609REINFORCED CONCRETE BRIDGE APPROACHES

609.01Description

This work shall consist of constructing reinforced concrete bridge approaches, RCBA, and extensions require d for bridge railing transitions in accordance with

105.03

MATERIALS

609.02Materials 10

Materials shall be in acco rdance with the following:

Coarse Aggregate, Class B or Higher, Size No. 8 ....... 904.03 Coarse Aggregate, Class D or Higher, Size No. 53 ..... 904.03 Curing Materials .......................................................... 912.01 Geotextile for Pavement and Subgrade ....................... 918.02 Joint Materials ............................................................. 906.02(a)1 Reinforcing Bars, Epoxy Coated ................................. 910.01 Support Devices .......................................................... 910.01(b)11 20 Threaded Tie Bar Assembly ........................................ 910.01(b)2

CONSTRUCTION REQUIREMENTS

609.03General Requirements

Subgrade shall be prepared in accordance with 207. Subbase shall be prepared in accordance with 302. Geotextile shall be installed in accordance with 214.

The RCBA extension shall be placed only where a concrete bridge-railing transition shall be located on the RCBA. If the transition shall be placed on the bridge, 30 the RCBA shall be placed as shown on the plans.

609.04Forms

Forms shall be either steel or wood and shall be in accordance with 508.04(c)1 or

508.04(c)2

609.05Joints

Longitudinal construction joints will only be allowed as shown on the plans. The Type I-A joint shall be constructed as shown on the plans.

Type I-A joints shall be created by sawing slots using sawing equipment in accordance with 508.07. The joint shall be cut in two operations. The initial saw cut shall commence as soon as the concrete has hardened sufficiently to enable sawing without raveling, usually 2 to 12 h after placement.

The second saw cut shall be made after the concrete has sufficiently cured, but 609.01

before opening the RCBA to all traffic. Slurry or saw residue remaining in the slot shall be immediately flushed. Construction traffic shall not be on the RCBA after the second saw cut until the joint is sealed.

The sawed slot shall be cleaned to remove all foreign matter from the entire depth of cut. Joint sealing shall be in accordance with 503.05.

609.06Reinforcing Bars

Furnishing and placement of reinforcing bars shall be in accordance with 703.

609.07Thickness

The depth of the RCBA will be checked by the Engineer prior to pouring, by making stringline measurements every 3 ft across the width of the approach. Any location deficient in depth by 1/2 in. or more shall be corrected prior to placing the 60 concrete.

609.08Concrete Placement

The subbase shall be uniformly moist at the time of concrete placement. Delivery and placement of concrete shall be in accordance with 702.

609.09Finishing

The RCBA shall be finished with equipment in accordance with 508.04(c)3 and

(c)4. The operations shall be controlled so that an excess of mortar and water is

not worked to the top. Long-handled floats may be used to smooth and fill in open 70 textured areas. The edges of formed RCBA shall be tooled or chamfered.

The finished RCBA surface shall be textured with a double thickness burlap drag or a minimum 4 ft wide turf drag. Longitudinal grooving shall be in accordance with

722.11and shall not commence until the smoothness has been measured in accordance

with 609.11.

609.10Curing

RCBA shall be wet cured in accordance with 702 or shall have liquid membrane forming curing compound applied and maintained in accordance with 504.04(a) to 80 exposed surfaces within 30 minutes after the finishing operations have been completed. The edges of the RCBA shall be cured immediately upon removal of the forms. The edge shall be covered with curing materials equal to the material used on the surface or banked with soil 12 in. wide or greater.

When conditions arise whic h prevent timely application of curing materials the surfaces shall be kept wet with a fine spray of water. The fine spray of water shall continue until application of curing materials is resumed.

609.11Smoothness 90

The smoothness of the surface of the RCBA will be measured by means of a 10 ft straightedge as soon as practical following curing or completion of adjoining 609.11

roadway or structure sections. All surface vari ations shall be corrected to 1/8 in. or less.

Smoothness variations outside specified tolerances shall be corrected in accordance with 502.20.

609.12Opening to Traffic

The RCBA may be opened to equipment and traffic when the flexural strength of 100 the test beams indicates the concrete has attained a modulus of rupture of 550 psi or greater.

The Contractor and Engineer will conduct an inspection of the new RCBA for any damage. The inspection and all necessary re pairs shall be completed prior to opening to traffic.

609.13Method of Measurement

Reinforced concrete bridge approaches, including extensions required for bridge railing transitions, will be m easured by the square yard. Subbase for PCCP will be 110 measured in accordance with 302.08. Subg rade treatment will be measured in accordance with 207.05. Geotextile will be measured in accordance with 214.05. Reinforcing bars will be measured in accordance with 703.07. Threaded tie bar assemblies will be measured in accordance with 703.07.

Longitudinal grooving will be meas ured in accordance with 722.15.

Finishing and curing of the RCBA will not be measured for payment. Construction joints or Type I-A joints will not be measured.

609.14Basis of Payment

Reinforced concrete bridge approaches, including extensions required for bridge railing transitions, will be paid for at the contract unit price per square yard. Subbase for PCCP will be paid for in accordance with 302.09. Subgrade treatment will be measured in accordance with 207.06. Geotex tile will be paid for in accordance with

214.06. Reinforcing bars will be paid for in accordance with 703.08. Threaded tie bar

assemblies will be paid for in accordance with 703.08.

Longitudinal grooving will be paid for in accordance with 722.16.

Payment will be made under:

Pay Item Pay Unit Symbol

Reinforced Concrete Bridge Approach, ________ in. .............. SYS thickness

The cost of finishing, furnishing and placing curing materials shall be included in the cost of the RCBA. 609.12

The cost of corrections for smoothness or re-texturing shall be included in the cost of the RCBA.

The cost of all labor and materials for the placement of construction joints and Type I-A joints shall be included in the cost of the RCBA.