In recent years

the issue of defects in the buffer layers of high-voltage cables has garnered significant attention due to their widespread occurrence and the substantial potential damages they pose. Although progress has been made in understanding the mechanisms behind these defects and in developing detection methods

effective repair solutions remain limited. This study addresses this challenge by proposing a novel repair material: a two-component

additive liquid silicone rubber-based compound that utilises vinyl silicone oil as its base. The electrical

thermal

and mechanical properties of the cured silicone-based repair fluid are thoroughly analysed. To evaluate its effectiveness

an experimental platform was constructed using a 17-m-long

110 kV retired cable with known buffer layer defects. A specialised injection process was developed to facilitate the application of the repair fluid. The thermal characteristics

buffer layer voltage distribution

and partial discharge behaviour of the defective cable were analysed both before and after the repair. The results indicate that following the repair

the cable's heat dissipation capacity under full load increased by 6.25%. Additionally

the buffer layer voltage at the rated voltage (U0) decreased from 1.97 to 0.34 V

representing an 82.74% reduction. Notably

no partial discharge signals exceeding background noise were detected post-repair. This study demonstrates the effectiveness of the addition-cure liquid silicone rubber-based semi-conductive material in repairing cable buffer layer defects and provides valuable experimental support for its practical application in engineering.