7-45 Sectio N 709 – Lumbe R and Timber
709.01 STRUCTURA L LUMBE R AND TIMBER . Structural lumber and timber shall conform to the species and stress -grades specified in the Contract and shall be acceptable to the Engineer.
a.Grading . Structural lumber and timber shall be graded in accordance with AASHTO M 168 . Lumber ordered in multiple lengths shall be graded after having been cut to length.
b.Moisture Content .
1.Untreated Lumber and Timber . The maximum moisture content of untreated lumber and timber material being incorporated into the work shall be 19%.
2.Treated Lumber and Timber . The maximum moisture content of treated lumber and timber material prior to treatment shall be 19%. M aterial treated with water -borne preservatives in accordance with AWPA standards shall be dried after treatment to a moisture content not exceeding 19% and shall be maintained at a moisture content of 19% or less until it is incorporated into the work.
c.Minimum Stress Requirements . Unless otherwise specified in the Contract, lumber and timber shall meet the allowable unit stress requirements for No. 1 Grade or better material as specified in the AASHTO LRFD Bridge Design Specifications .
d.Lumber Dimens ions.
1.Full-Sawn Lumber . Minimum full -sawn lumber sizes are nominal dimension sawn sizes after seasoning. Pieces shall be sawn to obtain the full nominal dimensions specified with only occasional slight variation permitted. Thickness and width dimension s are somewhat variable depending upon the sawmill equipment used.
2.Rough -Sawn Lumber . Rough dry -sized lumber is minimally 1/8 inch larger in each dimension than standard (seasoned) dressed -sized lumber. Thickness and width dimensions are somewhat varia ble depending upon the sawmill equipment used.
3.Dressed Lumber . Dressed lumber sizes are the finished planed dimensions of material after seasoning. Minimum net finished dimensions for dressed lumber shall be 1/2 inch less than the nominal dimension, except that the minimum net width of dressed lumber exceeding 6 inches shall be 3/4 inch less than the nominal dimension.
7-46 (e) Lumber Finish . Lumber finishes shall be as specified per the requirements of AASHTO M 168 for
manufacturing classifications (e.g. rough lumber or dressed lumber) .
f.Soundness . Lumber material shall be sound and free from any incipient or advanced form of decay.
g.Preservative Treatment . Preservative treatment of lumber and timber materials shall conform to the requirements of Subsection 726.01 and AWPA Standard U1 .
h.Miscellaneous Hardware, Shapes, and Fabricated Materials .
1.Structural steel shapes and metal fa bricated materials shall conform to the requirements of the Contract and the material requirements specified in Section 714 and Section 715 .
2.Unless otherwise specified, bolts, studs, threaded rods, nuts, and washers shall conform to the requirements of ASTM A307, Grade A. Carbon steel nuts , unless otherwise specified , shall conform to the requirements of ASTM A563 .
3.Nails and spikes shall co nform to the requirements of ASTM F1667 .
4.Lag screws shall be of low to medium carbon steel and shall be of good commercial quality.
5.Unless otherwise specified, all steel hardware and fabricated materials shall be galvanized in accordance with AASHT O M 111 or AASHTO M 232 , as applicable. 709.0 2 NONSTRUCTURA L LUMBER . Material furnished under this subsection shall be for non -load– carrying structural applications with a maximum nominal thickness of 2 inches (e.g. boarding, siding, trim, etc.). Lumber shall be seasoned or kiln dried spruce, eastern white pine, eastern hemlock, southern pine, or western fir, u nless otherwise specified in the Contract.
a.Grade . The grade classification of yard lumber, whether common or select , shall be as specified in the Contract. Structural lumber meeting the requirements of Subsection 709.01 and nominal 2 - inch thickness may b e used for nonstructural lumber applications. Except with the written permission of the Engineer, lumber which has not been grade classified or stress -graded shall not be used for nonstructural lumber.
b.Moisture Content . The moisture content of nonstruc tural lumber shall be as specified in Subsection 709.01(b) .
