The minimum diameter of circular cofferdams composed of AzAUPU, GU and PUR steel sheet piles
. Since the minimum diameter also takes into account other factors such as soil type, pile length and depth of embedding, the data in the table are for reference only.
If the pre-bending pile is used, the cofferdam diameter can be made smaller. For a small cofferdam more favorable approach is in the piling before the steel piles in the field stitching into a circular, so that the entire circle of steel sheet piles is Closed, the piling hammer around the the circumference of sub-sub-steel sheet piles into. Large cofferdam is not suitable for this approach, so in the pile when the need to pay attention to ensure that the last one can close the plate pile from the the Design edge closer.
Circular cofferdam in the ring beam instead of the ordinary purlin and support it can leave more construction space, ring beam by the ring to the extrusion force, the axial load can be calculated using the following formula: axial load (n) = purlin Load N / m × radius of cofferdam (m)
In this case.
Ring beam can be steel ring beam can also be reinforced concrete ring beam. For the steel ring beam, a professional maker can be large-scale H-shaped steel and rolled into a required radius of the design to consider ring beam stiffness can be timoshenko Formula, in addition, should also take into account the flange may occur local instability.
In this case.
The internal fill double wall cofferdam and the grid type cofferdam fill the cofferdam is the gravity type support structure, may be both sides parallel double wall cofferdam, the cap type steel sheet piles fence manufacturer may also be the lattice cofferdam. The stability of the two Cofferdams depends on the characteristics of the fillers, the subsoil, and the inlet of the steel docks to form the dry construction site and also the layout and type of the steel sheet piles. This cofferdam is often used for temporary closure can be used for artificial Island walls, pier walls and other permanent structures.