513Concrete Pavement Cross Stitching

513.1-DESCRIPTION: Concrete pavement cross stitching consists of drilling holes and anchoring deformed reinforcing bars diagonally across longitudinal cracks. 513.2-MATERIALS: Materials shall meet the requirements of the following Subsections of Division 700: MATERIAL SUBSECTION Deformed Steel Reinforcing Bars 709.1 513.2.1-Material Requirements: Deformed Steel Reinforcing Bars shall be Grade 60. Anchoring Material and Dispensing Equipment - Use a pourable, two component, 100% solids structural epoxy which is approved by the Engineer. It shall be dispensed either from:

ii. Through a static nozzle that homogeneously mixes the material without any hand mixing first. 513.3-EQUIPMENT AND TOOLS: 513.3.1-Drills: Use a hydraulic drill with tungsten carbide bits. Control the forward and reverse travel of the drills by mechanically applied pressure. Mount the drill on a suitable piece of equipment such that it is quickly transported and positioned. Rest and reference the drill rig frame on and to the paveme nt surface such that the drilled holes are cylindrical and repeatable in terms of position and alignment on the surface being drilled. Hand -held drills are not permitted. 513.4-CONSTRUCTION METHODS: 513.4.1-Drilling Holes: Drill the end holes in a slab eighteen (18) – twenty (20) inches from the transverse joints. Drill interior slab holes at a maximum of twelve (12) inch spacing. Drill such that the:

ii. Hole centerlines are perpendicular to the crack at each location being drilled. iii. Adjacent holes are drilled in opposite directions across the crack. iv. Longitudinal centers of drilled holes are at the crack.

written recommendations. Those recommendations shall be submitted to the Engineer prior to the start of construction. vi. Hole bottoms are no more than one (1) inch from the slab bottom. Repair cracks that result from drilling with a full depth repair as approved by the Engineer. 513.4.2-Cleaning Holes: Clean the drilled holes in accordance with the anchoring material Manufacturer’s written recommendations. Those recommendations shall be submitted to the Engineer prior to the start of construction. As a minimum, clean holes with oil -free and moisture-free compressed air. The Engineer will check the compressed air stream purity with 286 a clean white cloth. The compressor must deliver air at a minimum pressure of 120 ft 3 per minute and develop a minimum nozzle pressure of 90 psi. Insert the nozzle the full depth of the hole, to the back of the hole, to force out all dust and debris. Also, clean any chipped areas at the surface resulting from drilling holes at an angle. Repair chipped area with the anchoring material. 513.4.3-Deformed Bar Installation: Unless otherwise specified by the Engineer, u se 0.75 inch diameter bars of sufficient length such that, when anchored, the top of the bar is 1.75 – 2 inches below the pavement surface and the center of the bar is at the crack. When using new cartridges of anchoring material, ensure the initial material exiting the nozzle appears uniformly mixed. If it is not uniformly mixed, waste the material until uniformly mixed material extrudes. Place the anchoring material in the back of the hole using a nozzle or wand of sufficient length. Insert the bar such that the anchoring material is evenly distributed around the bar and slightly extrudes out the hole as the bar is inserted. Trowel the anchoring material smooth to the pavement surface, filling any chipped areas. TABLE 513.4 Slab thickness (T), inches 8 9 10 11 12 Distance (X) from crack to centerline of hole, inches 6.9 7.8 8.7 9.5 10.4 Length of bar, inches 9 11 13 15 17 287 Typical Cross Stitching Repair Details 513.5-OPENING TO TRAFFIC: No traffic will be permitted on the cross-stitched pavement until the anchoring material can be expected, as shown by test data supplied by the anchoring material Manufacturer from an Independent Approved Laboratory, to have a compressive strength of at least 2,000 psi, unless otherwise approved by the Engineer. 513.6-METHOD OF MEASUREMENT: Concrete pavement cross stitching is measured by each deformed bar installed and accepted. 288 513.7-BASIS OF PAYMENT: The contract unit price paid for each deformed bar includes full compensation for furnishing and placing all the materials and the cost of all labor, tools, equipment, supplies, and incidentals necessary to complete the work in an acceptable manner. No payment will be made for items required by the Engineer to repair damage to the adjacent pavement incurred during drilling. 513.8-PAY ITEM: ITEM DESCRIPTION UNIT 513001-* Installation of Deformed Bar Each * Sequence number 289