System for protecting wooden structures against marine borer attack

摘要

879,521. Preserving timber piles. LIDDELL, O. E. Feb. 4, 1959, No. 3982/59. Class 68(2). A method of protecting timber from marine borer attack by limiting the circulation of water around the timber to a rate insufficient to maintain marine borer life within the vicinity of the timber, comprises enclosing the timber in a continuous sheath. Fig. 1 shows a pile 22 being encased by a sheet B cut off a roll of p.v.c., rubber, neoprene or woven fabric and which finally extends from above the water level to about two feet down into the sea bed. On each edge of the sheet is a bead 28 so that the two edges of the sheet can be gripped by a corrosion-resisting metal tubular member 30 with a longitudinal slot which is an easy fit over the double sheet thickness but is less in width than the combined thickness of the double bead. A space 38 is cleared by jetting, the sheath is slid down the pile and tightened on to the pile by rolling the tubular member, in the direction of the arrow in Fig. 4, to take up any slack. The member 30 is fixed in position by a pin 40 (Fig. 5 not shown). In a modification the sheet is cut to length before fitting to the pile and has a'rigid reinforcement of semi-circular cross-section attached to each long edge. The ends of the reinforcements are fitted into sockets at top and bottom so that the edges of the sheets can be rolled round as before to tighten the sheath, and pinned to prevent further movement. An additional piece is also provided on the lower end of the sheath to wrap round the pile and protect the lower end of the pile and reinforcing members.