| A load-impulse (P-I) diagram is a useful tool in preliminary strength design and damage assessment. Current approaches to derive P-I diagrams are primarily based on numerical dynamic analyses of the structural system. Further, there are no general energy based solutions that define P-I relationships, and very little has been done to address energy flow as a basis for P-I diagrams. Since the behavior of a structural member is governed by the amount and rate of external energy input and its ability to dissipate energy, defining energy flow relationships will characterize the entire domain of structural responses and corresponding damage.;This research presents a comprehensive energy flow approach to enable one to define the entire P-I domain. An energy based P-I diagram is developed, and its analytical solutions for a linear elastic system under rectangular and triangular load pulses are derived and compared with numerical method. In addition, an energy based estimation for predicting the peak response of a structural element under impact is also proposed. The applications of these approaches are illustrated, and the results are validated using test data and numerical tools, such as DSAS and ABAQUS/Explicit. |
