The Mystery of Trencadis

While studying interior design in college I saw images of crazy benches by some guy by the name of Gaudi.  I scoffed.  Benches, facades of buildings, and chimneys covered with broken pieces of tiles and pottery seemed like child's play to me.   I mean, who could even take this guy seriously.  Ironically, over the last few years I have become a bit obsessed with the genius of this man and particularly his use of broken tiles called "trencadis". 

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Architectural features similar to these chimneys  jut out from the rooftops of Gaudi's Barcelona projects.  Like a child breaking out into a spontaneous dance, this colorful and unconventional style tends to bring a smile to the face of even the most cynical onlooker
At first glance it appears to simply be surface decoration.  With symbolism obviously and  inextricably designed into projects like his famous "Sagrada Familia" and Casa Batllo,  I must ask the questions...Is there some mysterious symbolism associated with the use of trencadis?  
I have my ideas...but what do you think?  Is the trencadis symbolic of anything  and if so what?  

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