4.4 Paver
The paver shall be an approved type of self-propelled mechanical spreader and finisher that is capable of continuous
laying to the required widths and thicknesses, without causing segregation, dragging or other surface defects.
The paver shall be provided with a screed of the tamping or vibratory type, with a suitable heating system, and
adjustable to the required width and thickness.
The paver shall be fitted with automatic sensing devices on both sides, to enable it to follow a joint, a preset grade
wire or a levelling beam (skid), and to maintain the required levels and cambers or cross-falls. Where skids are used,
they shall be approximately 10 m long.
The paver shall be capable of travelling at speeds consistent with all outputs of the mixing plant, and of laying the
asphalt to designed widths of 2,5 m to 6 m in increments of 100 mm and more, and to thicknesses of 15 mm and
more.
4.5 Precoated chip spreader
The chip spreader shall be of a self-propelled type supported on pneumatic tyres that run on hard surfaces outside
the new asphalt being placed, or other approved type, and shall be capable of
a) spreading the pre-coated stone chips uniformly to the full width of the paver at one pass,
b) adjustment to permit variation in the rate of application, and
c) stopping and re-starting without forming a joint-line.
The ribbed slots of the spreader drum shall be suited to the size of aggregate used for pre-coated chips.
4.6 Rollers
4.6.1 General
Enough rollers of each type shall be available on the Site to maintain the required tempo of work. The rollers shall
be equipped with adjustable scrapers for keeping the rolls clean and with efficient means for keeping the rolls wet to
prevent asphalt from sticking to them. Oil or petroleum products shall not be used for wetting the rolls.
4.6.2 Pneumatic-tyred rollers
Each pneumatic-tyred roller shall be of the self-propelled type equipped with smooth pneumatic tyres of uniform size
and diameter. Such a roller shall be capable of varying the average contact pressure, by the adjustment of the ballast
or of the tyre inflation pressure, or of both. The wheels shall be sprung either independently or in pairs, but shall not
wobble, and shall be so positioned that the tracks of the back wheels overlap those of the front wheels. Each roller
shall be so designed and constructed that the tyre pressures do not differ by more than 50 kPa.
The mass of the roller or the tyre pressure, or both, shall be such as to ensure proper compaction and compliance
with the requirements of the specification for surface finish and density.
4.6.3 Flat steel-tyred rollers
Each flat steel-tyred roller shall be a self-propelled three-wheel roller or a two-axle tandem roller. The mass of the
roller and the distribution of the mass over the wheels shall be such as to ensure proper compaction and compliance
with the requirements of the specification for surface finish and density.
4.6.4 Vibratory rollers
Suitable approved vibratory rollers may be used on the surface course, provided that the roller characteristics are so
controlled that no distress, cracks or surface irregularities occur.
4.7 Miscellaneous equipment
Sufficient equipment for handling and hauling aggregate, bituminous binder and asphalt shall be provided to ensure
continuous operation of the paver. The Contractor shall have available all the ancillary equipment and hand tools,
thermometers, etc., necessary to carry out the work efficiently. In addition, the Contractor shall install a suitable
weighbridge if such a facility is not available at the plant site.
5 Construction
5.1 General requirements
5.1.1 Preparation of surface
The surface shall be prepared as follows:
a) for priming: the base or subbase, as the case may be, shall be thoroughly swept by means of a mechanically
driven broom and hand brooms, as necessary, until all loose soil binder and all foreign materials have been
removed. In the case of base, the surface shall be swept until the top surface of the stones is exposed. Any
superficial film of soil binder that might have formed on the surface during watering and rolling shall be removed
completely; and
b) for asphalting: immediately before a tack coat or asphalt is applied, the surface shall be broomed and cleaned
of all loose or deleterious material. Where the asphalt is to abut against kerbs, channels or manhole frames, the
vertical face of each such kerb, channel and frame shall be cleaned to a depth (below finished level) of at least
the thickness of the asphalt. 原件下载： 
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