7-47 (c) Dimensions .
1.Full-Sawn . When required in the Contract, lumber shall be furnished to the minimum full - sawn (nominal) dimensions specified.
2.Dressed . Unless otherwise specified, all lumber shall be surfaced four sides (S4S).
d.Finish . Rough lumber or dressed lumber shall b e finished per the requirements of AASHTO M 168 manufacturing classifications.
e.Soundness . Nonstructural lumber shall be sound and free from any incipient or advance form of decay.
f.Preservative Treatment . Preservative treatment of lumber shall conform to the requirements of Subsection 726.01 and AWPA Standard U1 .
g.Hardware, Shapes, and Fabricated Materials . Hardware, shapes, and fabricated materials shall be as specified in Subsection 709.01(h) . 709.0 3 STRUCTURA L GLUE D LAMINATE D TIMBER .
a.Material . Unless otherwise specified, structural glued laminated (glulam) timber shall be fabricated from southern pine, coastal Douglas fir, western hemlock, or western larch and shall meet the requirements of AASHTO LRFD Bridge Construction Specifications, Section 16 . Adhesives used in the lamination process shall be for wet -use conforming to the requir ements of ASTM D2559 and shall comply with all other requirements of ANSI/AITC A190.1 . Unless otherwise specified, the appearance grade of the finished glulam products shall be industrial.
b.Seasoning . Unless otherwise specified, all material shall have a moisture content not exceeding 16% at the time of gluing laminations.
c.Preservativ e Treatment . Unless otherwise specified, all glued laminated timber shall be treated in accordance with AWPA Standard U1 . Also, unless otherwise specified, all material shall be shop - fabricated prior to treatment. Any field treatment required by the Engine er shall be performed in accordance with AWPA Standard M4 .
7-48 (d) Miscellaneous Hardware, Shapes, and Fabricated Materials .
1.Structural steel shapes and metal fabricated materials shall conform to the requirements of the Contract and the material requirements specified in Section 714 and Section 715 .
2.Unless otherwise specified, bolts, studs, threaded rods, nuts, and washers shall conform to the requirements of ASTM A307, Grade A. Stainless steel fasteners shall conform to the requirements of ASTM F593, Alloy Group 1, Condition AF, Alloy 304 and its supplementary requirements for S5, with nuts conforming to the requirements of ASTM F594 .
3.All welding shall conform to the requirements of Subsection 506.10 .
4.Nails and spikes shall conform to the requirements of ASTM F1667 .
5.Lag screws shall be of low to medium carbon steel and shall be of good commercial quality.
6.Unless otherwise specified, all steel hardware and fabricated materials shall be galvanized in accordance with AASHTO M 111 or AASHTO M 232 , whichever is applicable.
e.Dimensions . The designated dimensions for glued laminated timber shall be taken as the actual net dimensions.
f.Handling . Glued laminated timber shall be carefully handled to avoid damaging the edges and surfaces. The handling, transit, and erection procedures shall m eet the requirements of AITC 111 . 709.04 RAILROAD TIES .
a.General Requirements .
1.Preservative Treatment . Railroad ties shall be preserved in accordance with AREMA Chapter 30, Section 3.6 ; AREMA Chapter 30, Section 3.7 ; and one of the following:
a.AWPA P1/P13
b.AWPA P2
c.AWPA P3
d.AWPA P60
7-49 (2) Field -Applied Preservative Treatment . Field -applied preservative treatment shall meet the
requirements of Subsection 726.01 .
3.Anti-Splitting Devices . Railroad ties shall be furnished with anti -splitting devices in accordance with AREMA Chapter 30, Section 3.1.6 and AREMA Chapter 30, Secti on 3.1.7 .
b.Bridge Ties . Bridge ties shall be No. 1 Grade or better solid sawn oak in accordance with AREMA Chapter 7, Section 1.7 and meet the following requirements :
1.Surface . Bridge ties shall be surfaced two sides, top and bottom, and dapped (notched) for stringer flanges on the bottom side as shown on the Plans. The heartwood side shall be the bottom side for dapped ties.
