Columbia subject headings:
Harvard subject headings:
Bridges--Foundations and piers
Bridges--Foundations and piers--Congresses.
Foundations--Congresses.
Foundations.
Piling (Civil engineering)
Piling (Civil engineering)--Congresses
Princeton subject headings:
Bridges--Foundations and piers--Congresses.
Foundations--Congresses.
Piling (Civil engineering)--Congresses.