, the densities of all ICREB and ICSEB brick samples fall within the lightweight brick. This result is favourable in creating lightweight construction ICEB with great advantage in handling and transportation which saves fuel and energy.
1620 1562.67 1466.67 1397.33
1680 1632 1520 1456
0 500 1000 1500 2000
C O N T R O L I C R E B - 5 I C R E B - 1 0 I C R E B - 1 5
Density, kg/m³
ICEREB Samples 14 days
1481.17 1476.27 1469.87 1448.33
1512.5 1511.7 1507.2 1489.1
1400 1420 1440 1460 1480 1500 1520
Control ICSEB-10 ICSEB-30 ICSEB-50
Density, kg/m³
ICSEB Samples 14 days 28 days
4.2 Compressive strength of the ICREB and ICSEB Bricks
The compressive strength results of the ICREB and ICSEB are shown in Fig.5 and Fig.6, respectively. Based on the results, it can be observed that there are two (2) factors influencing the compressive strength of the green ICEBs, which are the percentage of replacement and curing period. For the first factor, as the replacement percentage increased, the compressive strength decreased, that is the replacement percentage is inversely proportional to the compressive strength.
According to Fig.5, it can be stated that all ICREB samples of different percentages of replacement are showing a decrease in strength as the amount of the rubber used was increased. The decreased in the compressive strength using rubberized interlocking brick was possibly due to weak bonding between the rubber particles and cement paste, as compared to cement paste and natural aggregates or sand. On the other hand, the present of rubber within the cement mortar phase has softened the matrix, hence rapid development of cracks around the rubber particles while loading leads to quick failure of the specimen (Jegović et al., 2011). It was found that ICREB-5 has shown compressive strength which satisfies the minimum standard requirement with a strength 6.91 MPa. Other samples have not met the minimum requirement as per BS3621:1985. Hence, for using WRT in the ICEB production, 5% of WRT replacement to the clay content is sufficient to produce good ICEB brick.
A similar trend was also observed for ICSEB samples. Based on Fig.6, it clearly shows that the compressive strength decreases as the percentage of sludge replacement increase. This may be related to the microstructure of the ICSEB. With the presence of WTS as partial sand replacement, the density of the ICSEB was reduced. The WTS has a lower fineness modulus (2.45) compared to sand (3.32), hence the density reduced and affected the compressive strength of the ICSEB produced. As stated by Mohammed and Hassan (2015), lower fineness modulus of sand could result in a lower density of brick which leads to a lower compressive strength.
According to the second factor, the compressive strength is directly proportional to the curing age.
The control ICEB bricks showed compressive strength of 7.11 MPa at 14 days. As the curing age increased to 28 days, the compressive strength was also increased to 8.49 MPa, which showed an increment of 19%. Similarly, the increase in strength was also observed for ICREB-5, ICREB-10 and ICREB-15 with increments of 93%, 42% and 127%. The same trend was also observed for ICSEB. All ICSEB have shown greater strength at 28 days curing with increment of 29%, 26%
and 31% for ICSEB-10, ICSEB-20 and ICSEB-30, respectively as compared to 14 days strength.
The curing period has aided the hydration process of the cement and thus giving strength to the brick by producing a more compact and denser bricks microstructure. The curing could also prove to be essential for the internal movement of stabilizing agents such as limestone which is the most abundant composition of cement. For ICSEB, it was noticed that all replacement levels (10-50%) were sufficient to produce ICEB brick with good strength (>5 MPa).
Figure 5: Compressive Strength of the ICREB Brick at 14 days and 28 days Curing Ages
Figure 6: Compressive Strength of the ICSEB Brick at 14 days and 28 days Curing Ages
14 days 28 days
Control 7.11 8.49
ICREB-5 3.58 6.91
ICREB-10 3.14 4.47
ICREB-15 1.32 2.99
01 23 45 67 89
COMPRESSIVE STRENGTH, MPA
CURING AGE, DAY
Control ICREB-5 ICREB-10 ICREB-15
14 days 28 days
Control 7.11 8.49
ICSEB-10 6.32 8.17
ICSEB-30 6.02 7.56
ICSEB-50 4.35 5.72
02 46 108
Compressive strength, MPa
Curing age, day
Control ICSEB-10 ICSEB-30 ICSEB-50
4.3 Water Absorption of the ICREB and ICSEB Bricks
The water absorption results of ICREB and ICSEB bricks have been tabulated and showed in Fig.7 and Fig.8, respectively. Referring to Fig.7, the water absorption capacities in the four (4) mixtures were increased with increasing percent component of rubber crumb. The water absorption at 14 days were 11.04%, 13.18%, 15.62% and 19.20% for ICREB-0, ICREB-5, ICREB-10 and ICREB- 15%, respectively. This indicates that the composite brick containing more percentage of rubber absorbed more water during the wet curing or hydration process. The reason for this behaviour was possibly due to the existence of capillaries which were filled with water in the mixture or raw materials paste containing rubber during wet curing (Bustamante et al., 2015). In addition, poor bonding between rubber particles and cement paste resulted to the rubber-cement surface interface which acts as the bedding for pressurized water to flow around the concrete matrix (Ganjian et al., 2009). The results indicated that the bricks produced from four (4) mixtures had desirable water absorption properties with values lower than allowable requirement.