2.Dimensions . Bridge tie dimension s shall be as show n on the Plans.
c.Cross Ties . Cross ties shall be solid sawn treated timber from mixed hardwoods, in accordance with AREMA Chapter 30, Section 3.1 .
1.Cross Ties, Type A . Type A cross ties shall be 6 -inch grade cross ties, 6 inches × 8 inches in cross section.
2.Cross Ties, Type B . Type B cross ties shall be 7 -inch grade cross ties, 7 inches × 9 inches in cross section.
d.Switch Ties . Switch ties shall be solid sawn treated timber from mixed hardwoods, in accordance with AREMA Chapter 30, Section 3. 2. Switch ties shall be 7 -inch grade switch ties, 7 inches × 9 inches in cross section.
e.Tie Plugging Material . Tie plugging material shall meet the requirements of AREMA Chapter 30, Section 3.1.5 . Liquid tie plug material shall be non-foaming, polymer -based synthetic polyurethane tie plugging compound.
7-50 Sectio N 710 – Culverts , Stor M Drains , and Sewe R Pipes , Nonmetal
710.0 1 REINFORCE D CONCRET E PIPE. Reinforced concrete pipe shall conform to the requirements of AASHTO M 170 with the following notes or exceptions:
a.Design Requirements . The circular reinforcement specified in AASHTO M 170, Table 3 for 24 - inch, Class III, Wall B pipe shall be 0.1 square inch per foot of pipe wall. Elliptical reinforcement shall not be used in circular pipes. All pipes 24 inches in diameter or smaller shall be of the bell -and-spigot type. Pipes larger than 24 inches in diameter may be either of the tongue -and-groove or bell -and-spigot types. 710.0 2 REINFORCE D CONCRET E PIPE END SECTIONS . Reinforced concrete pipe end sections shall conform to the requirements of Subsection 710.01 . Where two cages of reinforcement are required in accordance with AASHTO M 170 , they shall be placed in the barrel of the end section only. Reinforcement of the apron section shall be equal in area to the inner cage of the barrel reinforcement. 710.0 3 CORRUGATE D POLYETHYLEN E PIPE (CPEP) . CPEP shall be evaluated in accordance with the AASHTO Product Evaluation & Audit Solutions work plan for Evaluation of HDPE (High Density Polyethylene) Thermoplastic Drainage Pipe Manufacturers and in compliance with the AASHTO Product Evaluation & Audit Solutions audit program for thermoplastic pipe. CPEP shall be one of the products listed on the Agency’s Approved Products Li st for the respective material specification.
a.Corrugated Polyethylene Pipe, Unlined .
1.Small Diameter . CPEP, unlined, with a nominal diameter of 3 inches to 10 inches, inclusive, shall be in accordance with AASHTO M 252 , Type C.
2.Large Diameter . CPEP, unlined, with a nominal diameter of 12 inches to 60 inches, inclusive, shall be in accordance with AASHTO M 294 , Type C.
b.Corrugated Polyethylene Pipe, Smooth Lined .
1.Small Diameter . Smooth lined CPEP with a nominal diameter of 3 inches to 10 inches, inclusive, shall be in accordance with AASHTO M 252 , Type S.
2.Large Diameter . Smooth lined CPEP with a nomi nal diameter of 12 inches to 60 inches, inclusive, shall be in accordance with AASHTO M 294 , Type S.
c.Corrugated Polyethylene Pipe, Perforated . Perforated CPEP shall be in accordance with AASHTO M 252 , Type CP or Type SP. Large diameter CPEP may be made of virgin materials , recycled materials, or a blend of both in accordance with AASHTO M 294 .
Source: Vermont Standard Specifications for Construction, 2024 Edition. Pages 1197–1201 of 1,380.