63falcondriver

A frozen brake would normally break free but in your case it didn't because there wasn't enough friction between the tire and the road due to snow/ice. If you're not expecting any above freezing temps, a hair dryer directed on the brakes to warm them up will do the trick. If you have drum brakes on the rear (mine does) pulling the tire off will give better access. Just warm up the drum above freezing and the ice will turn to water and the drum should be able to turn. By putting your parking brake on when the brakes were wet, it allowed the ice to "glue" the brake shoe to the drum interior. If you had a dry paved road, the friction between the tire and the road would likely be great enough to shear the icy bond. Once the car is driven, the heat generated by the brake linings on the brake drum will evaporate all the moisture unless you get a repeat of the unusual conditions.