Water absorption is one of the most significant parameters in developing good bond between brick and mortar. A brick with low water absorption capacity is better in resisting the volume changes which prevents possible cracking of the bricks and structural damage in buildings. It would likewise prevent cracking in the event of freezing and thawing due to less water inside the pores.
The result further showed that the water absorption capacity is not extremely low with values of 7.20% to 19.20%. Too little water absorption is undesirable because rainwater that enters the pores would tend to run off very quickly towards the joints and may find its way into the building as well as reduce the durability of the mortar.
As shown in Fig.8, the water absorption of the ICSEB was lower at 28 days curing as compared to 14 days curing. The lowest water absorption percentage of both curing ages was shown by ICSEB-10. The water absorption increased as the percentage of clay replacement increased due to the high water absorption of sludge compared to sand. Reduce in the water absorption when the curing age increases was due to the production of calcium silicate hydrate (CSH). According to Muntahor (2011), CSH is the main product of hydration of Portland cement and is considered to be the primary strength for the cement strength-based material such as compressed stabilized earth brick. The process of curing developed other solid hydration product in the ICEB which will results a more compacted bricks which decreases the porosity of the brick. This results in a lower value of water absorption percentage.
According to BS3921:1985, low water absorption limit was specified for Engineering A and B, and Damp-proof course brick with the absorption of 4.5% and 7.0%, respectively. Bricks for all other classes or applications than those mentioned above are not restricted to any water absorption limit (no limit), which means that both ICREB and ICSEB bricks produced in this research have met the requirement of BS3921:1985 and can be categorized as all other classes.
Figure 7: Water Absorption of the ICREB Brick at 14 days and 28 days Curing Ages
Figure 8: Water Absorption of the ICSEB Brick at 14 days and 28 days Curing Ages
5. Conclusion
1. The ICREB and ICSEB brick samples can be categorized as lightweight brick with densities of less than 1680 kg/m3. These results are favourable for easy handling and transportation which saves fuel and energy.
2. The addition of crumb rubber leads to undesirable reduction in the compressive strength of the
7.20 9.53 10.93
13.89
11.04 13.18 15.62
19.20
0.00 5.00 10.00 15.00 20.00 25.00
Control ICREB-5 ICREB-10 ICREB-15
Water absorption, %
ICREB Samples 14 days
17.16 17.02 17.09 17.5
14.84 14.30 14.36 14.77
0 5 10 15 20
Control ICSEB-10 ICSEB-30 ICSEB-50
Water absorption, %
ICSEB Samples 14 days
4. Partial replacement of sand with 10 – 50% of WTS had produced ICSEB with good compressive strength which satisfies the minimum requirement as stated in the BS3921:1985 (minimum 5 MPa).
5. 50% of sand replacement by WTS can be considered as an appropriate percentage for the ICEB production. This would lead to lower production cost, besides minimizing environmental impacts due to sludge disposal.
6. The water absorptions of all ICREB and ICSEB samples are acceptable within the class of ‘all other classes’ with range of 7.20 – 19.20%.
6. Acknowledgement
The authors gratefully acknowledge the financial support for this research from Ministry of Higher Education Malaysia research grant (LRGS 0008-2017). Authors also acknowledge the Hoyu Tayar Sdn Bhd for the support in research material supply.
References
Abbas, M., Lucas, B., John, V. S., Stefan, M., Glen, R., Md Tareq, R., Halenur, K., Mehdi M., Arul, A., Suksun, H., & Farshid, M. (2020). Recycling Waste Rubber Tyres in Construction Materials and Associated Environmental Considerations: A Review. Resources, Conservation and Recycling, 155, 104679.
Ana, B., Marija, J. R., Martina, P., Nina, Š. (2018). Influence of Recycled Tire Polymer Fibers on Concrete Properties. Cement and Concrete Composites, 91, 29-41.
Ashraf, M. A., Maah, M. J., Yusoff, I., & Wajid, A. (2011). Sand Mining Effects, Causes and Concerns : A Case Study from Bestari Jaya , Selangor , Peninsular Malaysia. 6(6), 1216–1231.
ASTM C134-95. (1999). Standard Test Methods for Size, Dimensional Measurements, and Bulk Density of Refractory Brick and Insulating Firebrick, ASTM International, West Conshohocken, PA.
ASTM C90-08. (2008). Standard Specification for Loadbearing Concrete Masonry Units, ASTM International, West Conshohocken, PA.
Ayesha S., Md. Abdullah, A. M., Rayed, A., Mugahed, A.Y.H., Farhad, A., Hisham, A. (2019).
Properties and Utilizations of Waste Tire Rubber in Concrete: A Review. Construction and Building Materials, 224, 711-731.
Bano, S., & Syed, A. A. (2019). Application of Waste Tyre in Highway Pavement: A Literature Review. Journal of Engineering and Environmental Technology, 5 (8), 556-562
Benlalla, A., Elmoussaouiti, M., Dahhou, M., Assafi, M. (2015). Utilization of Water Treatment Plant Sludge in Structural Ceramics Bricks. Applied Clay Science, 118, 171-177.
