A Study on the Effect of Replacing Coarse Grains in Sub-Base Materials with Concrete Residues on their California Bearing Ratio
Received: 18 February 2025 | Revised: 21 March 2025 | Accepted: 2 April 2025 | Online: 4 June 2025
Corresponding author: Balqees A. Ahmed
Abstract
California Bearing Ratio (CBR) values are critical to the properties of granular subgrade materials and play a significant role in determining the design variables of several flexible pavement design methods. Concrete waste is considered an environmental problem in many regions of Iraq. Therefore, its removal is of significant environmental value when used to improve the properties of certain materials, such as the granular sub-base examined in this study. This research examined the impact of substituting particles measuring 19 mm to 12 mm in granular sub-base materials, class C and D, with crushed concrete waste at replacement rates of 25%, 50%, 75%, and 100% while preserving their gradation characteristics, on the CBR value. The CBR examination results showed that the most significant improvement in the CBR value was observed at a 100% replacement ratio, attaining 55.84% and 57.22% at a 1 mm penetration for the unsoaked C and D samples, respectively, and 63.32% and 48.11% for the soaked condition at a 1 mm penetration for the C and D samples, respectively. The increase in CBR was correlated with an increase in Optimum Moisture Content (OMC) and a decrease in maximum dry unit weight (γdry max), demonstrating that the percentage increase in CBR is non-linear. An increase in CBR may be helpful in the foundation base for many projects.
Keywords:
California Bearing Ratio (CBR), granular sub-base material, crushed concrete waste, improvingDownloads
References
E. L. Singh and E. S. Singh, "Improvement in CBR Value of Soil using Waste Concrete Fines," International Journal of Science Technology & Engineering, vol. 3, no. 09, Mar. 2017.
M. A. Al-Obaydi, M. D. Abdulnafaa, O. A. Atasoy, and A. F. Cabalar, "Improvement in Field CBR Values of Subgrade Soil Using Construction-Demolition Materials," Transportation Infrastructure Geotechnology, vol. 9, no. 2, pp. 185–205, Apr. 2022.
S. T. Ahmed, M. U. Kabir, C. Z. B. Zahid, T. Tareque, and S. Mirmotalebi, "Improvement of subgrade California Bearing Ratio (CBR) using recycled concrete aggregate and fly ash," Hybrid Advances, vol. 5, Apr. 2024, Art. no. 100153.
M. S. Fayaz, "Blending of Recycled Concrete Aggregates for Use in Base Course Construction," International Journal of Innovative Research in Engineering and Management, vol. 9, no. 2, pp. 584–591, Sep. 2022.
A. Al-Taie, E. Yaghoubi, F. Tahmoorian, J. Li, and B. A. Ahmed, "Pavement performance over deep trenches backfilled with recycled aggregates under different compaction efforts," Canadian Geotechnical Journal, vol. 62, pp. 1–26, Jan. 2025.
E. Yaghoubi, A. Al-Taie, M. Disfani, S. Fragomeni, M. Guerrieri, and E. Gmehling, "Cement and fly ash-treated recycled aggregate blends for backfilling trenches in trafficable areas," Transportation Geotechnics, vol. 42, Sep. 2023, Art. no. 101091.
A. Al-Taie, E. Yaghoubi, M. Disfani, S. Fragomeni, and E. Gmehling, "Field Performance Evaluation of Recycled Aggregate Blends Used for Backfilling Deep Excavated Trenches," International Journal of Geomechanics, vol. 24, no. 2, Feb. 2024, Art. no. 04023264.
A. Al-Taie, E. Yaghoubi, E. Gmehling, S. Fragomeni, M. Disfani, and M. Guerrieri, "Recycled aggregate blends for backfilling deep trenches in trafficable areas," Construction and Building Materials, vol. 401, Oct. 2023, Art. no. 132942.
H. A. Mahdi, B. A. Ahmed, and M. D. Ahmed, "Study on Strength Behavior of Expansive Soil Stabilized with Dune Sand and Sodium Silicate," IOP Conference Series: Earth and Environmental Science, vol. 1374, no. 1, Aug. 2024, Art. no. 012035.
