瓦解 is read as がかい (gakai) and means collapse.
がかい
gakai
どほうがかい
complete collapse
がれき
trash
かわら
roof tile
わげ
court-mediated settlement
けんかい
opinion
りかい
sympathy
りょうかい
OK
ぶんかい
factorization
べんかい
explanation (e.g. for one's actions)
せいかい
correct answer
なんかい
difficult to understand
ごかい
misunderstanding