Abstract Recent failures of transmission towers during thunderstorm events underline the need for a clearer understanding of how different design codes characterize non-synoptic wind loads. This study compares the thunderstorm-related wind parameters specified in four major standards – DL/T 5551-2018, ASCE 74-2020, IEC 60826-2017, and BS EN 50341-2012 – and evaluates their influence on wind-load predictions and the wind-induced behavior of transmission tower–line systems. Results show that ASCE 74 produces the largest wind loads, whereas DL/T 5551 yields the smallest, with the maximum difference in tower-body wind forces reaching 12.8 %. Wind direction significantly affects the vertical distribution of wind pressure, and a 45° incidence angle is identified as a critical loading condition due to geometric shielding effects. Parametric analyses further indicate that wind speed overwhelmingly governs the system’s structural response, while span length introduces comparatively minor variations. Conductor displacements consistently exhibit much larger horizontal than vertical components as a result of dominant lateral aerodynamic actions. These findings demonstrate that the choice of design code can markedly alter the assessed wind effects on transmission tower–line systems. The study provides a scientific basis for determining thunderstorm wind loads and underscores the necessity of adopting provisions tailored to convective storm environments to ensure adequate safety margins in transmission-line design.
Liu et al. (Tue,) studied this question.