Estimating the strength of soil stabilized with cement and lime at optimal compaction using ensemble-based multiple machine learning

  • 0Department of Civil Engineering, Michael Okpara University of Agriculture, Umudike, Nigeria. konyelowe@mouau.edu.ng.

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Summary

This summary is machine-generated.

This study enhanced cohesive soil strength using cement and lime, with machine learning models accurately predicting unconfined compressive strength (UCS). Gradient Boosting and K-Nearest Neighbors achieved 95% accuracy, highlighting key factors like maximum dry density and consistency limits.

Area Of Science

  • Geotechnical Engineering
  • Environmental Geotechnics
  • Materials Science

Background

  • Cohesive soils require stabilization for pavement subgrades and landfill liners when unconfined compressive strength (UCS) is below 200 kN/m².
  • Improving mechanical properties is crucial for structural integrity and environmental protection in geotechnical applications.
  • Machine learning offers advanced analytical tools for predicting soil behavior and optimizing material properties.

Purpose Of The Study

  • To comparatively assess machine learning models for predicting the unconfined compressive strength (UCS) of cohesive soil stabilized with cement and lime.
  • To identify the most effective ensemble-based machine learning techniques for soil stabilization analysis.
  • To determine the key factors influencing the UCS of reconstituted cohesive soils.

Main Methods

  • Utilized ensemble-based machine learning classification (Gradient Boosting, CN2, Naïve Bayes, SVM, SGD, K-NN, Decision Tree, Random Forest) and symbolic regression (ANN, RSM).
  • Trained and tested models on 190 experimental data points, considering inputs: cement, lime, liquid limit, plasticity index, optimum moisture content, and maximum dry density.
  • Performed correlation matrix and sensitivity analysis to identify influential parameters on UCS.

Main Results

  • Gradient Boosting (GB) and K-Nearest Neighbors (K-NN) models achieved the highest accuracy (95%).
  • CN2, Support Vector Machine (SVM), and Decision Tree (Tree) models showed approximately 90% accuracy.
  • Maximum dry density (MDD), consistency limits (LL, PI), and cement content significantly influenced UCS, while optimum moisture content (OMC) had a negligible impact.

Conclusions

  • Ensemble machine learning models, particularly GB and K-NN, are highly effective for predicting the UCS of stabilized cohesive soils.
  • Optimal soil stabilization can be achieved by focusing on MDD, consistency limits, and cement content.
  • The findings provide a valuable framework for field applications in designing stable geotechnical structures with reconstituted soils.

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