Tire Burst Phenomenon and Rupture of a Typical Truck Tire Bead Design

Even though relatively rare, the tire failures are very dangerous. An example of tire failure is over-pressurization that usually occurs during inflation of the tire, when the latter is inflated well beyond the pressure recommended by the tire manufacturer. When inflating tires, personnel assigned to vehicle repair and maintenance are likely to suffer severe injuries if several safety rules are ignored. Experimental data on tire burst is somewhat rare in the open literature. In order to determine the strength limits of a typical truck tire and describe the mechanism of the tire burst phenomenon, a hydrostatic burst test was first conducted on an 11R22.5 tire. From this test, tire burst pressure was determined. Over pressurizing the tire results in a high tension in the steel wire beads. As the total strain this kind of steel can withstand is rather low, their fracture will be source of the general failure. Then, an x-ray inspection and microscopic analysis were performed on the tire beads in order to characterize their behavior and failure. Furthermore, a finite element analysis was also conducted using material properties from the available literature to determine the inflation pressure resulting in failure of a new tire. The model was able to well predict the tire burst pressure by identifying the pressure at which the maximal plastic strain of steel bead wires is reached. Finally, the various tests and finite element analysis allowed to understand why, where, when, and how a truck tire fails when over pressurized.