block up vs blockade

block up is not a noun while blockade is a noun.

Word	Noun	Adjective	Verb	Adverb
block up	No	No	Yes	No
blockade	Yes	No	Yes	No

As verbs, block up and blockade are synonyms defined as:

Other synonyms of block up include bar, barricade, block, block off, stop.

block up (noun)	blockade (noun)
	a war measure that isolates some area of importance to the enemy
	prevents access or progress

block up (verb)	blockade (verb)
render unsuitable for passage	impose a blockade on
	obstruct access to
	render unsuitable for passage
	hinder or prevent the progress or accomplishment of