(d) Complete all bolted connections and install tie rods. 



(e) Place the backfill; where passive resistance anchorage 

 systems are used, be certain to place fill over the 

 anchors before backfilling behind the sheet-pile wall. 



Establish accurate survey lines as a control for the construction 

 of waterfront and shore protection structures, and anchorage systems. 

 Exercise care in locating positions of round piles and posts that sup- 

 port horizontal timbers that will be used as driving guides for sheet 

 piles. In all cases, use a driving guide for sheet piles, preferably 

 the permanent horizontal wale that is attached to the vertical round 

 piling or posts (Figures 1, 2, and 3). 



It is particularly important to drive the first few sheet piles 

 accurately vertical in all directions. The wall must be plumb and 

 the sheet piles must not be inclined within the plane of the wall. One 

 of the common problems facing piling contractors is "creep," the ten- 

 dency for successive sheet piles to lean more and more in the direction 

 of construction of the wall. The wall can be perfectly plumb, yet piles 

 can lean; this error in alinement tends to accumulate and, if left 

 uncorrected, can create considerable difficulties in driving successive 

 piles. Chellis (1961) has a discussion of this situation and how to 

 correct it. As sheet-pile driving proceeds, place the tongue of each 

 new sheet in the forward position and the groove in tight contact with 

 the tongue of the sheet previously driven. Keep the joints between 

 piles as tight as practicable. Remember that the maximum allowable 

 opening at joints is one-half inch for splined and Wakefield piling, 

 and one-fourth inch for tongue and groove piling. If wider joints 

 appear after the sheet piles have been spiked to the outer wale, cover 

 with treated timber lath to prevent the backfill material from gradually 

 filtering through the cracks and being lost. 



Wherever passive-resistance anchorage systems are used the anchor- 

 age must be well covered with a mound of earth before backfill material 

 is deposited to any appreciable depth against the piling. Otherwise, 

 the pressures generated by the backfill may disrupt the sheet piling 

 and the anchorage system. 



Use a predominately granular material for backfill adjacent to the 

 sheet piling and over the anchorage system. Shoreward of the anchorage, 

 a poorer quality filling material may be used unless it is objectionable 

 from the standpoint of foundation support for shore structures. 



If the hydraulic method is used for backfilling, provide suffi- 

 cient drainage to permit rapid escape of water at the ends of the con- 

 struction area, both to prevent formation of pools and to maintain as 

 low a free water level in the backfill as possible. Although the 

 bulkhead is designed to hold earth, it may not be designed to resist 

 water pressures that can be generated during hydraulic filling. 



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