KANSAS DEPARTMENT OF TRANSPORTATION SPECIAL PROVISION TO THE STANDARD SPECIFICATIONS, 1990 EDITION

Transcription

1 Sheet 1 of 7 KANSAS DEPARTMENT OF TRANSPORTATION SPECIAL PROVISION TO THE STANDARD SPECIFICATIONS, 1990 EDITION SECTION PORTLAND CEMENT CONCRETE PAVEMENT Page 266, subsection.01. Delete the (**) footnote and replace with the following: ** No entry denotes concrete pavement with mesh and dowel assemblies. ** "Plain" denotes concrete pavement without mesh and dowel assemblies. ** NRDJ denotes non-reinforced dowel jointed PCCP. Page 266, subsection.02. Delete the following: Silicone Joint Sealant Section 1500 Add the following to this subsection: Preformed Elastomeric Compression Joint Seals Section 1500 Cold Applied Chemically Cured Joint Sealant Section 1500 Hot Type Joint Sealing Compound Section 1500 Page 268, subsection.03(c). Delete the second paragraph of this subsection and replace with the follow: No tractive forces shall be applied to the slipform paver except that which is controlled from the machine. The subgrade or surface of the subbase over which the tracks of the paver will travel should be trimmed to grade. If the Contractor s equipment or method of operation requires the subbase to be wider than shown on the Plans, the Contractor shall place additional material to provide an adequate surface for the tracks of the paver. If additional subbase material is placed, this material shall be removed and disposed of by the Contractor upon completion of the paving operations. Additional subbase material furnished, placed, compacted, trimmed, and removed and disposed of by the Contractor shall be subsidiary to other items of the Contract. The surface shall not be disturbed by other equipment. The paver shall be operated in a continuous operation. Frequent starting and stopping of the paver shall not be allowed. If it is necessary to stop the forward movement of the paver, the vibrator and tamping elements shall be stopped immediately.

2 Sheet 2 of 7 Page 268, subsection.03(c). Add the following to this subsection. The following shall apply for Slip Form Paving: (1) The maximum width paving in a single operation shall not exceed 7.4 m. (2) Paving of 7.4 m mainline pavement shall be in a single operation. (3) If the Plans show a crown section on multi-lane pavement, the two lanes forming the crown shall be paved in a single operation. As an exception, the Contractor may pave the two lanes forming the crown plus a 1.8 m shoulder (9.2 m maximum) in a single operation when approved by the Engineer; approval will be based on the performance of the Contractors operation. An odd number lane and shoulder may be paved at the same time provided the paving width does not exceed 7.4 m. (4) Ramps and auxiliary lanes/shoulders may be placed in one operation provided the paving width does not exceed 7.4 m. (5) As an exception to the 7.4 m maximum paving width, KDOT s 9.2 m pavement design (7.4 m mainline plus 0.9 m shoulders) shall be paved in one operation. Page 280, subsection.03(h)(8.4). Delete this subsection and replace with the following: (8.4) Sealing Joints. The location, size and configuration of the joint shall be shown on the Plans. Unless otherwise shown on the Plans or in the Contract, transverse pavement joints shall be sealed with preformed elastomeric compression joint seals; longitudinal pavement joints shall be sealed with either a cold applied chemically cured joint sealant or a hot type joint sealing compound. Only one type of longitudinal joint sealant shall be used on a project, unless otherwise approved by the Engineer. Joints shall be sealed prior to opening to traffic. For construction traffic see subsection.03(j)(3.1). Page 280, subsection.03(h)(8.5). Delete the first sentence of this subsection and replace it with the following: Joints shall not be sealed until they are clean and dry and the pavement has attained the age recommended by the manufacturer of the sealant. For preformed elastomeric compression joint seals, concrete that has reached an age that permits proper sawing and cleaning without causing deterioration of the joint edges and joint faces, is considered acceptable for seal installation. Page 280, subsection.03(h)(8.5). Add the following to this subsection: (8.51) Preformed Elastomeric Compression Joint Seals. The Contractor shall arrange for a technical representative of the joint seal manufacturer to be present during installation of the joint seal to provide guidance on cleaning and preparation of the joint, and installation of the seal. The manufacturers technical representative shall remain on the project until such time that

