I haven't the faintest idea of what these bars could mean. They're thick and mostly horizontal with a slight tilt. Some sort of run perhaps? How do you effect the dynamics/notes these bars are referring to?
EDIT: For reference, this specific example is from Offenbach's Galop infernal, but I've seen it in other pieces I've played and never quite knew what to make of it.
It's a tremolo. There are two types of tremolos. One between two different notes like in your example above and a second with the bars going though the stem of the note.
In your case, it is like a trill where you go back and forth pattern them in that patter at at a speed related to the bars connecting the two notes. So the two bars in the first measure would equate to 16th note speed and the three bars in the second measure would equate to 32nd note speed. The idea is that when the tremolo is finished you have played both notes the duration notated, but alternated at a certaint speed based on the number of bars. Here is the link I used to confirm the notation:http://en.wikipedia.org/wiki/Tremolo#Notation
I would listen to a few examples so you get a good idea of what they are before you dive right into them. Hope this helps.
This is tremolo notation. The beams indicate the speed of the tremolo.
In the first bar, you should alternate between the D-F# chord and the A in 16th notes.
In the second bar, you should alternate between the two sets of notes in 32nd notes technically, or "as fast as possible" if 32nds are infeasible.
