Shattered Glass Rainbow

I have created a rainbow by blending a group of lines. I want to make the end of the rainbow look like it has shattered. I have viewed many tutorials on how to create a broken glass effect with words by typing the word, outlining it to create a shape and then dividing the path behind glass shard shapes of the word but I can not figure out how to do the same with the rainbow made from a series of parallel blended lines. I believe it has something to do with the fact that the lines are not a shape. I tried to convert the lines into shapes but illustrator are not allowing for it. Any guidance would be greatly appreciated. Thanks