There are a lot of reasons why you see pieces of tire on the side of the road, but most of them are caused by heat. When a tire is traveling down the road, the sidewalls are flexing which ultimately creates heat. If the air pressure inside the tire is enough to carry the load of the vehicle and it’s contents, then the heat created by the flexing sidewalls is minimal and does not damage the tire. However, when the air pressure inside the tire is not enough to carry the load, the sidewalls flex to a much higher degree, which creates additional heat. If the heat is allowed to build up over a long enough time, the bonds between the plies and rubber components start to break down. Eventually the stress becomes too great and the tire experiences what most people call a “blow out”.
But tires can also fail as the result of road hazards such as pot-holes, curbs and surface debris. The simple answer to the problem is to avoid running over hazards that might damage a tire, but that is often unavoidable. The best practice is to visually inspect the sidewall after hitting a pot-hole or curb to look for any bulges. If a sidewall bulge is found, the tire must be replaced. After running over road debris, drivers should check the sidewalls and tread for any puncturing objects or damage that exposes ply material. If steel or fabric plies are visible, the tire must be replaced.
Almost all of the tire debris on our nation’s roads and highways could be avoided if drivers paid attention to the inflation pressure in their tires. The over-flexing that results from underinflation allows incredible amounts of heat to build up in the tire until it becomes too much for the components to stay together. Regular air pressure maintenance is the best insurance to prevent a “blow out” so it should be checked at least once a month as well as before a long trip.