Does the Sydney Harbour Bridge Sway Side to Side?

No. The Sydney Harbour Bridge is a steel arch bridge designed for rigidity and stability. Its massive arch (503 m span, 39,000 tonnes of steel) transfers loads directly into the sandstone foundations via huge bearings. It does not sway laterally under normal conditions.

It does expand/contract vertically up to 18 cm (7 in) due to temperature changes (hinged bearings accommodate this). Wind-induced oscillations are minimal and damped by the structure's mass and stiffness. The bridge is engineered for 100+ year storms and seismic loads.