Physical Model Tests and Stability Analysis of Slopes Based on Loading Rod Stress Compensation

With the increasing number of excavation slope projects, slope stability has become an important factor affecting engineering safety. A slope project in Jianning County, Fujian Province was taken as the research object. Indoor physical model tests of slopes were carried out using loading rods to apply stress compensation. During the failure process, surface displacement, internal displacement, earth pressure, and volumetric strain were monitored to analyze their evolution characteristics. In addition, anchor supported slope model tests and FLAC3D numerical simulations were conducted to compare slope stability under different support conditions. The results show that the loading rod method can effectively realize stress compensation in slope models. The slope model remains stable under multiple times of its self-weight. Under single row loading conditions, the 20 cm and 16 cm groups can bear four times of the self-weight, while the 12 cm group can bear five times of the self-weight. Under three row loading conditions, the 12 cm group can bear six times of the self-weight without overall instability. This confirms the feasibility of achieving stress similarity in indoor slope model tests using the loading rod method. Anchor support significantly improves slope stability. The safety factor of the slope model increases from 0.86 without support to 1.17 with anchor support. The volumetric strain shows high sensitivity to deformation before slope failure. It can be used as an important reference index for slope stability analysis and failure warning. The research results provide a reference for selecting loading methods in indoor slope model tests and for evaluating engineering slope stability.