Learning  Objective: Recognize the  principles  of  asphalt finishers  (pavers). 12–61. The primary job of an asphalt paver  is  receiving  and  spreading asphalt in a predetermined uniform length,  width,  thickness,  and shape. 1. True 2. False 12-62. Hot-mix asphalt that is dumped in the hopper is transported to the distributing augers in what way? 1. It is carried by the vibrating screed 2. It is pushed by the tamper bar 3. It is pushed by the bevel end plates 4. It is carried by the feed conveyor 12–63. During paver operations, which of the  following  conditions  can  cause unnecessary  movement  of  the  paver that  is  transmitted  to  the  screed and results in an uneven pavement surface? 1. Low tire pressure or loose crawler  tracks 2. The screed is too hot 3. The vibratory unit is not set  properly 4. Oversteering  by  the  operator 12-64. A paver engine is not working properly and a power lag occurs that  causes  a  temporary  failure  of the  vibrators  or  tamping  bars  in the screed unit. What condition results  from  this  failure? 1. A  stretch  of  pavement  that is less dense or contains slightly  less  material 2. A  stretch  of  pavement  that has  more  material 3. The fines in the asphalt mix  separate 4. The  asphalt  mat  is  higher in that area after it is rolled 12–65. During  operations,  the  speed  of the conveyor and the opening of the control gates at the back of the hopper of the paver should be adjusted to allow just enough mixture to be delivered to the augers so they are operating what minimum  percentage  of  the  time? 1. 65% 2. 75% 3. 85% 4. 95% 12-66. What  component  of  the  asphalt paver  irons  the  asphalt  mixture surface,  leaving  the  hot  mat thickness at a depth that conforms with job specifications? 1. The screed 2. The tamper 3. The  conveyor 4. The hopper 12-67. Tamping  bars  and  vibratory mechanisms  are  designed  to  perform which of the following functions? 1. Strike off and heat the asphalt 2. Strike off and adjust the amount  of  asphalt 3. Strike off and compact the asphalt 4. Strike off and roll the asphalt 12-68. What  condition  results  if  the tamping bar travels too far downward  below  the  screed  plate on a tamping bar type of screed? 1. The  hot-mix  builds  asphalt upon the screed face and this condition tends to scuff the surface of the mat 2. The  hot-mix  asphalt  decreases in thickness and the surface pits 3. Overcompaction   occurs resulting in too thin of a mat 4. The tamper over compacts, crushing  the  aggregate  and causing the mat to break apart 95