Optimization techniques for identifying soil parameters in geotechnical engineering: Comparative study and enhancement

Abstract

A comparative study of optimization techniques for identifying soil parameters in geotechnical engineering was first presented. The identification methodology with its 3 main parts, error function, search strategy, and identification procedure, was introduced and summarized. Then, current optimization methods were reviewed and classified into 3 categories with an introduction to their basic principles and applications in geotechnical engineering. A comparative study on the identification of model parameters from a synthetic pressuremeter and an excavation tests was then performed by using 5 among the mostly common optimization methods, including genetic algorithms, particle swarm optimization, simulated annealing, the differential evolution algorithm and the artificial bee colony algorithm. The results demonstrated that the differential evolution had the strongest search ability but the slowest convergence speed. All the selected methods could reach approximate solutions with very small objective errors, but these solutions were different from the preset parameters. To improve the identification performance, an enhanced algorithm was developed by implementing the Nelder-Mead simplex method in a differential algorithm to accelerate the convergence speed with strong reliable search ability. The performance of the enhanced optimization algorithm was finally highlighted by identifying the Mohr-Coulomb parameters from the 2 same synthetic cases and from 2 real pressuremeter tests in sand, and ANICREEP parameters from 2 real pressuremeter tests in soft clay.

Investigation of Collapsed Building Incidents on Soft Marine Deposit: Both from Social and Technical Perspectives

“…Therefore, due to the occurrence of creep, the decrease in the pore volume for Wenzhou clay could be more pronounced, thus promoting the development of differential settlement (δ). According to Yin [55,56], the tertiary creep of a soil contributes significantly to the long-term deformation of foundations of the highly sensitive clays [57][58][59]. Thus, this creep behavior becomes one of the significant factors contributing to this incident.…”

A multiscale approach for investigating the effect of microstructural instability on global failure in granular materials

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Evaluation of foam conditioning effect on groundwater inflow at tunnel cutting face

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