KANSAS DEPARTMENT OF TRANSPORTATION SPECIAL PROVISION TO THE STANDARD SPECIFICATIONS, 1990 EDITION

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1 Sheet 1 of 5 KANSAS DEPARTMENT OF TRANSPORTATION SPECIAL PROVISION TO THE STANDARD SPECIFICATIONS, 1990 EDITION NOTE: This special provision is generally written in the imperative mood. The subject, "the Contractor" is implied. Also implied in this language are "shall", "shall be", or similar words and phrases. The word "will" generally pertains to decisions or actions of the Kansas Department of Transportation. DIVISION PRECAST REINFORCED CONCRETE BOX 1.0 DESCRIPTION. Unless shown otherwise on the Plans, the Engineer will allow precast reinforced concrete boxes in place of cast-in-place RCBs. When shown on the Plans, or when provided as an option to cast-in-place RCBs, furnish the precast reinforced concrete box sections in the sizes shown on the Plans. Furnish the required materials and install the precast reinforced concrete box sections at the locations shown on the Plans. BID ITEM Reinforced Concrete Box ( * ) (Precast) * size UNIT meter 2.0 MATERIALS. (a) Precast Reinforced Concrete Box. Provide precast reinforced concrete box sections that comply with the requirements of ASTM C 1433M, Table 2. Exceptions and additions to the above requirements are as follows: ASTM Section 11. PERMISSIBLE VARIATIONS. Revise the first sentence of subsection 11.1 to read: The internal dimensions shall not vary more than one percent (or 20 mm, whichever is less) from the design dimensions. ASTM Section 11. PERMISSIBLE VARIATIONS. Add the following subsections: 11.8 Deviation from straightness of mating edge: +5 mm Squareness of ends (vertical and horizontal): +5 mm With any new production start-up, or change in set-up, join a minimum of the first five production units at the fabrication plant for inspection of joint fit-up and alignment of boxes. Continue joining each unit until production is satisfactory. After that, check approximately ten percent of the remaining production

2 Sheet 2 of 5 at random, using a minimum three unit assembly. The inspector may order a three or more unit assembly at any time his measurements or observations indicate a problem exists. Multiple-cell precast reinforced concrete boxes shall be designed according to the criteria used to develop the single-cell precast boxes. The minimum member thickness shall be not less than three-fourths the thickness of the corresponding member of an equivalent KDOT Standard cast-in-place rigid frame box culvert, but not less than 150 mm. When calculating the minimum thickness of the bottom slab, deduct 10 mm from the cast-in-place thickness before factoring by three-fourths. Clearances to reinforcing shall be a minimum of 30 mm +5 mm from all faces except when the depth of fill is less than 600 mm, in which case the clearance in the top of the top slab shall be 65 mm +5 mm. Epoxy coated reinforcing shall be used in the top slab when the fill at the shoulder line is 150 mm or less. Fill heights less than 600 mm require a distribution slab. Precast distribution slabs may be used for fill heights over 300 mm, otherwise use cast-in-place. One of the following combinations of steel reinforcement may be used: a) one or two layers of mesh, or b) one layer of mesh and one layer of reinforcement bars, or c) one layer of reinforcement bars. The reinforcement shall be developed in accordance with applicable parts of Section 8, Division I of the AASHTO Standard Specifications for Highway Bridges. Longitudinal reinforcing for shrinkage and temperature requirements shall be a minimum of 125 mm 2 /m in each face, except at joint (see "Open Joint Detail" on the Plans). The transverse steel areas in each face shall be a minimum of 400 mm 2 /m of barrel. The maximum shear reinforcement spacing in the longitudinal direction shall be 150 mm. Welding will not be allowed on reinforcing bars or steel fabric, except that the original welding required to manufacture wire fabric is acceptable. Air entrainment is not required for dry-cast units. Use air entrainment for wet-cast units where the depth of fill will be less than 600 mm, as shown on the plans. Material for precast reinforced concrete boxes shall conform to the following requirements of the Standard Specifications: Class AAA (AE) Concrete Section 400 Reinforcing Steel (Grade 420) Section 1600 Reinforcing Steel (Epoxy Coated) (Grade 420) Section 1600 Concrete Admixtures Section 1400 Minimum length of a precast section shall be 1.2 m. A single-cell box of equivalent area may be substituted for a double-cell box with cell spans less than or equal to 1.8 m. Any revision in the cell height from that shown on the Plans will not be permitted unless approved by the Engineer. Two single-cell boxes may be substituted for a double-cell box, if approved by the Engineer. Prior to fabrication, the Contractor shall furnish shop drawings to the Engineer for review. Shop drawings shall detail all phases of construction including layout, joint details, lifting

