Impact Resistance and Energy Absorption Analysis of Crossover Frames with Different Materials

To address the insufficient impact resistance of crossover frames in UHV transmission projects, this study investigates the impact response and energy absorption of undamped frames using Q420 steel, 45 steel, 6061-T6 aluminum alloy, and EP fiberglass. An energy conversion model is established, and 1:20 scaled tests and finite element simulation are conducted over 0.5–5.0 m drop heights. The results show that Q420 steel achieves the highest energy absorption; aluminum alloy balances specific energy absorption and lightweight performance; 45 steel performs moderately; fiberglass reduces peak force but has limited energy dissipation and brittle fracture risk. The efficiency of metals rises with drop height, while that of fiberglass shows a slight decline. This work provides a theoretical basis for material selection and crossover frame optimization.