2.1 INTRODUCTION

Earth retaining walls used for many waterfront structures are generally made from connected or semi-connected sheet piles. An advantage of sheet pile wall construction is that dewatering is not required during construction. Sheet piles can be made from wood, precast concrete, or steel.

Wooden sheet piles are generally used for small or temporary structures. Figure 2.1 shows the sections of some typical wooden sheet piles. Figure 2.1a shows the sections of wooden planks which are driven side by side, and Fig. 2.1b shows the sections of splined wooden sheet piles. For this type of sheet pile wall construction, metal splines are driven into the grooves of adjacent sheetings to hold them together after they are driven. Wooden sheet piles may be 2 3 in. (50 75 mm) thick and 12 16 in. (300 400 mm) wide.

Figure 2.1: Wooden sheet piles; (a) Wooden planks driven side by side; (b) Wooden plank with splines.

Figure 2.2 shows the section and elevation of a precast concrete sheet pile generally used for construction. These sheet piles are 5 10 in. (125 250 mm) thick and 20 40 in. (500 1000 mm) wide. After the sheet piles are driven, cement grout is placed in the grooves between two adjacent sheet piles.

Figure 2.2: Precast concrete sheet pile.

In most permanent structures, steel sheet piles are used. Steel sheet piles may generally have a Z-type section, a U-type section (or low or high arch type section), or a straight web-type section, as shown in Fig.