Engineering and Construction

Combi-piles are another form of part-fabricated piling used to form walls for deep excavations. The wall is formed from alternating tubular and sheet piles as shown in Fig. 29.4. The number of sheets between the tubes varies dependent on the required section modulus. The tubular piles take vertical loads and stiffen the wall.

Tubular piles are available in a wide variety of sizes, and both Larssen and Frodingham sheet piles are suitable as infill piles.Appropriate clutches are welded to the walls of the tubes, and these provide the designer with simple corner details for many different wall angles. It is apparent that the clutch locking bar strips from U-section sheet piles (or Larssen sections) are more stable to weld onto the tubulars than those from Frodingham section sheet piles.

Fig. 29.4 Combi-piles