p.
  Some Constraints can receive options that include some sort of strength value.
  If a Simulation reaches a point where the Constraint is acting beyond its strength,
  it will destroy itself to create realistic deformations and structural behavior.

p.
  RopeConstraints can have a tensile strength. Here, we specify that once the
  Constraint stretches to 3x its original length, it should break:

pre.CodeBlock.
  this.add(Newton.RopeConstraint(prev, current, {
      length: segmentLength,
      stiffness: 0.9,         // slightly springy
      strength: 3             // break when stretched to 3x length
  } ));