BS3921:1985. (1985). British Standard Specification for Clay Bricks, British Standard Institution.
Bustamante, A., Dablo, G. & Sia, R., & Arazo, R. (2015). Physical and Mechanical Properties of Composite Brick from Cement Mortar, Fly Ash, and Rubber Crumbs. International Journal of Research in Engineering and Technology, 4(10), 1-5.
Cong, M., Bin, Z., Yingzhuang, H., Fei, L., Guangcheng, L. & Yinfei, D. (2020). Preparation and Properties of Sustainable Magnesium Phosphate Cement Composites with Recycled Tire Rubber Particles. Journal of Cleaner Production, 262, 121253.
Ganjian, E., Khorami, M., and Maghsoudi, A. A. (2009). Scrap-tyre-rubber Replacement for Aggregate and Filler in Concrete. Construction and Building Materials, 23(5),1828-1836.
Haikal, K.A.H. (2019). The Engineering Properties of Interlocking Compressed Earth Brick Using Water Treatment Plant Sludge as Fine Aggregates. Unpublished Undergraduate Thesis, Faculty of Engineering, Universiti Malaysia Sabah.
Jegović, D., Baricevic, A., & Serdar, M. (2011). Durability Properties of Concrete with Recycled Waste Tyres. 12th International Conference on Durability of Building Materials and Components Porto. 1659-1667.
Kemkar, N. (2002). The Scrap Tire Problem in Rhode Island:Analysis and Recomendations.
Rhode Island: Brown University.
Lee, Y.H., Shek, N.P., & Mohammad, S. (2017). Structural Performance of Reinforced Interlocking Blocks Column. Construction and Building Materials, 142, 469–481.
Lulu, L., Guojun, C., Jun, Z., Xiaoyan, L. & Kai, L. (2020). Evaluation of Engineering Properties and Environmental Effect of Recycled Waste Tire-Sand/Soil in Geotechnical Engineering: A Compressive Review. Renewable and Sustainable Energy Reviews, 126, 109831.
Malvika, I.P., Nipuna, M., Raina, T.R., Sreelakshmi A.V., Kripa K.M. (2017). Design of Interlocking Block and Replacement of Msand by Concrete Roof Tile Waste. International Research Journal of Engineering and Technology (IRJET), 4(5), 1224-1229.
Melik, B., Habib, T., & Mohamed, R. (2019). Influence of Waste Tire Rubber Fibers on Swelling Behavior, Unconfined Compressive Strength and Ductility of Cement Stabilized Bentonite Clay Soil. Construction and Building Materials, 208, 304-313.
Mngeni, A., Musampa, C. M., & Nakin, M. D. V. (2016). The Effects of Sand Mining on Rural Communities. WIT Transactions on Ecology and The Environment, 210, 443–453.
Mohammed, T. U., & Hassan, M. M. (2016). Utilization of Brick Fine Aggregate in Concrete Utilization of Brick Fine Aggregate in Concrete. Journal of Materials in Civil Engineering, 27(JUNE 2015), B4014005.
Muntohar, A. S. (2011). Engineering Characteristics of the Compressed-Stabilized Earth Brick.
Construction and Building Materials, 25(11), 4215–4220.
https://doi.org/10.1016/j.conbuildmat.2011.04.061
Oikonomou, N., & Mavridou, S. (2009). The Use of Waste Tyre Rubber in Civil Engineering
Rafat, S., & Paulo, C. (2018). Supplementary Cementitious Materials in Concrete:
Characterisation, Properties and Applications. Woodhead Publishing, United Kingdom.
Sandra, K., A., and Thiruvangodan, L. (2006). Waste Tyre Management in Malaysia. PhD Thesis, Faculty of Environmental Studies, Universiti Putra Malaysia.
Srinivasan, K., Vazhviniyan, R., Mohankumar, L., & Palpandi, K. (2016). Replacement of Fine Aggregate Using Sludge in Concrete. International Research Journal of Engineering and Technology, 3(5), 1989-1993.
Tantawy, M.A., Ramadan, S.A.M. (2017). Middle Eocene Clay from Goset Abu Khashier:
Geological Assessment and Utilization with Drinking Water Treatment Sludge in Brick Manufacture. Applied Clay Science, 138, 114-124.
Yang, L., Shuai, Z., Ruijun, W., & Faning, D. (2019). Potential Use of Waste Tire Rubber as Aggregate in Cement Concrete – A Comprehensive Review. Construction and Building Materials. 225, 1183-1201.
Yu,e L., Yan, Z., Christopher, W.K.C., Alexandra, K., Danda, L., Phuong, N.P., Jianyin, H., &
Rafat, S. (2020). Utilization of Drinking Water Treatment Sludge in Concrete Paving Blocks:
Microstructural Analysis, Durability and Leaching Properties. Journal of Environmental Management, 262, 110352.Harrington, A. (2005). Modern Social Theory. 1-13.
