crumple

verbs

fall apart
"the building crumbled after the explosion"; "Negotiations broke down"
break down, collapse, crumble, crumple, tumble
fold or collapse
"His knees buckled"
buckle, crumple
to gather something into small wrinkles or folds
"She puckered her lips"
cockle, crumple, knit, pucker, rumple
become wrinkled or crumpled or creased
"This fabric won't wrinkle"
crease, crinkle, crumple, rumple, wrinkle