for Highway Construction Page 486 of 715 SECTION 608 – PIPE APRONS
608.01 Description.
Provide and ins tall aprons as specified to the inlet and outlet ends of pipe culverts.
608.02 Materials.
Provide material aprons as specified in: Concrete Aprons ........................................................................................................................... 509 Metal Aprons ........................................................................................................................... 708.21 Use galvanized or stainless steel bolts , nuts, and washers. Galvanize other material to meet AASHTO M 232. Fabricate safety, longitudinal, and opt ional bars from steel pipe meeting the requirements of ASTM A53 Schedule 40 and hot -dipped galvanize the bars after fabrication for metal safety aprons . Use galvanized steel that meets AASHTO M 111. Use Class 30 concrete for apron cutoffs. Use conc rete aprons that meet the reinforced Class III concrete pipe. Provide metal or concrete aprons for installation. Attached aprons are required to use the same m aterial as the aprons used for the pipe material.
608.03 Construction Requirements.
Shape area occupied by the apron to conform to the bottom of the structure and to provide a firm and uniform support over its entire area. Backfill cutoff walls and areas adjacent to the apron to prevent undercutting or erosion.
608.04 Method of Measurement.
The Engineer will measure acceptably completed work by the each. The Engineer will include the culvert sections attached to aprons in the measurement of the culverts.
608.05 Basis of Payment .
The Department will pay for accepted quantities at the contract unit prices as follows: Pay Item Pay Unit ___ Aprons for Pipe ................................................................................ Each ___ Metal Safety Apron (Parallel) ........................................................... Each ___ Metal Safety Apron (Cross Drainage) .............................................. Each Structure excavation and compacting backfill are incidental and the cost included in the pipe apron unit price. Concrete for the cutoff is incidental and is included in the aprons contract unit price. for Highway Construction Page 487 of 71 5 SECTION 609 – MINOR STRUCTURES
609.01 Description.
Construct minor structures (e.g., drops, weirs, checks, diversion boxes, culvert and siphon headwalls, and inlet and outlet structures for canals and pipes).
609.02 Materials.
Provide materials as specified in: Concrete ....................................................................................................................................... 509 Reinforcing Steel ..................................................................................................................... 708.02 Timber .......................................................................................................................................... 710 Use Class 30 concrete. The Engineer will reject bars with failing heat numbers. The Engineer will reject reinforci ng steel delivered that cannot be identified by heat number Replace rejected reinforcing steel at no cost to the Department. Provide metal grates that meet the requirements of ASTM A36. Meet the requirements of the American Weldi ng Society D1.1 when welding the grates. Use grates for the inlet headwalls only when specified. Grates do not need to be painted or galv anized.
609.03 Construction Requirements.
Excavate and backfill as specified in 210. Construct minor structures as specified in 503 and 509.
609.04 Method of Measurement.
The Engineer will measure acceptably completed work as follows:
1.Concrete by the cubic yard as specified in 509.
2.Metal reinforcement by the pound of reinforcing steel as specified in 503.
3.Timber and lumber by the thousand feet board measure (MFBM).
4.When minor structures are by each, material is incidental .
609.05 Basis of Payment .
The Department will pay for acceptable quantities at the contract unit prices as follows: Pay Item Pay Unit Concrete ................................................................................................. CY Metal Reinforcement .............................................................................. lb Timber, Treated ...................................................................................... MFBM Timber, Untreated ................................................................................... MFBM Minor Structures ..................................................................................... Each
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 522–522 of 768.