Not only are we abusing our bridges with more traffic but also with increased wheel loading.

Although alloy wheels have helped slow the growth in 'unsprung' mass, the heavier tires we use on our SUVs and light trucks combined with heavier suspensions have more than overcome any 'alloy wheel' benefit.

Probably time to markedly increase our design criteria. We aren't driving 1966 Beetles anymore.

jm2cw ... pete