You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
37 lines
2.4 KiB
37 lines
2.4 KiB
\chapter{Introduction}
|
|
|
|
There are many cases where the description of rigid body motion
|
|
during an impact event is desired. Two examples are the response of a
|
|
radioactive materials transportation container to the regulatory
|
|
30-foot drop event and the effects of certain deployment options on
|
|
various weapon components. Rigid body motion effects are of primary
|
|
importance for eccentric impact orientations in which a vector normal
|
|
to the impact surface at the point of impact does not pass through the
|
|
center of gravity of the body. In this impact orientation, the body
|
|
will tend to rotate about the impact point which will possibly result
|
|
in a secondary impact at the opposite end of the body. This sequence
|
|
of a primary impact followed by a secondary impact at the opposite end
|
|
of the body is commonly called {\em slapdown}. In many cases, the
|
|
secondary slapdown impact can occur at a higher velocity and be more
|
|
damaging than the primary impact. A computer program called \SLAP\ has
|
|
been written to approximate the slapdown behavior of deformable bodies
|
|
and to aid in the investigation of eccentric impact events.
|
|
|
|
In this report, the basic analytical approach to the problem of shallow angle
|
|
slapdown is shown in Chapter~2. The numerical implementation of the solution
|
|
of the nonlinear equations of motion is developed in Chapter~3. Applications
|
|
to a variety of generic slapdown issues are presented in Chapters~4--6. These
|
|
generic issues include the effects of geometric variables, initial impact
|
|
behavior, and friction on the slapdown severity. Chapter~7 details the proper
|
|
procedures to follow for extrapolation of scale model test results to the
|
|
full-scale response. A user's manual detailing the input required and the
|
|
output from \SLAP\ is presented in Appendix~A. The analytical results from
|
|
\SLAP\ are compared to the experimental results from a test program on a
|
|
half-scale model of an actual radioactive materials transportation container in
|
|
Appendix~B, and Appendix~C is a description of the \EXO\ database format.
|
|
|
|
The primary motivation for the development of this capability was to address
|
|
the behavior of radioactive materials transportation containers during shallow
|
|
angle slapdown impact events. Therefore, the applications presented reflect
|
|
container geometries and impact limiter behavior typical of this field. This
|
|
should not in any way be considered the exclusive use of the computer program.
|
|
|