"How SAFE are radioactive material transportation packages?"



How are packages certified?
What are full-scale tests?
What are scale-model tests?
What is computer analysis?
Package Certification Using Computer Analysis
Engineering Principles Established by Three Early Scientists
Engineering Principles Applied to Ancient Structures
Description of Computer Model in Computer Analysis
Engineered Structures Built WITHOUT the Use of Computer Analysis
Structures Analyzed WITH the Use of Computer Analysis
What are examples of severe testing?
How do the certification tests compare to real-life accidents?
Demonstrating target hardness.
Describing Computer Analysis
Computer Analysis Single Element Action - Reaction Tension (Tensile) Benchmark

Click to view picture

Click to view picture
being dev.
Click to view picture
being dev.
Click to view picture

Click to view picture
Computer analysis is used to solve a series of complex mathematical equations that describe the behavior of the structure being analyzed. The behavior of the entire structure is too complicated to describe mathematically, so it is divided into smaller segments that have well defined behavior. Each of these segments influences the response of other segments in the structure. The response of the entire structure is determined by combining the responses of each segment. The way that each segment behaves and how they interact is developed from physical laws, such as Hooke's Law, and material data obtained from tests. Validation of computer analysis is done by comparing the results for complex structures to test results in a process known as benchmarking.
Computer Analysis Fundamentals come from
Engineering, Science, and Mathematics
Mechanics Statics Deformable Body Mechanics

Click to view picture

Click to view picture

Click to view picture
The dynamic analysis used to determine the response of radioactive material packages is built upon Newton's Laws of Motion and the disciplines of statics, deformable body mechanics, dynamics, and continuum mechanics. Statics involves the study of rigid bodies that are in equilibrium with the forces acting on them.

The fundamental equations of statics are that the sum of forces acting on a body are equal to zero and the sum of the moments acting on a body are equal to zero. These can be expressed in orthogonal coordinates as:
Fx = 0 Fy = 0 Fz = 0
Mx = 0 My = 0 Mz = 0

For planar (flat) structures three of these equations drop out and we are left with:
Fx = 0 Fy = 0 M = 0

Deformable body mechanics involves the study of how forces acting on a body cause it to change size and/or shape.

The fundamental relationship in deformable body mechanics is Hooke's Law, which in its simplest form is: [stress] = E[strain]

Another basic principle of deformable body mechanics is the continuity of displacements: if a point within a body moves a certain amount, the amount of motion is the same for all parts of the body connected to that point.

The way a given material responds to forces is a property of the material. Material properties that are often measured include:

  • Yield stress - the amount of stress that can be applied to a material without causing the material to permanently change shape.
  • Ultimate stress - the amount of stress that can be applied to a material without causing it to break.
  • Young's modulus - the value of E in Hooke's Law.
  • Poisson's ratio - a measure of the change in volume of a material under stress.
  • Modulus of thermal expansion - the amount a material expands when it is heated.

DOE | NTP Headquarters | NTP Albuquerque Operations
Sandia National Laboratories | Nuclear Energy & Fuel Cucle Programs
Acknowledgment and Disclaimer