275 SECTION 510 RE-SEALING CONCRETE PAVEMENT JOINTS
510.1 -DESCRIPTION : This work includes all labor, equipment, and material required to remove existing sealers, clean the joint, and seal the joint with a sealant meeting the requirements of section 510.2. The location of the joints to be sealed shall be as shown in the plans or as directed by the Engineer.
510.2 -MATERIALS : The joint sealant shall be in accordance with either section 7 08.3 or 708.4. The joint back -up material shall be in accordance with section 708.4.2, shall meet the requirements of the Sealant Manufacturer, and shall be appropriate for outdoor applications.
510.3 -CONSTRUCTION METHODS : 510.3.1 -Joint Preparation: All spalls along the joint which are directed by the Engineer to be repaired, shall be repaired as specified in section 506 for partial depth repair. The spalls shall be repaired prior to resealing the joint. Existing joint sealer or sealant shall be removed from the joint groove as designated by the Engineer. Where re -sealing in an area of previously installed sealant, a fresh sawcut shall be made to provide a clean face for the n ew sealant to bond. The new sawcut shall provide a joint groove of adequate width and depth to provide a width to depth ratio (shape factor), including joint back -up material, of 1:1 for hot -poured sealant and 2:1 for silicone sealant. Any damage done to newly placed sealant by re -sawing operations shall be repaired to the satisfaction of the Engineer. The longitudinal joints shall be sawed prior to resealing the intersecting transverse joints. Immediately following the final sawing operation, both ve rtical faces of the joint shall be completely free of dirt and dust; leaving a clean dry, newly exposed concrete surface. Joints shall be cleaned by sandblasting each vertical face with the nozzle held at an angle to the joint face and within one ( 1) or two (2) inches of the pavement. Sandblasting shall be done to a depth at which the sealant and backer rod are to be installed. Just prior to installing the back -up material, the joints shall be blown out with compressed air at a pressure of at least 90 psi to remove all dust, loose particles, and debris. Air compressors used for this purpose shall be equipped with traps capable of removing moisture and oil from the compressed air. A joint shall not be sealed until it is thoroughly clean and dry. After the final cleaning, the back -up material shall be inserted into the joint groove in accordance with the Manufacturer’s recommendations to provide the correct shape factor for the sealant being used.
510.3.2 -Joint Sealing: After insertion of the back -up material and prior to becoming contaminated, the joint groove shall be sealed in accordance with the Sealant Manufacturer’s recommendations. At the time of sealing, the joint groove faces shall be dry and dust free. The sealant shall be pumped into t he joint groove in a continuous uniform operation to properly fill and seal the joint groove from the bottom upward in order to avoid trapping any air bubbles. Tooling of the sealant, in order to force the sealant against the joint faces and provide a sli ghtly concave surface with a depth of approximately ¼ in ch (at the center of the joint) below the pavement surface, is required unless otherwise directed by the sealant manufacturer. When
276 not tooled, the joint groove shall be sealed flush to within 1/8 to 1/4 inch below the pavement surface. Traffic shall not be allowed on the sealed joint for the minimum time recommended by the Sealant Manufacturer after tooling or placement, unless otherwise approved by the Engineer. Sealant shall never be applied to frozen, dirty, wet, or damp concrete or during inclement weather conditions. Sealant shall not be placed in the joints unless the temperature of the pavement is 40°F or higher unless approved by the Engineer.
510.4 -METH OD OF MEASUREMENT : The quantity of r e-sealing concrete pavement joints to be paid for will be the number of linear foot complete in place and accepted.
510.5 -BASIS OF PAYMENT : Re-sealing concrete pavement joints will be paid for at the contract unit price per linear foot. Payment shall be full compensation for all labor, equipment, material, and incidentals required t o remove all existing sealers or sealants, clean the joint groove, install the back -up material, and seal the joint with sealant.
510.6 -PAY ITEMS: ITEM DESCRIPTION UNIT 510001 -* Re-Sealing Transverse Concrete Pavement Joints Linear Foot 510002 -* Re-Sealing Longitudinal Concrete Pavement Joints Linear Foot
* Sequence number
277 SECTION 511 DOWEL BAR RETROFIT
511.1 -DESCRIPTION : Dowel bar retrofit consists of installing epoxy -coated, round steel dowels into existing concrete pavement across transverse joints and/or cracks. Slots are cut using diamond -tipped saw blades, the existing concrete is removed, the dowels are placed in the slots across the joints or cracks, and the slots are backfilled.
511.2 -MATERIALS : Materials shall meet the requirements of the following Sections:
MATERIAL SECTION OR SUBSECTION Bond Breaker 511.2.1 or 707.9 Caulking Filler 511.2.1 Dowel Bar Support Chairs 511.2.1 Epoxy -Coated Dowel Bars 709.15 Expansion Caps 511.2.1 Foam Core Insert 511.2.1 Non-Shrink Concrete Backfill Material ASTM C928 and 511.2.1
511.2.1 -Material Requirements:
Bond Breaker: Acceptable bond -breaking compounds include white pigmented curing compound or other approved bond breaker materials. Apply bond breaker coating on all surfaces of the dowel bar, either at the manufacturing facility before shipment, or on -site. Do not apply bond breaker while the dowel bars are in place within the pavemen t section.
Dowel Bar End Caps (Expansion Caps): Use tight -fitting, commercial quality end caps made of a non -metallic, non -organic material that allow for ¼ inch of movement at each end of the dowel bar.
Dowel Bar Support Chairs: Use chair devices for supporting the dowel bars that conform to the epoxy -coated steel requirements of ASTM A884, or are fabricated from commercial quality, nonmetallic, non -organic material. Dowel bar chairs are used to firmly hold the dowels centered in the slots during b ackfill operations. Design the dowel bar chairs to hold the bar a minimum of ½ inch above the bottom of the slot while the backfill material is placed and consolidated.
Foam Core Insert: Use a foam core insert to re -establish the joint or crack. The insert shall consist of rigid styrofoam material or closed cell foam, faced with poster board or plastic material. The foam core insert (joint/crack re -former) allows each side of the slot to expand and contract. Ensure that the insert extends up to the bottom of the existing joint sealant reservoir.