Division 500 — Section 505
500-42 Section 505 — Repairing Random Cracks in PCC P
505.1 Description 1 Route, clean, and seal cracks with silicone sealant in existing Portland cement concrete pavement . These cracks are random cracks other than the standard crack patterns in continuously reinforced concrete pavement or transverse cracks in jointed concrete pavement. In general, these cracks are usually opened ⅛ in. or more and are greater than 10 ft in length. The RCE will identify and mark cracks to be rehabilitated. 505.2 Materials 1 Use hot -pour sealant and associated materials meeting the requirements of Section 501. 505.3 Construction 505.3.1 General 1 Prepare cracks by removing any existing sealant, re -facing and cleaning the crack, installing blocking medium as needed, and sealing the crack. 505.3.2 Equipment 1 Use sealing equipment according to Subsection 501.3 .1. Use a concrete saw with a pivotal small diameter blade that follows the crack to provide a reservoir for the sealant material. 505.3.3 Preparation of Cracks 1 Remove old sealant, re- face, and clean cracks according to Subsection 504.3.2 . Widen the cracks to the widths and depths shown in the Plans or as directed by the RCE . 2 For cracks ⅜ in. or greater in width, install a backer rod in the crack at a uniform depth to prevent entrance of the sealant below the depth specified. Use backer rods that are compatible with the sealant, and install using the sealant manufacturer's recommendation. Do not stretch the rods during installation. 3 For cracks less than ⅜ in. wide, the use of a blocking medium is optional if the seals produced are satisfactory. If the seals prove to be unsatisfactory, the RCE may require subsequent crack rehabilitation to include installation of a blocking medium.