A ______ caisson is open at top and closed at bottom.
A. Wells
B. Pneumatic caissons
C. Cylinders
D. Box caissons
I have been asked this question in an internship interview.
Query is from Classification of Caissons in chapter Deep Excavations, Pile Foundations and Caisson of Construction & Building Materials
Right choice is D. Box caissons
For explanation: Box Caisson is merely a variation of the Suspended type cofferdam. The box caissons may be built of reinforced concrete, steel or timber. Condition for box caisson is that the depth of water is about 6 meters to 8 meters.