Which is the strength of the steel core and aluminum strand of the conductor?

Generally speaking, the ACSR conductor is mainly stressed by the steel core, and the aluminum strand is hardly stressed. Some people even equate the breaking force of the conductor to that of the steel core. Later, some things made me doubt the above view. So many aluminum stocks account for the vast majority of the cross-sectional area of the conductor. After all, they are also a metal family. Is it so unbearable in terms of the contribution to the comprehensive strength? Gradually, I have an idea of breaking the casserole to the end. Why not calculate it carefully according to the relevant standards and specifications.

The rated breaking force of conductors with the same structure and the same nominal section may not be the same, and the difference is reflected in the product model. Therefore, it is necessary to understand the representation of conductor product model. There are many kinds of conductors. The round wire concentric stranded hollow conductor is widely used in EHV and UHV, and the aluminium clad steel reinforced is the most common representative.

Under normal conditions, we observe that the aluminum strand is in a relaxed state. At this time, the force on the aluminum strand is indeed small. When the tension continues to increase, the steel core extends, and the aluminum strand is gradually tensioned and stressed. Under the condition of breaking, the force on the aluminum strand is not small and should not be underestimated.

It is worth mentioning that, for the sake of specification and practicality, the tensile breaking force of steel core or aluminum clad steel core is safe, which is specified as the stress at 1% elongation. In other words, when the steel core is broken, it shall be extended by at least 1%. According to the 400m span, when the conductor is to be broken, the steel core shall be extended by at least 4m. At this time, the aluminum strand has been strained. We made the conductor and ground wire crimping test piece, the aluminum strand played such an obvious lantern, and the tensile test was still qualified. This is basically the reason.