Analysis of reinforcement effect of different anchoring forces on slope stabilised by prefabricated anchorage cable frame beams

Abstract

Prefabricated anchorage cable frame beams represent a new approach to slope reinforcement, displaying distinct deformation and stress patterns under varying anchoring forces compared to traditional cast-in-place frame beams. This renders the traditional theories and engineering practices of cast-in-place beams inapplicable. Field tests and sophisticated finite-difference simulation models were established to examine the mechanical performance of prefabricated beams under different anchoring forces. Initially, field test results validated the simulation models against measured and theoretical data. Subsequently, the impact of different anchoring forces on slope deformation, structural deformation, and stress in frame beams were explored. The beam pressure at the anchoring point of prefabricated beams was 24 % lower than that of cast-in-place beams, exhibiting a linear relationship with increasing anchoring forces and heightened initial sensitivity. Prefabricated beams showed a 20–30 % reduction in anchoring force loss over traditional beams when the anchoring force is not greater than 40 t. Notably, tensile stress emerges in prestressed prefabricated beams when anchoring forces exceed 50 t. The slope deformation with the increasing of anchoring force can be described by a power function. A new deflection deformation index for frame beams was proposed, showing a 70 % reduction compared to cast-in-place beams. During sliding face degradation, deformation differences between adjacent prefabricated beams weaken the reinforcement effect compared to continuous cast-in-place beams. However, applying sufficient anchoring forces significantly mitigates this effect. A well-calibrated anchoring force ensures superior performance of prefabricated anchorage cable frame beams, with enhanced crack resistance, reduced anchoring force loss, minimal deflection deformation. Moreover, the prefabricated beam structure is easy for local replacement and maintenance. This study can make a reference for the application and design of prefabricated structures for slope stabilisation.