Specifcations
Section 4165. Timber Piles.
4165.01 DESCRIPTION.
Timber piles shall be round sections of the trunks of trees trimmed, peeled, and with or without preservative treatment. They shall meet the requirements for the class of piles specified in the contract documents.
Inspection arrangements shall be in accordance with Materials I,M. 462. The cost of inspection shall be included in the unit price bid for the material specified.
4165.02 CLASSIFICATION.
Piles shall be classified as follows, according to the use for which they are intended:
A. Untreated Timber Piles.
Untreated timber piles may be used for falsework or temporary construction.
B. Treated Timber Foundation Piles.
Treated timber foundation piles will be used for permanent foundations and for permanent wood substructures above groundwater level, unless treated timber trestle piles are specified in the contract documents.
C. Treated Timber Trestle Piles.
Treated timber trestle piles shall be used for permanent wood trestle and may be specified for piers and abutments of substructures, where the more restrictive straightness requirements of this class are desirable.
4165.03 UNTREATED TIMBER PILES.
Timber piles to be used where preservative treatment is not required may be White Oak, Burr Oak, Cypress,
Tamarack, Douglas Fir, Southern Pine, or other wood which will satisfactorily withstand driving. They shall meet the following requirements:
A. General Quality.
Piles shall be cut above the ground swell from live, sound, solid trees and shall have a gradual taper from point of butt measurement to tip. They shall be free from ring shakes, decay or rot, unsound knots, soft red heart, splits, and other defects which will impair their strength or durability. Cypress piles showing "peck" more than a single spot equal to 3% of the area of the end will not be accepted. Piles shall be free from excessive checks at the tip which would cause splits in driving.
B. Knots.
Piles shall have no unsound knots. Sound knots will be permitted, provided they are not in clusters, and provided the diameter of any single knot is not larger than 4 inches (100 mm) or 30% the diameter of the pile at the point where it occurs, whichever is smaller. The sum of diameters of all knots in any 1 foot (0.3 m) length of pile shall not exceed 2 times the diameter of the allowable knot. Diameters of knots shall be measured in a plane perpendicular to the long axis of the pile.
C. Rate of Growth.
When measured at the butt, over the outer 3 inches (75 mm) of a radial line from the pith, piles shall show not less than the number of annual rings and percentage of summerwood specified below for the respective species:
SUMMERWOOD | ||
Species | Rings per Inch (25 mm) | Minimum |
Douglas Fir Douglas Fir Southern Pine Southern Pine | More than 5 5 or less More than 5 3 to 5 | 30% 30% |
When the number of annual rings varies along different radii, the average of two or more measurements along representative radii shall be used.
D. Holes.
Holes shall be permitted if less than 1/2 inch (13 mm) in average diameter, if they do not penetrate more than 20% the diameter at the point where they occur, and if the sum of the average diameters of all holes in any square foot (0.1 m2) of pile surface does not exceed 1 1/2 inches (40 mm).
E. Twist of Grain.
Piles shall be free of twist in grain exceeding 50% the average circumference in a 20 foot (6 m) length.
F. Length.
Piles shall be furnished in the length specified in the contract documents or as directed by the Engineer. A variation of 6 inches (150 mm) in length will be permitted, but the average length for piles of any one lot shall be at least equal to the specified length.
G. Straightness.
Piles shall be free from sweep in two planes (double sweep). They shall be free of short crooks. In measuring for short crooks in any 5 foot (1.5m) section, the distance from the center of the pile at the point of greatest deviation to a line stretched from the center of the pile above the bend to the center of the pile below the bend shall not exceed 4% of the length of the bend, or a maximum of 2 1/2 inches (65 mm). In sweep in one direction and in one plane, the center of the pile shall not deviate from a straight line connecting the center of butt with the center of the tip by more than 1.0% of the length of the pile, or 4 inches (100 mm), whichever is greater, with a maximum deviation of 6 inches (150 m) for lengths over 50 feet (15 m). Piles with sweep in two directions in the same plane (reverse sweep) may be accepted, provided the reversal is within the middle half of the length, and provided the deviation of the center of the pile from a straight line connecting the center of the butt with the center of the tip does not exceed 2 inches (50 mm). Within 25% of the length of the pile, but not less than 10 feet (3 m) nearest the tip, the center of the pile shall not deviate more than 1 inch (25 mm) from a line drawn from the center of the pile above this length to the center of the tip.
H. Dimensions.
At least 95% of the pieces of one length in any one shipment shall conform to the following dimensions for the species of wood specified. The remaining 5% of the pieces may be deficient in diameter at tip or 3 feet (1 m) from butt by not more than 1/2 inch (13 mm).
Win. Diameter 3 Feet (1 m) From Butt | Min. Tip Diameter inches (mm) | ||
Length feet (m) | Fir & Pine inches (mm) | Other Species inches (mm) | |
20 and shorter (6.0) | 10* (250*) | 10* (250*) | 8 (200) |
25 to 30 (7.5 to 9.5) | 11 (275) | 11 (275) | 8 (200) |
35(10.5) | 12 (300) | 13 (325) | .8(200) |
40 (12.0) | 12(300) | 13 (325) | 7(175) |
40 to 60 (13.5 to 18.0 | 1 3 (325) | 14(350) | 7(175) |
over 60 (18.0) | 13(325) | 14(350) | 6(150) |
'Measured at the butt. | |||
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