NOTE: Do NOT use a detergent that is designed tobreak down grease or oil, as this will break down thepetroleum products used in the bituminous mix.NOTE: Ensure roller tires and drums are free ofdebris, such as sand, mud, dirt, and so forth, beforerolling a hot bituminous mix.CAUTIONAvoid prolonged skin contact with andinhalation of vapors from bituminous opera-tions.When you are rolling bituminous materials, therollers should move at a slow, uniform speed with thedrive wheels positioned toward the paver. The speedshould not exceed 3 mph for steel-wheeled rollers or 5mph for pneumatic-tired rollers. Asphalt rollers must bekept in good condition and should be capable of beingreversed without backlash. The line of rolling should notbe suddenly changed or the direction of rolling suddenlyreversed, thereby displacing the mix. Any pronouncedchange in direction should be made on stable material.Rolling hot bituminous mix is done in the followingorder:1.2.3.4.5.Transverse jointsLongitudinal joints (when adjoining a pre-viously placed lane)Breakdown or initial rollingIntermediate or second rollingFinish rollingAs a guide, longitudinal joint and edge rollingshould be performed directly behind the paver;breakdown rolling less than 200 feet behind the paver;intermediate rolling 200 feet or more behind thebreakdown rolling; and finish rolling as soon as possiblebehind the breakdown rolling.Transverse JointsWhen a transverse joint is placed next to anadjoining lane, the first pass is made with a steel-wheeled roller moving along the longitudinal joint for ashort distance. The surface is then straightedge andcorrections made if necessary. The joint is then rolledtransversely with all except 6 inches of the wheel widthon the previously laid material (fig. 11-49). Thisoperation should be repeated with successive passesFigure 11-49.-Rolling a transverse joint.covering 6 to 8 inches of fresh material until the entirewidth of a roll is on the new mix.During transverse rolling, boards of properthickness should be placed at the edge of the pavementto provide the roller a surface to drive on once it passesthe edge of the hot bituminous mat. If boards are notused, the transverse rolling must stop 6 to 8 inches shortof the outside edge in order to prevent damage to theedge. The outside edge then must be rolled out duringlongitudinal rolling.Longitudinal JointsLongitudinal joints should be rolled directly behindthe paving operation, Only 4 to 6 inches of the rollerwidth should ride on the newly placed mix (fig. 11-50).The rest of the roller should ride on the previouslycompacted side of the joint. With each subsequent pass,more and more of the roller width is placed on the mixuntil the entire width of the roller is on the newly placedmat.When rolling a longitudinal joint with a vibratoryroller, the roller drum extends only 4 to 6 inches on thepreviously compacted lane with the rest of the drumwidth riding on the newly placed mat. The rollercontinues to roll along this line until a thoroughlycompacted, neat joint is obtained.Longitudinalcold joint.joints can be categorized as a hot or11-26
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