Attachment_10_SECTION_811-_Blading.pdf

811 BLADING (2/99)

1. DESCRIPTION

This work consists of surface blading native or aggregate roads to a condition to facilitate traffic and provide proper drainage. Blading includes shaping the crown or slope of traveled way, maintaining berms and drainage dips, and compacting the surface in accordance with this specification.

2. MAINTENANCE REQUIREMENTS

a. Timing

Surface blading shall be performed during the contract period as ordered by the Government.

b. General

1. The existing traveled way and shoulders, including turnouts unless otherwise ordered, shall be bladed and shaped to produce a surface which is uniform, consistent to grade, and crowned or cross-sloped as indicated by the character of the existing surface unless otherwise Marked on the Ground, to at least one half inch (1/2") per foot of width, but not more than three quarter inch (3/4") per foot of width. Surfacing materials shall be thoroughly loosened to a depth of no less than 2 inches or the depth of potholes or corrugations. Corrugations are washboarding and similar defects.

Scarification to facilitate cutting to the full depth of potholes or corrugations may be elected by the Contractor but will be considered incidental to blading. Scarification shall not go deep enough to cause contamination of the surfacing.

2. When Section 891 is included in the Road Listing, the Contractor shall apply water during blading when sufficient moisture is not present to prevent segregation.

Water supply, hauling, and application shall be in accordance with Section 891 and shall be incidental to blading unless Pay Items for Section 891 are included in the Schedule of Items.

3. Existing native, rock or aggregate surfaced drainage dips shall be cleaned and shaped incidental to blading to divert surface runoff to existing outlet devices, ditches and discharge locations.

4. The Contractor shall establish a blading pattern which provides a uniform driving surface, retains the surfacing on the roadbed and provides a thorough mixing of the materials within the completed surface width. Upon final blading, no disturbed rock shall protrude more than two (2) inches above the adjacent surface unless otherwise provided in the contract. Material not meeting this dimension shall be removed and placed outside the roadbed so as not to obstruct drainage ways or structures. This material may be scattered off the roadbed if there is free drainage.

c. Routine Blading

1. Excess roadbed width shall be shaped only as needed to provide drainage away from the traveled way. Established grasses and other vegetation shall not be removed from the excess width except as incidental to providing drainage or unless otherwise provided in the contract.

d. Compaction

All roads bladed under this section shall be compacted using Method A. Compaction Method A is considered incidental to blading.

Compaction shall commence immediately following blading. Compaction methods are:

Compaction Method A: By breaking track while operating equipment on the bladed surface. Compaction shall cover the full width bladed surface.

Compaction Method B: 8-10 ton pneumatic, steel or equivalent vibrating roller, operated to cover the full width of the bladed surface two (2) times.

e. Intrusions

Where the minimum width of 12 feet is not available, the Contractor shall construct berms where ordered and marked on the ground. Material to provide berms will come from sources designated by the Government.

f. Undercutting

Roadway backslope shall not be undercut.

g. Intersections

1. Intersections with side roads which are not closed or restricted to vehicular use shall be bladed to assure smooth transitions.

2. Field evidence of closure or restrictions shall be considered to be signing, cross ditching in the road surface (traveled way), earth berms or other devices placed to discourage or eliminate use by passenger cars. Also, roads listed for work under Sections 835 or 838 shall be considered restricted.

3. Side roads listed for work under this Section shall be considered as not restricted.

h. Cleaning of Structures

Materials resulting from work under this Section shall not be allowed to remain on or in structures, such as bridges, culverts, cattleguards, drainage dips, aprons, or flumes.

i. Berms

Existing berms shall be maintained to the condition of adjacent segments when ordered by the Government.

j. Scarification

1. This work shall consist of destroying or breaking up old or damaged chip seal and dust oil surfaces and the loosening of native and pit run surfaces for blading and reshaping the road surface.

2. Scarification shall be accomplished by rippers spaced not more than 12 inches apart.

3. Scarification shall not penetrate the aggregate base to the subgrade. Where aggregate base is 3 inches or greater in depth, the minimum scaification depth shall be 3 inches.

3. MEASUREMENT

Measurement under this Section will be made by the total number of units for each item listed in the Schedule of Items completed and accepted.

a. Measurement for blading will be single-lane mile measured along the centerline of the roadway (see quantity measurement terms). Two-lane roads will be measured as two (2) single-lane miles. Measurement will be to the nearest one-tenth (0.1) mile.

b. Each intersection bladed under 2.g. will be equivalent to one-tenth (0.1) single-lane mile; however, when the intersecting side road is scheduled for subsequent blading under this Section, no measurement will be made.

c. Berm maintained or established will be measured by linear foot.

d. No measurement will be made under this Section for Compaction Method A.

Measurement for Compaction Method B will be the same as stated in 3.a for blading.

4. PAYMENT

a. The quantities measured and accepted will be paid for at the contract unit price shown in the Schedule of Items.

b. Payment will be made under:

Pay Item Pay Unit

811(1) Blading Surfaced Roads Mile 811(2) Blading Native and Pit Run Roads Mile 811(3) Berm Maintained Mile 811(4) Establishing Berms Mile 811(5) Compaction - Method B Mile 811(6) Scarification Pass Mile