http://www.cnn.com/2006/US/10/31/missed.runway.ap/index.html

I thought the basic design driver for a runway is the aircraft landing impact it will take. Probably more critical because it's usually easier to make a runway longer than stronger.

1) Are taxiways usually built strong enough to take a landing? Seems like overkill.

2) What is the basis of numbering runways? An aerial view of Newark Liberty shows the main runways are 4 in one direction and 22 in the other. Obviously not numbered for the heading or bearing.

Thanks,
Sixto
93 300SD