Effect of Suspension Clamp Types on the Dynamic Bending Stress of All Aluminium Alloy 1120 Overhead Conductors

Determination of the bending stress is one of the important factors for the design or fatigue assessment of transmission power lines. Researchers and designers calculate the bending stress of overhead conductors by using the Poffenberger-Swart (P-S) formula, which was established for the conductor/metal suspension clamp system. This publication presents experimental work on the effect of different configurations of suspension clamps on the dynamic bending stress that causes fatigue in the conductor. For each type of clamp configuration, specific points of the conductors were instrumented with strain gauges for the measurement of bending strain. The prediction of bending stress by the P-S formula presented errors of up to 140% for clamp different from the one established during the formulation. A better correlation with experimental data was obtained by adjusting considering an effective length of the lever arm for elastomeric clamps.