3 Sheet 3 of 7 the Contractors personnel and KDOT inspectors have been thoroughly trained in the proper installation of the joint seal. Prior to installing preformed joint seals, clean the seal reservoir of the transverse joint extending to at least one half inch deep from the joint edges using water or sand blasting equipment. Use a multiple pass technique until the surfaces are free of dirt, curing compound, or any residue which might prevent ready insertion of the seal, or uniform contact with the concrete. (Note: These seals are held in place by compressive forces and friction acting on the faces of the joint, not chemical bonding as with other joint sealants.) After final cleaning, and immediately prior to installing the seal, blow out the joint seal reservior with compressed air until it is free of debris and visible water. Under normal construction procedures, seal transverse joints full width with no splices made in the preformed joint seal. However, under phased construction or widenings, where the lanes placed earlier have been opened to traffic, the preformed joint seal may be spliced at the construction joint. When the existing seal is peeled back to saw the construction joint, it should be cleaned, lubricant/adhesive reapplied, and reinstalled as soon as possible to prevent damage. After the new seal is installed, place the longitudinal joint sealant through the intersection with the transverse joint, with the transverse seals butted in. Ensure that the longitudinal sealant encases and seals the ends of the preformed seals. The joint seal shall be installed by a machine especially designed to compress and install the sealant in an upright position, without cutting, nicking, distorting or otherwise damaging the seal. Lubricant shall be applied to the concrete or the preformed seal (or both), and the seal shall be installed in a substantially compressed condition. The top of the seal shall be placed, at a depth recommended by the manufacturer, below the finished surface of the pavement. The method of installation shall be such that the joint seal will not be stretched or compressed more than 3 percent of the length, unless otherwise stated in the manufacturer s written instructions. The method of installation will be checked for stretching or compression by comparing the distance between two marks on the surface of the seal measured before and after installation. If the check indicates stretching or compression beyond the limits stated above, the method of installation shall be modified to correct the situation. The Contractor may proceed slightly out of specification for a short distance under the supervision of the manufacturer s technical representative, while making corrections and adjustments to return to specification limits. This material may remain in place provided the stretching does not exceed 5 percent and the Contractor makes a good faith effort to correct the problem. Once the machine is in proper adjustment and the installation is proceding satisfactorily, further checks (approximately every hundred joints) will be made to assure proper installation. Any joint seal not conforming to the above stated limits of installation shall be removed and replaced with new material. No seal shall be reused after being removed for any reason. Joint enlargement. The 17.5 mm seal is intended to be installed in a 9.5 mm sawed joint. If it becomes necessary to enlarge the joint width, then the 17.5 mm seal may no longer be the proper size for the opening. Contact the Bureau of Materials and Research for assistance in determining the proper size in such instances. (8.52) Cold Applied Chemically Cured Joint Sealant and Hot Type Joint Sealing Compound. The Contractor shall arrange for a technical representative of the joint sealant

4 Sheet 4 of 7 manufacturer to be present during installation of the joint sealant. The manufacturers technical representative shall remain on the project until such time that the Contractors personnel and KDOT inspectors have been thoroughly trained in the proper installation of the joint sealant. Page 280, subsection.03(h)(8.6). Delete this subsection in its entirety and replace with the following: (8.6) Equipment. The backer rod shall be installed utilizing a device which will place the rod uniformly at the depth shown on the plans. The joint sealant shall be applied by an approved mechanical device from inside the joint in such a manner which causes it to wet the joint surfaces. Any failure of the joint material in either adhesion or cohesion will be cause for rejection, and the joint shall be repaired to the Engineer s satisfaction at the Contractor s expense. Type I silicone sealant is not self leveling and will not position properly in the joint under its own weight; therefore, the sealant surface shall be tooled using the appropriate tool to produce a slightly concaved surface approximately 6 mm below the pavement surface as shown on the Plans. Tooling shall be accomplished before a skin forms on the surface. The use of soap or oil as a tooling aid will not be permitted. (8.61) Equipment for Hot Type Joint Sealing Compound. The Contractor shall use a double boiler type melter with a permanently attached temperature gauge to continuously verify sealant temperature in the material tank. Units with a solvent flush system for clean out are not acceptable, because of the risk of solvent contamination to the sealant. The Contractor shall use a melter with a heat chamber for hose storage and valve heating, or an air flush system to eliminate the need for a solvent flush clean-up system. The unit shall provide material tank mixing with a reversible paddle type agitator in a vertical tank configuration. The Contractor shall use units similar to those purchased by KDOT Maintenance under Spec: MS 168. The Contractor shall completely clean out the unit when changing brands of material, or if the material exhibits any sign of changes in application characteristics, polymer or oil separation, balling or any other signs of jelling. The unit may contain compatible material from a previous job at start-up. The Contractor shall provide the Engineer a certification covering the material in the unit, including the manufacturer, type, etc. Material which cannot be identified and certified must be completely cleaned out before start-up. Page 284, subsection.03(j)(3.1.2). Delete the paragraph and replace with the following: (3.1.2) The flexural strength of the pavement shall meet or exceed 3.1 MPa. The flexural strength of the pavement shall be determined by testing flexural strength specimens utilizing the third point loading method. Page 287, subsection.04(a). Delete the first paragraph and replace with the following:

