Scholarlink

<p>Unconfined compressive strength (UCS) and California Bearing Ratio (CBR) are critical for assessing soil strength under vertical loading, especially in fine-grained soils, which often fail to meet the required standards for road and embankment projects. This study investigates the impact of cement and fly ash on enhancing UCS and CBR through soil stabilization. A total of 211 soil samples, including untreated, cement-treated, and fly ash-treated soils, were analyzed using Pure Quadratic (PQ), Interaction (IA), and Full Quadratic (FQ) regression models incorporating CaO, SiO₂, Al₂O₃, MgO, Fe₂O₃, maximum dry density, optimum moisture content, and curing time. The FQ model exhibited the best performance (UCS: R<sup>2</sup> = 0.88, root mean square error (RMSE) = 66.3 kPa; CBR: R = 0.95, RMSE = 6.6%). Under optimal oxide conditions, UCS increased from 95 kPa (untreated) to 540 kPa (stabilized), and CBR rose from 3.2% to 18.5%, demonstrating significant enhancements. Sensitivity analysis revealed that CaO and curing time predominantly influence UCS, while curing time and optimum moisture content govern CBR. These results highlight the practical advantage of a chemistry-driven stabilization approach over conventional dosage-based models for efficiently improving soil strength. The results showed an increase in both UCS and CBR with the incorporation of these materials, though the improvements were asymmetrical depending on the cement and fly ash dosage. The variation is attributed to changes in the soil–cement or soil-fly ash matrix caused by chemical oxides such as silica, alumina, and calcium. Calcium oxide and curing time were the most influential factors for UCS, while curing time and optimum moisture content were the key factors for CBR. This study suggests a high-calcium oxide soil-additive matrix to enhance UCS and CBR in fine-grained soils.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A Unique Framework for UCS and CBR Prediction: The Role of Chemical Oxides in Stabilizing Fine-Grained Soils with Fly Ash and Cement

  • 期刊论文

  • 发表日期：

    2026年3月2日

查看全文
  • Hunar Farid Hama Ali,
  • Ahmed Salih Mohammed

摘要

Unconfined compressive strength (UCS) and California Bearing Ratio (CBR) are critical for assessing soil strength under vertical loading, especially in fine-grained soils, which often fail to meet the required standards for road and embankment projects. This study investigates the impact of cement and fly ash on enhancing UCS and CBR through soil stabilization. A total of 211 soil samples, including untreated, cement-treated, and fly ash-treated soils, were analyzed using Pure Quadratic (PQ), Interaction (IA), and Full Quadratic (FQ) regression models incorporating CaO, SiO₂, Al₂O₃, MgO, Fe₂O₃, maximum dry density, optimum moisture content, and curing time. The FQ model exhibited the best performance (UCS: R2 = 0.88, root mean square error (RMSE) = 66.3 kPa; CBR: R = 0.95, RMSE = 6.6%). Under optimal oxide conditions, UCS increased from 95 kPa (untreated) to 540 kPa (stabilized), and CBR rose from 3.2% to 18.5%, demonstrating significant enhancements. Sensitivity analysis revealed that CaO and curing time predominantly influence UCS, while curing time and optimum moisture content govern CBR. These results highlight the practical advantage of a chemistry-driven stabilization approach over conventional dosage-based models for efficiently improving soil strength. The results showed an increase in both UCS and CBR with the incorporation of these materials, though the improvements were asymmetrical depending on the cement and fly ash dosage. The variation is attributed to changes in the soil–cement or soil-fly ash matrix caused by chemical oxides such as silica, alumina, and calcium. Calcium oxide and curing time were the most influential factors for UCS, while curing time and optimum moisture content were the key factors for CBR. This study suggests a high-calcium oxide soil-additive matrix to enhance UCS and CBR in fine-grained soils.