To investigate the actual working mechanism of anti-slide piles, an integrated monitoring system combining distributed fiber Bragg grating (FBG) sensors and flexible inclinometers was deployed in a highway landslide control project. FBG cables and inclinometer tubes were implanted in one single-row cantilever pile (No.20) and two double-row portal-frame piles (No.48 front-row and No.71 rear-row) with anchor cables, allowing for simultaneous measurement and comparative study of the internal force (bending moment) and deformation (displacement) fields. The results reveal that single-row piles exhibit a tightly coupled internal force-deformation relationship, with coincident bending moment and displacement inflection points. In contrast, double-row piles display a systematic decoupling: peak bending moments shift to greater depth while maximum displacements remain shallow, caused by load redistribution through the capping beam. Safety evaluation shows that the measured maximum bending moments utilize only 7.06%–10.75% of the design capacity, confirming linear elastic behaviour and substantial safety reserves. The study demonstrates the value of multi-source data fusion for structural diagnosis and performance optimization in slope engineering.
Feng et al. (Tue,) studied this question.