253 sawing operations shall be cleaned by wire brushing, sandblasting, or a high pressure water blast or by a combination of these methods. Just prior t o 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 mo isture and oil from the compressed air. A joint shall not be sealed until it is thoroughly clean and dry. When recommended by the manufacturer, the vertical surfaces of joints shall be fully wetted by a primer. The primer and application, including all safety precautions, shall be as per the manufacturer's recommendations. The primer shall be allowed to dry tack -free prior to installation of the backer rod. The back -up material shall be installed in the joint at the required depth. The silicone sealant shall then be applied from inside the joint in a manner which causes it to wet the joint faces and to reasonable close conformity with the required dimensions. Immediately following placement of the sealant and before a skin forms, the sealant shall be tooled to force it against the joint faces and to provide a slightly concave surface with a depth of approximately ¼ inch (at the center of the joint) below the pavement surface. Any unreasonable deviation from the required joint or sealant dimensions will be just cause for rejection of the joint until satisfactory corrective measures are taken by the Contractor at no additional cost to the Division . Any failure of the joint material in either adhesion or cohesion will be cause for rejection of the joint, and the joint shall be repaired to the Engineer's satisfaction by the Contractor at no additional cost to the Division. Silicone sealant shall never be applied to frozen, dirty, wet, or damp concrete or during inclement weather conditions. Silico ne sealant shall not be placed in the joints without the approval of the Engineer when the temperature at the surface of the concrete is less than 40 F.
501.16.2 Performed Elastomeric Seal: The dimensional requirements shall be as
specified on the Plan s. Joints shall be clean and dry at the time the elastomeric seal is installed. Just prior to installation of the seal, the lubricant -adhesive shall be applied to the joint faces or the sides of the seal, or both, to facilitate installation of the seal a nd to help secure the seal in place in the joint. The lubricant -adhesive shall be applied in such a manner as to cover both sides of the seal over the full area in contact with the joint faces. Any lubricant -adhesive that gets on top of the seal shall be immediately removed. Seals shall be installed in a substantially full compressed condition with the vertical axis of the seal parallel to the joint faces. Seals shall be installed in the joints to the depth shown on the Plans using suitable machines or tools that will not twist, curl, nick, notch, or otherwise damage the seal and that will insert the seal in such a manner that elongation of the seal shall not exceed five percent (5%) . The in place seals shall be one -piece construction, without field or factory splices, for the full length of the joint. Any seal that is damaged during installation shall be removed and replaced with a new, undamaged seal. Any seal that is improperly installed or po sitioned in the joint or that shows more than five percent (5%) elongated following installation shall be removed and properly reinstalled or replaced.
501.17 Protection of Pavement :
The Contractor shall protect the pavement and its appurtenances against both public traffic and the traffic caused by their own employees and agents. This protection shall include watchmen to direct traffic, and the erection and maintenance of warning si gns, lights, barricades, pavement 254 bridges, crossovers, etc. The above shall be arranged so as not to interfere with public traffic on any lane intended to be kept open. All damage to the pavement occurring prior to final acceptance shall be repaired or t he pavement replaced, as the Engineer may direct.
501.18 Opening Pavement To Traffic :
If approved by the Engineer, the Contractor may open the pavement to traffic prior to twenty -eight ( 28) days after placement of concrete, provided tests conducted in accordance with subsection 501.4.4 indicate the pavement has attained the 28 -day design st rength. If the Contractor wishes to open pavement to traffic prior to age 28 days, then all provisions for making test specimens and conducting and reporting the tests shall be handled by the Contractor at their expense. However, the Engineer may require that the pavement not be opened to traffic for a period of 28 days or longer, after placement of concrete, if conditions make it advisable to extend this time.
501.19 Tolerance In Pavement Thickness :
It is the intent of these Specifications that the pavement shall be constructed in substantial conformity with the specified thickness. Paving operations shall be directed toward obtaining an average and uniform thickness equal to or greater than the specified thickness. For the purpose of establishing an adjusted unit price for pavement areas deficient in thickness, the thickness characteristics will be determined in accordance with the criteria specified.
501.19.1 Sampling Units and Sampling Requirements: The pavement thickness
characteristics will be determined from an analysis of measurements made by non -destructive methods in accordance with MP 700.10.01. These measurements will be made by the Division with a frequency of one measurement from each sampling unit as defined. If the accuracy of a result from the non -destructive method is questioned by the Engineer, then a core shall be taken from the location at which the non -destructive measurement was t aken. The subject core thickness shall then be used to verify the measurement from the non -destructive method, and if a difference of more than ¼ inch between the two measurements exists, the core measurement shall be used for acceptance purposes, instead of the non -destructive method measurement.
501.19.1 1-Highway Proper: The total length of paving lane in linear feet in the
highway proper shall be divided by 500 to determine the largest whole number which shall be the number of sampling units in the highway proper. The width of the sampling unit shall be the width of the paving lane, and the length of the sampling unit shall be determined by dividing the total length of paving lane in linear feet in the highway proper by the number of sampling units determined in the manner set forth. When paving lane width exceeds twenty -four ( 24) feet, the Division may establish shorter sampling units. When the number as determined above is less than ten ( 10), the total length of the paving lane in linear feet shall be divided into ten (10) equal sampling units.
501.19.1 2-Auxiliary Features: Intersections, entrances, exits, crossovers, ramps,
etc., may be considered individually or collectively so as to fo rm sampling units most nearly the length previously established in the highway proper.