- 754 - SECTION 916 -- CATCH BASINS, MANHOLES, INLETS, AND JUNCTION BOXES
916.01 Description
1.The Contractor shall construct catch basins, manholes, inlets, junction boxes, and similar concrete struct ures as described in the contract.
916.02 Material Requirements
1.All materials shall conform to the requirements in Table 916.01. Table 916.01 Material Requirements Applicable Materials Section Concrete Risers and Tops ...................... 1037 Portland Cement Concrete ..................... 1002 Reinforcing St eel .................................... 1020, 1022, 1023 Structural Steel ....................................... 1045 Steel Casti ngs ........................................ 1050 Gray Iron Castings ................................. 1051 Paints and Paint Material s ...................... 1077
2.Concrete shall be Class 47B-3,000 (47B-20).
916.03 Construction Methods
1.The Contractor shall excavate to the dimensions shown in the contract.
2.The Contractor shall backfil l as described in Section 702 for culverts.
3.Reinforcing steel shall be handled and placed in accordance with the requirements of Section 707.
4.Concrete construction shall be performed in accordance with the requirements of Section 704.
5.The foundation excavation sha ll be dewatered and stable before concrete is placed.
6.a. When footings can be placed on the dry excavation without the use of cribs or cofferdams, back forms may be omitted when the soil will provide a smooth, plumb surface.
b.Concrete placed outside the dimensions shown in the contract will be at no additional cost to the Department.
7.a. Structural steel and miscell aneous metals shall be fabricated and placed as provided in Section 708.
b.Castings shall be made in conformance with AWS Standard Specifications.
c.All castings shall be set on full mortar beds or otherwise secured as shown in the contract. They shall be set accurately to the correct elevation so that subsequent adjustments will not be necessary.
8.Structural steel shall be painted in accordance with the requirements of Section 709. Catch Basins, Manholes, Inle ts, and Junction Boxes 916.05 - 755 - 916.04 -- Method of Measurement
1.Manholes are measured by the each.
2.Concrete for catch basins, inlets, and junction boxes is measured as described in Section 704.
3.Reinforcement for catch basins, inlets, and junction boxes is measured as described in Section 707.
4.Structural steel and miscella neous metals are measured by the pound (kilogram) and are included in t he pay item "Structural Steel".
5.a. "Cast Iron _____" and "Castings" are measured by the pound (kilogram).
b.The weight of castings shall be computed by the Department from dimensions shown in the contract with an addition of 3% for fillets and overruns.
916.05 Basis of Payment
1.P a y I t e m P a y U n i t Manhole ___________ Each (ea) Concrete for _________ Cubic Yard (CY) [ C u b i c M e t e r ( m3)] Reinforcing Steel for _______ Pound (lb) [ K i l o g r a m ( K g ) ] Epoxy Coated Reinforcing Steel ______ Pound (lb) [ K i l o g r a m ( K g ) ] Structural Steel _____ Pound (lb) [ K i l o g r a m ( K g ) ] Cast Iron ______ Pound (lb) [ K i l o g r a m ( K g ) ] C a s t i n g s P o u n d ( l b ) [ K i l o g r a m ( K g ) ]
2.Excavation for catch basins, manholes, inlets, and junction boxes is subsidiary to the appropriate structure.
3.Concrete and reinforcing steel are subsidiary to "Manhole _____". 4. Concrete, except that used in the construction of manholes, shall be paid for in accordance with the provisions of Section 704.
5.Reinforcement, except that us ed in the construction of manholes, shall be paid for in accordance with the provisions of Section 707.
6.The depth of any manhole, ex cept a precast manhole, may be increased or decreased from the depth i ndicated in the contract by not more than 1 foot (300 mm) without any adjust ment in compensation. When the depth of a manhole is increased or decreased more than 1 foot (300 mm), the change in quantities and the adjust ment in prices, when necessary to reflect the change in design, shall be recorded in a supplemental agreement.
7.Payment is full compensation for all work described in this Section. - 756 - SECTION 917 -- RECONSTRUCTION OF MANHOLES AND ADJUSTING MANHOLES TO GRADE
917.01 Description
1.The Contractor shall adjust th e manhole elevations or reconstruct the manhole as described in the contract.
2.Adjusting a manhole elevation is defined as lowering the top 6 inches (150 mm) or less or raising t he top not more than 1 foot (300 mm).
3.Reconstructing a manhole is defined as lowering the top more than 6 inches (150 mm) or raising the top by more than 1 foot (300 mm).
917.02 Material Requirements
Brick mortar shall be 1 part cement, 2 parts sand, and water as necessary to insure brick can be set at designed spacing.
917.03 Construction Methods
1.The Contractor shall:
a.Remove and replace the necessary surfacing to allow adjustment of the manhole.
b.Remove the castings and adj ust the tops of the manholes by removing or adding concrete or brick, as the case may be.
c.Reset the frames and covers. 2. The work of reconstructing m anholes or adjusting manholes to grade shall be performed in accordance with the requirements of Subsection
916.03 when concrete is used.
3.Bricks shall be approved by the Engineer. The bricks shall be bonded in mortar. All brick must be wetted before being placed. All joints shall be completely filled with mortar and shall be 3/8 inch (9 mm) thick.
4.The Contractor shall provide and set all cast iron covers, rings, frames, flanges, and other items as described in the contract.
917.04 Method of Measurement
1.Adjusting manholes to grade will be measured by the each. 2. Reconstructing manholes will be measured by the each.
3.Cast iron is measured by the pound (kilogram).
917.05 Basis of Payment
1.P a y I t e m P a y U n i t Reconstruct Manhole Each (ea) Adjust Manhole to Grade Each (ea) Reconstruct Manhole _____ Each (ea) Cast Iron _____ Pound (lb) [ K i l o g r a m ( K g ) ]
2.Payment is full compensation for all work described in this Section.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 788–789 of 1,048.