362 ALASKA 2020 SECTION 635
635-1.01 DESCRIPTION. Furnish and install polystyrene insulation board where shown on the
Plans.
635-2.01 MATERIALS. Use materials that conform to the following:
1.Insulation Board. AASHTO M 2 30, Type VI, except that extrusion is not required, and the maximum water absorption is 0.3 percent by volume, as determined by ASTM C272. Insulation board must meet or exceed the minimum thickness called out in the plans, and have a 20- year warranted ther mal resistance (R -Value) @ 75°F of 4.5 per inch of thickness as determined by ASTM C177 or ASTM C518. The required thickness is shown on the Plans and is actual thickness, not nominal thickness.
2.Sand Blanket . Subsection 703- 2.12, except meet the followi ng gradation as tested by ATM 304. TABLE 635 -1 SAND BLANKET MATERIA L GRADATION
635-3.01 CONSTRUCTIO N REQUIREMENTS. Prior to placing the insulation board, blade,
shape, and compact the area per Section 203. Place a sand blanket leveling course at least four inches thick. Finish the leveling course surface so it does not vary more than 0.10 foot when tested using a ten foot straightedge. Set each board accurately to the line and grade established and anchor firmly in place by driving a minimum of 2 wood dowels per panel. Place insulation to the required thickness, using a minimum of two layers. Stagger all joints between layers. Cover the insulation board with twelve inches of sand blanket material prior to placing subsequent lifts. Use approved spreading and compacting equipment.
635-4.01 METHOD OF M EASUREMENT . See Section 109.
Sand blanket material will be paid for under 203.0006._____ Borrow.
635-5.01 BASIS OF PA YMENT . Payment will b e made under:
PAY ITEM Item Number Item Description Unit 635.0001.____ Insulation Board MBM 635.0002.____ Insulation Board SF SIEVE PERCENT PASSING BY WEIGHT 2 in. 100 No. 4 15-65 No. 200 0-6 363 ALASKA 2020 SECTION 636 GABIONS
636-1.01 DESCRIPTION . Construct wire gabion bank protection at locations shown on the Plans.
636-2.01 MATERIALS. Use materials that conform to the following:
Gabions Subsection 712- 2.13 Gabion Backfill Subsection 703- 2.11
636-3.01 CONSTRUCTIO N REQUIREMENTS. Construct gabions to the lines and grades as
staked. Meet the details shown on the Plans. Assemble gabion baskets per the manufacturer's recommended procedures. Align each row or tier of gabion baskets before filling the baskets. Install tie wires in both directions horizontally so that layers between ties are not more than 14 inches thick. Space tie wir es not more than 14 inches apart horizontally within any gabion basket cell. Loop tie wires around at least 3 meshes of the gabion basket and tie or twist securely. Fill each gabion basket so the lid, when secure, will bear on the gabion filler. Securely f asten gabion baskets to all adjacent baskets, using sufficient wire to provide the same strength as the body of the mesh. Meet Section 204 for all excavation and backfill for gabions.
636-4.01 METHOD OF M EASUREMENT. By the calculated neat line volume of gabion baskets
in place using the manufacturer's specified dimensions.
636-5.01 BASIS OF PA YMENT. Excavation for gabions will be paid for under Section 204.
Payment will be made under: PAY ITEM Item Number Item Description Unit 636.0001.____ Gabion CY
Source: Alaska Standard Specifications for Highway Construction, 2020 Edition. Pages 390–390 of 584.