lava 3d printer

rocks could be crushed into gravel or sand 

and then the gravel could be superheated 

with electro air plasma torches 

so that the gravel melts into lava 

and then a 3d printer could 3d print the lava 

into bridge pillars underwater in the sea 

the cold seawater will immediately cool down the 3d printed lava 

since the 3d print stream will probably only be a few centimeters thick 

that could make it cheaper and quicker 

to construct bridge pillars underwater 

a lava 3d printer technology demonstrator 

could quickly be produced 

since the technologies involved 

have been used in various industries for a long time 

and according to media there is a shortage of cement and concrete 

but there will never be a shortage of rocks 

and enclosures underwater to fill with concrete will not be needed 

since the lava is 3d printed directly in seawater 

wich will save a lot of time 

since enclosure will not have to be constructed underwater

and that would enable more ambitious bridge projects 

to be constructed more cheaply and quickly 

such as 

the gibraltar bridge between marocco and spain 

and the kvarken bridge between sweden and finland 

and/or the sweden - åland - finland bridge 

and the south east asian bridges