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Fruitbodies of Agaricus bitorquis ( The Sidewalk Mushroom) pushing up the hardtop on a driveway. 

The cause of this event is probably improper preparation at the time of construction.  Organic debris was trapped under the hardtop and spores of the fungus were either present or percolated to the site in water suspension.   Eventually the organic source (cellulose and lignified cellulose of plant debris) would be colonized completely and the fungus   produced the fruitbodies that  pushed up the hardtop.  Fungi have been known to push up paving stones and that is a much more impressibe 'trick'!

It is also possible that a tree died or was cut down near the driveway.  The roots under the driveway are then dead and would be a SUBSTANTIAL food source for fungi and that could be a REAL problem.