1925 (#1403-1607) - Laserfiche WebLink

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are eliminated. The motion of the roller shall at all times be slow, to avoid displacement of the hot mixture and any dis- placements oocuring as a result of reversing the direction of the roller or by any other cause, shall at once be corrected by the use of rakes ~nd by the addlt~on of fresh mixture when required. Rolling sha~l proceed ~t an average rate of not to exceed two hundred (200) square yards per hour per roller and shall continue until no further compression is possible. The specific gravity of the material after rolling shall be not less than ei~ht2-elght (88) percent of the combined rock, sand and stone dust as found in the mixture. To prevent adhesion of the surface mixture to the roller, the wheels shall be kept properly moistened but excess of either water or oil will not be permitted. (b) Along curbs, headers and similar structures, and at all places not accessible to the roller, the surface mixture shall be thoroughly compacted and Joints sealed with hot tampers. (c) The surface of the pavement, after compression shall be smooth and true to the established crown ~nd grade. Any defective places shsll be immediately remedied by removin tbs surface mixture which sh~l be immediately compacted to conform with the surroundin~ area. S~CTION 8. JOINTS. Placing of tbs surface course sha~l be nearly con- tinuous as possible, and the roller shall pass over tbs un- pr~ected end of the freshly laid mixture only when the layin~ of the course is discontinued for such length of time as would permit the mixture to become chilled, In all such cases, in- cluding the formation of Joints as hereinbefore specified, provision shall be made for proper bond with new surface mix- ture by cutting or trimming back the joint so ~s to expose an unsesled or granular surface for the fn~ specified depth of the e~urse. At the end of each day's work on surface misture Joints shall be formed by laying ~nd ro~l~ng against boards, of tbs thickness of the compacted mixture, placed ~cross the entire width of the pavement, or by s,~ch other method as may be aoproved by the Superintendent of Streets. When the layln of th~ surface course mixture is resumed, the exposed edge of the Joint ~hall be painted with a thin Coat of hot asphalt ce- ment or asphalt cement thinned wit~ naphtha, and the fresh mixture shall be raked against the Joint, thoroughly tamped with hot tampers, and ro~ed. Not smoothing irons may be use~ for sealing Joints, but in such case, extreme care ~hall be exercised to avoid burning the surface. SECTION 9. SEAI COAT. (s) Immediately ~fter the pavement has been pacted as above specified, ~ shall be swept clean of all