Pole vault poles break primarily due to exceeding their load capacity or succumbing to existing structural weaknesses. This can happen if a vaulter uses a pole that can't handle their weight, or if a crack or defect leads to structural failure. Understanding these main causes is crucial for vaulter safety.
Key Reasons for Pole Failure
Pole vaulting involves immense force and stress on the pole as it bends and recoils. Poles are engineered to withstand significant loads, but they have limits. When these limits are surpassed or the material is compromised, breakage can occur.
Using an Under-Rated Pole
One of the most common reasons a pole breaks is when a vaulter uses a pole designed for a lighter athlete or less force. Each pole is rated for a specific range of vaulter weights and grip heights.
- Weight Mismatch: If a vaulter's weight or the force they apply during the jump exceeds the pole's rating, the material is subjected to stress beyond its design limits. This excessive bending can lead to catastrophic failure.
- Over-Flexing: Attempting to gain more height by using a pole that flexes too easily for a vaulter's strength and weight can also cause over-bending and increase the risk of breakage.
Proper pole selection based on the vaulter's weight, speed, strength, and grip height is essential to prevent this type of failure.
Structural Issues and Defects
Even if the pole is correctly rated for the vaulter, internal or external damage can weaken its structure.
- Cracks and Imperfections: A crack, no matter how small, can propagate rapidly under the high stress of a vault, leading to sudden structural failure. These can be manufacturing defects or damage sustained during transport, handling, or previous use.
- Material Fatigue: Over time, repeated bending cycles can cause the pole's material (typically fiberglass or carbon fiber) to weaken, although this is less common with modern materials than immediate failure from overload or defect.
- Impact Damage: Dropping the pole or hitting it against hard surfaces can create weak points that might not be immediately visible but can cause failure during a vault.
Regular and thorough inspection of the pole for any signs of damage, such as cracks, splinters, or delamination, is a critical safety measure.
Preventing Pole Breakage
Ensuring vaulter safety and extending the life of a pole involves adherence to best practices:
- Always select a pole appropriate for the vaulter's specific characteristics and the intended vault.
- Inspect the pole thoroughly before every use. Look for any surface scratches, deep gouges, cracks, or other visible damage.
- Handle poles carefully during transport and storage to avoid impact damage.
- Store poles properly, typically horizontally on racks designed to support their full length.
By respecting the pole's limits and maintaining vigilance for structural integrity, the risk of breakage can be significantly reduced.
