Abstract:

ESDU 09003 is the third in a series that deals with the dynamic characteristics of tension/compression springs of cylindrical helical form. The present Item extends the scope of the earlier Items to impact loading.

In the first part of this Item the classical theory of impact is used to investigate:

• an impact load applied to the free end of a spring,
• an impact load applied to a spring-mass system, examining both non-elastic and elastic systems
• an impact load applied to a two-degree-of-freedom system.

The second part of the Item examines the impact load applied to the free end of an elastic rod, in which the rod with the same elastic properties as the helical spring is used as an "equivalent rod" representing the spring. Discontinuous functions are used to represent the motion of a wave-front of elastic deformations which travel along the rod at a finite velocity.