- 731 - SECTION 904 -- INERTIAL BARRIER MODULES
904.01 Description
1.The Contractor shall furnish and install sand filled inertial barrier modules (impact attenuators) at the locations shown in the contract.
904.02 Material Requirements
1.The inertial barrier modules shall be listed on the Department’s Approved Products List.
2.Filler material for inertial barrier modules shall meet the requirements for concrete fine aggr egate shown in Table 1033.02A. Salt shall be added to prevent freezing. The sand or filler material shall contain 5 to 15% (by volume) rock salt mixed with the filler material.
904.03 Construction Methods
1.The Contractor shall install the inertial barrier modules in accordance with the recommendations an d instructions of the manufacturer and as directed by the Engineer.
904.04 Method of Measurement
1.The inertial barrier modules shall be measured by the each.
2.Filler material shall be measured by the cubic yard (cubic meter).
904.05 Basis of Payment
1.P a y I t e m P a y U n i t Inertial Barrier Modules, Type _____ Each (ea) Filler Material for Inertial Barrier Modules Cubic Yard (CY) [ C u b i c M e t e r ( m 3)]
2.Payment is full compensation for all work described in this Section. - 732 - SECTION 905 -- ROCK RIPRAP
905.01 Description
1.The Contractor shall prepar e the slopes and furnish and place stone on the slopes at locations shown in the contract.
905.02 Material Requirements
1.a. The rock shall be sandstone , limestone, quartzite, or other hard stone. It shall be clean and free from earth, clay, or refuse.
b.The solid rock shall have a density of at least 140 lb/CF (2245 Kg/m3).
2.Each load of rock shall be graded as shown in Table 905.01. The rock shall be angular in shape to allow interlocking between the various rock sizes. Table 905.01 Rock Riprap Gradation Requirements Size of Rock Percent of Total Weight Smaller than the Given Size Type A 150 pounds (68 Kg) 35 pounds (16 Kg) 2 pounds (0.9 Kg) Not to exceed 10 Type B 300 pounds (136 Kg) 80 pounds (36 Kg) 5 pounds (2.2 Kg) Not to exceed 10 Type C 700 pounds (318 Kg) 150 pounds (68 Kg) 10 pounds (4.5 Kg) Not to exceed 10
3.a. Gradation control shall be done by a visual inspection that verifies the rock is reasonably well graded and does conform to the gradation requirements in Table 905.01.
b.Each piece shall have no dimension greater than 3 times its least dimension.
4.Rock riprap shall not have a soundness loss greater than 14% by weight at the completion of 16 cycles of freezing and thawing when tested in accordance with NDOT T 103. The rock riprap shall be prepared for the freezing and thawing tests by crushing to comply with the gradation requirements of coarse aggregate, as specified in Section 1033, Table 1033.03A, Class "E" aggregate.
905.03 Construction Methods
1.a. The finished earth surface shall conform to the grades and slopes of the neat lines of the bottom surface of the riprap as shown in the contract.
b.The Contractor shall excavate for energy dissipation holes (scour holes) as described in the contract.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 765–765 of 1,048.