Caissons MCQ Questions - Construction & Building Materials

Explanation: A caisson foundation also called as pier foundation is a watertight retaining structure used as a bridge pier, in the construction of a concrete dam, or for the repair of ships.

Explanation: It is a prefabricated hollow box or cylinder sunk into the ground to some desired depth and then filled with concrete thus forming a foundation.

Explanation: Caissons are drilled either to bedrock called rock caissons

Explanation: Floating caissons are also known as floating docks and are prefabricated boxes that have cylindrical cavities.

Explanation: All of the above are Advantages of Caissons.

Explanation: True, Lack of construction expertise disadvantages of caissons.

Explanation: The materials commonly employed for the construction of dike are earth, rock and sand bags. The dike are generally employed for a short duration, particularly to enable the construction of a more durable cofferdam behind them

Explanation: Rock dikes or Rock-fill cofferdams can be used for a depth of water up to about 3 metres and a suitable even in case of Swift water. The only disadvantage of this type of cofferdam is that it is not impervious.

Explanation: New segments of cast iron are bolted as the caisson sinks. Cast iron is unsuitable for pneumatic caissons as there is risk of failures due to tension developed by the compressed air. The cost also works out to be more in relation to steel or RCC.

Explanation: Cylinder is used when depth of water is more than 12 meters or when it becomes essential go deep to avoid exposure of foundations due to scouring action of flowing water. The cylinder is a light shell which invariably become part of the permanent structure.