Geometric shape in walls of former university cut from concrete (7)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Geometric shape in walls of former university cut from concrete F <orme> R (“walls of” means first and last letters only) + ACT <u> AL (=real; “ university (=U) cut” means letter “u” is dropped); a fractal is an apparently irregular or chaotic geometric entity, much used in computer graphics