Mixed rime ice accretion is one of the most common ice types threatening transmission line safety. Addressing the prior lack of experiments on mechanical properties of mixed rime ice accretion using real multilayered concentric stranded conductors as substrates

this study conducts in-situ artificial icing wind tunnel tests on actual transmission conductors. First

typical ice specimens (glaze ice

mixed rime ice

and soft rime ice) are fabricated by controlling environmental parameters: temperature

droplet diameter

wind speed

and liquid water content. Subsequently

variations in ice mechanical properties with porosity are quantified by measuring the normal adhesion strength and tangential adhesion strength at the ice-conductor interface

along with the tensile strength of bulk ice. Then

a constitutive model and fracture criterion capable of quantitatively characterizing the mechanical properties of mixed rime ice accretion on transmission conductors with porosity effects are proposed. Experimental results demonstrate that: 1) Porosity is a critical factor affecting ice mechanical properties; 2) The multilayered concentric stranded surface of real conductors results in greater tangential adhesion strength than normal adhesion strength at the mixed rime ice-conductor interface—directly contradicting results from smooth metal substrates; 3) Mixed rime ice accretion exhibits transversely isotropic material behavior

and the maximum stress criterion effectively characterizes its fracture under porosity variations. This research provides fundamental insights into mechanical performance of transmission line mixed rime ice accretion under realistic conditions

offering critical support for simulating ice-shedding dynamics during mechanical /thermal de-icing and natural ice shedding process

and for optimizing anti-icing strategies.