Server crash 'caus Couldn't load structure minecraft:ruin/big_brick_8 +/big_cracked_8 +/big_brick_8

Server crash if load

• structure minecraft:ruin/big_brick_8
• structure minecraft:ruin/big_cracked_8
• load structure minecraft:ruin/big_mossy_8

What I expected to happen was...:
normal game play in a new world

What actually happened was...:
Server crash if he have to load the blocks.
World and Server was complete clean start witch SnapShot 18w20a

Steps to Reproduce:
1. Just fly around and wait for the blocks to load.