Tiled swimming pool cracked after emptying?

Answer 1

Emptying a pool is a risky procedure, but must be done in the case of replastering or restoration. The weight of the water stabilizes the structure of the pool against the substrate (soil/gravel). Once you remove the water, you have nothing to stabilize the pool. This is particularly dangerous if the ground is wet, or is flooded by recent rains. In this case, the pool can "float" and cause cracking of the structure.

It is likely that your pool shifted a little once the water was out. You need a professional to look over the structure and determine if there are other structural faults or worse--leaks.