Concrete Slump Cone

Print out of ASA for UV resistance as this will most likely be used outside. Other rigid filaments such as PETG, ABS, PLA etc might also be acceptable. Avoid TPE or TPU that will flex too much.
 

If your printer isn't tall enough, cut into two parts with mating connectors in your slicer. After printing both parts, use heavy duty tape on outside, glue inside joint.

Finally sand any rough edges on inside before using.
 

See https://en.wikipedia.org/wiki/Concrete_slump_test
 

Editable model is available for free in onshape