3 Sheet 3 of 5 devices, casting methods, construction placement and details of any cast-in-place sections. Proposed transportation methods shall be noted on the shop drawings. Copies of overheight and overload permits, when required, shall be submitted with the shop drawings. The following information shall be legibly marked on an inside face of each box section by waterproof paint or other approved means: * Date of manufacture. * Name or trademark, and location of the manufacturer. * Mass of box section in metric tons. * The top of the box. Allow the Engineer or his representative free access to the manufacturing plant at all times for the purpose of inspecting materials, plant facilities and manufacturing and curing procedures. Inform the Engineer of planned concrete placement and curing schedule before work is started. Precast reinforced concrete boxes will be accepted on the basis of satisfactory results of material tests performed by the Engineer, compliance with dimensional requirements, and visual inspection at the point of usage. (b) Materials for Cast-In-Place Concrete Work. Furnish materials for cast-in-place concrete work conforming to the following requirements of the Standard Specifications: Class AAA Concrete Section 400 Reinforcing Steel (Grade 420) Section 1600 Reinforcing Steel (Epoxy Coated) (Grade 420) Section 1600 (c) Materials for Sealing Joints of Precast Boxes. Furnish a compound type joint filler or rubber gasket conforming to the following requirements of the Standard Specifications: Materials for Filling and Sealing Joints in Pipe Section 1500 Furnish an external sealing band conforming to the following requirements: External Sealing Band ASTM C877M The basis of acceptance for external sealing bands will be a Type D Certification as specified in Section 2600 of the Standard Specifications. Furnish geotextile fabric conforming to the following requirements: Fibers used in the manufacture of geotextile filter fabric shall consist of long chain synthetic polymers, polyesters, or olyamides. They shall be formed into a network such that the filaments or yarns retain dimensional stability relative to each other, including selvedges. These materials shall conform to the physical requirements shown below.

4 Sheet 4 of 5 Apparent Opening Size ASTM D 4751 U.S. Standard Sieve 300 µm Permittivity ASTM D per sec. minimum Grab Strength ASTM D N minimum, either pr direction Seam Strength ASTM D N minimum Ultraviolet Degradation at 150 hrs ASTM D % retained Furnish geotextile rolls with suitable wrapping for protection against moisture and extended ultraviolet exposure prior to placement. Label or tag each roll to provide product identification sufficient for inventory and quality control purposes. Store rolls in a manner which protects them from the elements. If stored outdoors, elevate and protect with a waterproof cover. The geotextile will be accepted on the basis of a Type A Certification as specified in Section 2600 of the Standard Specifications. The materials will be certified to meet the minimum average roll values as shown above. (d) Foundation Materials for Precast Boxes. Furnish either crushed stone or concrete seal course for the foundation of the precast box. Crushed stone shall be free of soapstone, shale, shalelike, or other easily disintegrated material. The gradation of the crushed stone shall be adequate to provide a uniform foundation. The Project Engineer will accept the crushed stone on the basis of visual inspection at the point of usage. Concrete for seal course shall be commercial grade concrete conforming to the requirements of the Standard Specifications, or any other concrete used on the project. 3.0 CONSTRUCTION REQUIREMENTS. (a) Foundation Preparation. Excavate and prepare the foundation according to the Standard Specifications. Provide a 150 mm (minimum) thickness of crushed stone, or 75 mm of concrete seal course for the foundation of the precast box. (b) Installation of Precast Box Sections. Lay the precast reinforced concrete box culvert with the groove end of each section up-grade. Join the sections tightly. Seal the joints using one of the options shown on the Plans. Install the joint sealant according to the manufacturer's recommendations. When geotextile is used to wrap the joint, the following requirements govern: Use only geotextile that has been properly stored. Limit the exposure to the elements (between placement and covering) of the geotextile to a maximum of seven calendar days. Avoid dropping any backfill larger than 150 mm D 50 size onto the geotextile from a height greater than 300 mm. Avoid dropping any backfill smaller than 150 mm D 50 size onto the geotextile from a height greater than one meter. Avoid contaminating the geotextile with grease, mud, or other foreign substances. Replace contaminated or damaged geotextile. When approved by the Engineer, repair damaged geotextile by placing a patch over the damaged area and sewing the patch to the geotextile. The patch shall extend a minimum of 300 mm beyond the perimeter of the damaged area. Replacement of contaminated or damaged geotextile, or repair if approved, is at the Contractor's expense.

5 Sheet 5 of 5 Fill the lifting holes with precast plugs sealed with mastic or mortar. (c) Cast-In-Place Requirements. Unless otherwise approved by the Engineer, construct cast-in-place collars at horizontal and vertical changes in RCB alignment. Construct cast-in-place end sections and wingwalls, except as noted on the Plans. When required by the Engineer, construct cast-in-place sections at the junctions of drainage structures. Construct the cast-in-place sections according to the Standard Specifications and as detailed on the Plans. 4.0 MEASUREMENT AND PAYMENT. When shown on the Plans, precast reinforced concrete boxes will be measured by the meter. The accepted quantity for which payment is made will be the quantity shown in the Contract, unless otherwise revised in writing by the Engineer. Precast end sections, and cast-in-place end sections and wingwalls will not be measured for payment, but will be subsidiary to the precast reinforced concrete box. Payment for "Reinforced Concrete Box ( * ) (Precast)" at the Contract unit price will be full compensation for the specified work. When provided as an option to cast-in-place RCBs, the precast reinforced concrete boxes will not be measured, but instead, the cast-in-place quantities will be the basis of payment. Payment of the cast-in-place quantities at the Contract unit prices will be full compensation for the specified work BD(BS)/M&R Precast RCB Sections m 90M-190-R* ACCP