R 2-27-98

RUBBLIZING EXISTING PORTLAND CEMENT CONCRETE PAVEMENT

    The Standard Specifications are revised as follows:

SECTION 305, BEGIN LINE 3, INSERT AS FOLLOWS:
   305.01 Description. This work shall consist of reconditioning an existing road or an existing surface, considered as a base, by rubblizing and compacting, repairing, patching, widening, sealing

SECTION 305, LINE 59, DELETE AND INSERT AS FOLLOWS:
   305.04 Blank. Rubblizing Existing Portland Cement Concrete Pavement. The existing pavement shall be rubblized with a self-contained, self-propelled resonant frequency pavement breaking unit capable of producing low amplitude, 900 kg (2000 lb) blows at a rate of not less than 44 per sec or with a self-contained, self-propelled, multiple headed, impact hammer with the heads directly adjacent to each other and the lift height of each head independently adjustable. The sequence of impacts shall be on a random basis. The unit shall be equipped with a water system to suppress dust generated by the operation.

    The operating speed of the unit shall be such that the existing pavement is reduced into particles ranging from sand sized to pieces not exceeding 150 mm (6 in.) in the largest dimension, the majority being a nominal 25 to 50 mm (1 to 2 in.) in size. The concrete from the surface to the top of the reinforcement shall be reduced to the 25 to 50 mm (1 to 2 in.) size to the fullest extent possible. Continuous coverage, overlapped if necessary, with the breaking shoe or impact hammers shall be required. Additional passes of the resonator or multiple headed impact hammer may be required if larger sizes remain above the reinforcement.

    Subsurface drains shall be installed along the edges of the pavement prior to the rubblization. Rubblizing shall begin at the edge of pavement and proceed to the center of the pavement. The first lane's rubblization shall extend 150 mm (6 in.) into the adjoining lane.

    Prior to placing the HMA mixtures, the complete width of the rubblized pavement shall be compacted by means of a vibratory steel wheel and pneumatic-tired rollers in the following sequence; two initial passes with a vibratory roller, two passes with a pneumatic-tired roller, and then four final passes with a vibratory roller. The last two passes shall be on the same day and as close as possible to the paving operations. When the multiple headed impact hammer is used, a Z-pattern steel grid vibratory roller shall be used for additional particle break down to the satisfaction of the Engineer. This roller shall be a self-contained, self-propelled vibratory steel wheel roller with a Z-pattern grid cladding bolted to the surface of the drum. The steel grid vibratory roller shall have a minimum gross weight of 9 metric tons (10 tons).

    The rolling equipment shall be in accordance with 408.03. The vibratory roller shall be operated in the vibration mode at a speed not to exceed 1.8 m (6 ft) per sec. All depressions, 25 mm (1 in.) or greater in depth from that of the immediate surrounding area, that result from the rubblizing or compaction effort shall be filled with filler aggregate No. 53 and struck off level with the surrounding area. Filled depressions shall be compacted with the same roller and compactive effort previously described.

    Reinforcement in the rubblized pavement shall be left in place. However, all reinforcement exposed at the surface as a result of rubblizing or compaction operations shall be cut off below the surface and removed from the site. All loose joint fillers, expansion material, or other similar materials shall also be removed from the rubblized surface.

    Except at restricted crossover and ramp crossings, traffic will not be allowed on the rubblized pavement before the HMA base or intermediate courses are in place. Rubblized material dislodged by construction traffic shall be removed from the pavement. Not more than 48 h shall elapse between rubblizing and placement of the initial HMA course. However, in the event of rain, this time limitation may be waived to allow sufficient time for the rubblized pavement to dry to the satisfaction of the Engineer. Crossover and ramp crossings shall be maintained in the same compacted state as other areas until the initial HMA course is placed.

    The preceding rubblizing operations shall be scheduled after widening or shoulder work has progressed up to the elevation of the existing pavement grade. These areas can then be utilized to support the breaking unit while the existing pavement is being rubblized. Shoulders can then be completed in conjunction with the placement of HMA pavement courses over the compacted rubblized pavement.

    A joint shall be saw cut full depth or load transfer devices shall be severed at an existing joint on ramps or mainline where the rubblizing abuts concrete pavement which is to remain in place.

SECTION 305, AFTER LINE 286, INSERT AS FOLLOWS:
Rubblized portland cement concrete pavement will be measured by the square meter (square yard) of rubblized pavement. The quantity of filler aggregate No. 53 will be measured by the Mg (ton) of aggregate placed.

SECTION 305, AFTER LINE 289, INSERT AS FOLLOWS:
   Rubblized portland cement concrete pavement will be paid for at the contract unit price per square meter (square yard) for rubblized pavement. Filler aggregate, 53 will be paid for at the contract unit price per megagram (ton) complete in place.

SECTION 305, AFTER LINE 303, INSERT AS FOLLOWS:
      Aggregate, 53 .................................Mg (TON)

SECTION 305, AFTER LINE 306, INSERT AS FOLLOWS:
      Rubblized Pavement .........................m2 (SYS)

SECTION 305, AFTER LINE 321, INSERT AS FOLLOWS:
   The costs of furnishing all labor, materials, and equipment necessary to rubblize, suppress dust, cut and remove exposed reinforcement, cut and remove joint fillers or similar materials, saw cutting of the pavement, severing existing joints, compacting and maintaining the compacted condition of the rubblized pavement shall be included in the cost rubblized pavement.

    The costs of furnishing, hauling, placing, leveling, and compacting the aggregate to fill the depressions in the rubblized pavement shall be included in the cost of aggregate, 53.

 

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