5 Sheet 5 of 7 It shall be the responsibility of the Contractor to repair any broken, cracked or spalled panels as specified hereinafter at no cost to the Department. The joints of the repaired or replaced panels shall be properly sealed. Page 289. Add the following as new subsection.04(d): (d) The following applies to new non-reinforced dowel jointed PCCP: (1) Transverse and Diagonal Cracks. The Contractor shall remove and replace pavement panels containing any transverse or diagonal crack in accordance with the following: A full depth saw cut shall be made in the abutting panel nearest to the crack. The full depth saw cut shall be made parallel to the contraction joint and just clear of the basket assembly. Holes shall be drilled and dowel bars inserted to make a new contraction joint. The dowels shall be the same size and spaced the same distance as shown on the Plans. Bar holes shall e 6 mm mm larger than the diameter of the bar and filled with epoxy or Portland cement grout. The free ends of the bars shall be supported until the epoxy or grout has set to assure proper alignment of the bar. The free ends shall be greased. A second full depth saw cut shall be made in the cracked panel on the opposite side of the crack and parallel to the contraction joint; however, no patch section shall be less than two meters in length. A construction joint shall be installed by drilling 19 mm diameter holes 300 mm deep on 450 mm centers and installing #12 x 610 mm deformed tie bars in the holes. An epoxy grout or Portland cement grout shall be placed in the back of the hole before inserting the bar. Sufficient grout shall be used to fill the annular space around the bar. A doweled contraction joint shall be substituted for the construction joint if the distance between contraction joints in the patched pavement would otherwise exceed 5.5 m at any location. The longitudinal joint tie bars shall be sawed off at the longitudinal joint. Holes shall be drilled midway between the existing bars and tie bars inserted to make new tied longitudinal hinged joint. Tie bars shall be of the same size and spacing as shown in the Plans. Bar holes shall be 6 mm mm larger than the diameter of the bar and filled with epoxy or Portland cement grout. (2) Longitudinal Cracks. The Contractor shall repair or remove and replace pavement panels which contain longitudinal cracks in accordance with the following: Longitudinal cracks that are within 75 mm of the planned longitudinal joint for their entire length shall be repaired with a partial depth patch as specified for spalls in section (a) of this specification; except the transverse dimension of the patch shall be 150 mm. Longitudinal cracks that are >75 mm but <150 mm from the planned longitudinal joint for the entire length shall be injected with epoxy or its entire length. Longitudinal cracks that are 150 mm or more from the planned longitudinal joint shall be repaired by removing and replacing pavement panels in accordance with the requirements of paragraph (d)(1) of this specification.

6 Sheet 6 of 7 Page 295, subsection.08(a). Delete the third paragraph and replace with the following: When the average thickness of the pavement determined as hereinafter provided, is deficient by more than 5 mm as based on the thickness required by the typical cross sections shown on the Plans or designated in the Contract, a price adjustment for deficient concrete pavement thickness will be made in accordance with these Specifications. Payment for "Concrete Pavement Thickness Deficiency" will be shown as an added item to the Contract M&R (JLC) Hot Type Joint Sealing Compound LBS 90M Preform Elastomeric Comp Jt Seal LNFT Cold Applied Chem Cured Jt Seal t GALS 90M-97