A. Budiarto, "The influence of replacement of course aggregate material with crushed stone to the CBR value on Aggregate Class B," in Proceedings of the 4th International Conference on Engineering, Technology, and Industrial Application (ICETIA) 2017, Surakarta, Indonesia, 2018, Art. no. 020033.
R. Malaoui, E. H. Harkati, M. R. Soltani, A. Djellali, A. Soukeur, and R. Kechiched, "Geotechnical Characterization of Phosphate Mining Waste Materials for Use in Pavement Construction," Engineering, Technology & Applied Science Research, vol. 13, no. 1, pp. 10005–10013, Feb. 2023.
E. B. Toka and M. and Olgun, "Performance of granular road base and sub-base layers containing recycled concrete aggregate in different ratios," International Journal of Pavement Engineering, vol. 23, no. 11, pp. 3729–3742, Sep. 2022.
M. Mohanty, S. S. Mohapatra, and S. Nayak, "Efficacy of C&D waste in base/subbase layers of pavement – current trends and future prospectives: A systematic review," Construction and Building Materials, vol. 340, Jul. 2022, Art. no. 127726.
L. Z. Wongbae, C. Kabubo, and A. Owayo, "The Effect of Waste Marble Dust and Corncob Ash on the Engineering and Micro-Structural Properties of Expansive Soil for Use in Road Subgrades," Engineering, Technology & Applied Science Research, vol. 14, no. 2, pp. 13765–13772, Apr. 2024.
M. O. Karkush and S. Yassin, "Using sustainable material in improvement the geotechnical properties of soft clayey soil," Journal of Engineering Science and Technology, vol. 15, no. 4, pp. 2208–2222, Aug. 2020.
Z. K. Abdalqadir, N. B. Salih, and S. J. H. Salih, "Using Steel Slag for Stabilizing Clayey Soil in Sulaimani City-Iraq," Journal of Engineering, vol. 26, no. 7, pp. 145–157, Jun. 2020.
S. B. Saeed and K. A. Rashed, "Evaluating the Uses of Concrete Demolishing Waste in improving the Geotechnical Properties of Expansive Soil," Journal of Engineering, vol. 26, no. 7, pp. 158–174, Jul. 2020.
M. Otieno, Z. Gariy, and C. Kabubo, "An Evaluation of the Performance of Lateritic Soil Stabilized with Cement and Biochars to be Used in Road Bases of Low-Volume Sealed Roads," Engineering, Technology & Applied Science Research, vol. 13, no. 4, pp. 11366–11374, Aug. 2023.
A. Ahmed, M. El-Emam, N. Ahmad, and M. Attom, "Stabilization of Pavement Subgrade Clay Soil Using Sugarcane Ash and Lime," Geosciences, vol. 14, no. 6, Jun. 2024, Art. no. 151.
M. Otieno, C. Kabubo, and Z. Gariy, "Mechanical and Structural Correlation of Lateritic Soil Road Base Stabilized with Cement and Selected Biochars," Engineering, Technology & Applied Science Research, vol. 13, no. 4, pp. 11070–11077, Aug. 2023.
M. D. Ahmed and A. M. Adkel, "Stabilization of Clay Soil Using Tyre Ash," Journal of Engineering, vol. 23, no. 6, pp. 34–51, May 2017.
N. A. Jasim, Q. S. Shafiqu, and M. A. Ibrahim, "The Effect of Adding High-Density Polyethylene Polymer on the Engineering Characteristics for Sandy Soil," Journal of Engineering, vol. 27, no. 9, Sep. 2021, Art. no. 29.
D1883-21 Standard Test Method for California Bearing Ratio (CBR) of Laboratory-Compacted Soils. West Conshohocken, PA, USA: ASTM International, 2021.
D422 Standard Test Method for Particle-Size Analysis of Soils. West Conshohocken, PA, USA: ASTM International, 2014.
D1557-12 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-m/m3)). West Conshohocken, PA, USA: ASTM International, 2021.
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Copyright (c) 2025 Mustafa Musa Salih, Balqees A. Ahmed, Hayder A. Mahdi
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