Model test is a common method to study the bearing peculiarity of pile foundation. The influence of overlying soil thickness and overburden pressure on the bearing capacity of soft rock-socketed pile should be considered in the physical model test of mini piles in soft rock. In this paper, the influence of coverage on the bearing characteristics of rock-socketed sections is studied by finite element analysis, and the modelling method of equivalent overburden pressure is proposed. This method can be used to study the carrying peculiarity of soft rock-socketed pile and reveal the failure mechanism of pile tip. The development of pile model test technology considering overburden pressure promotes more scientific design methods for pile foundation.

The clay-bearing skarn is a typical swelling rock that exhibits volumetric swelling and mechanical property degradation upon water absorption, causing serious damage to rock engineering. To investigate the swelling behavior of skarn, a new experimental apparatus has been developed to simultaneously measure swelling strain and water content during the water absorption and swelling processes. A series of swelling tests were carried out to investigate the relationship between the swelling strain and the water content. The effects of the clay mineral content on the swelling behavior were analyzed. In addition, the reasons for the swelling of skarn were discussed by comparing the skarn microstructure before and after the swelling tests. It is found that the swelling behavior of skarn exhibits a three-stage characteristic and is positively correlated with the clay mineral content. Particularly noteworthy is that the tests provided unprecedented information about the relationship between the swelling coefficient of skarn and water content. The experimental results can be used to guide parameter selection in long-term simulations on the swelling behavior of the clay-bearing rock, which requires an understanding of water content effects on the coupled hydraulic–mechanical properties governing these processes.

The initiation position should be matched to the joint characteristics of the rock mass to improve blasting performance. Nevertheless, bottom initiation remains the conventional choice in engineering practice, despite limited understanding of how the relative performance of initiation positions varies with joint conditions. In this study, a comprehensive LFPP–TOPSIS-based evaluation method was established by integrating six blasting-performance indices. Its application was illustrated using intact rock blasting simulations, and the resulting ranking was assessed for qualitative plausibility. It was then applied to discrete element simulation results covering 12 joint dip angles and 7 initiation positions. Under the selected indices, weights, and simulated conditions, conventional bottom initiation does not always obtain the highest evaluation score. Offset top initiation and two-point initiation generally rank higher at small to medium joint dip angles, whereas bottom or offset bottom initiation ranks highest at large joint dip angles. A possible mechanism linking initiation position adjustment to blasting performance in jointed rock masses is further discussed. This study provides a numerical basis for comparing initiation-position preferences within the investigated joint conditions.