Double walled cofferdam is provided in such situations.
Double wall sheet pile cofferdam.
Double walled cofferdams are those in which two parallel rows of steel sheet piles are connected with means of a track or a plurality of steel enclosed purlin brackets.
A double wall sheet piling cofferdam comprises two straight parallel vertical walls of sheet piling tied to each other.
Where h is height of water.
Double wall sheet pile cofferdam higher than 7 5 feet should be strutted.
Double walled sheet pile cofferdams.
The gap between walls is filled with soil.
Double wall sheet piles this type of cofferdam is suitable when it is required to exclude water over 36 feet.
This consists of two straight parallel vertical wall of sheet piling tied to each other and the space between them filled with soil.
This type of cofferdam can be used in depth of water up to 12 m.
They are cofferdams comprising two parallel rows of sheet piles driven into the ground and connected together by a system of tie rods at one or more levels.
The gap between the two rows of steel sheet piles is generally filled with granular material such as gravel or gravel.
The width between the parallel piles is h 2 1 50 m.
This type of cofferdams if higher than 2 5 m should be strutted.
The space between the walls is generally filled with granular material such as sand gravel or broken rock.