Probabilistic evaluation of vibratory probe compaction effects on liquefiable soil considering spatial variability

This study assesses the role of the vibratory probe compaction method (VPCM) in mitigating liquefaction hazards, considering the spatial variability of the cyclic resistance ratio (CRR). A Bayesian framework was employed to identify statistically homogeneous CRR layers and the random field model parameters to accurately determine the impact of VPCM on CRR at different depths. The liquefiable to total soil thickness ratio was probabilistically determined using Monte Carlo simulations to identify liquefiable soil layers and quantify liquefaction severity. Results reveal that VPCM homogenizes CRR statistical properties across soil layers during treatment. Shallow layers showed reduced CRR uncertainty and scale of fluctuation due to loosening, whereas deeper layers exhibited improved liquefaction resistance but increased CRR variability. Probabilistic analysis was conducted to evaluate liquefaction risk in statistically homogeneous soil layers. Deep liquefiable soil layers transitioned from severe liquefaction susceptibility to slight or no liquefaction after treatment. These findings highlight VPCM's dual role: effectively reducing liquefaction severity in deep layers while introducing depth-dependent trade-offs in soil homogeneity and uncertainty. The method offers a viable mitigation strategy when prioritizing deep-layer stability over shallow-layer CRR consistency.