Study On Low Temperature Crack-resistance Of Asphalt Pavement Using Transverse Contract Joint In Cold Region

Based on the investigation of the transverse cracks of several highways in cold regions(mainly in Heilongjiang Province),it is found that the low temperature cracking of asphalt pavement in cold region is widespread.Even the use of raw materials and reasonable design parameters of high quality and strict construction requirements and other security measures,still can not avoid the crack in low temperature,but the low temperature cracks will expand to a certain extent,can carry on the pouring operation maintenance etc..It has been proved that even if the low temperature crack is repaired,it can not prevent the occurrence of re cracking.Cold asphalt pavement due to the influence of low temperature shrinkage crack of asphalt pavement,but at the same time in the low temperature structure layer(asphalt surface layer)strength increases rapidly,the modulus of resilience can reach tens of MPA,asphalt mixture in this state can be regarded as a rigid material,and the asphalt pavement under low temperature can be seen as "rigid pavement".As a typical rigid pavement,cement concrete pavement is also facing the same problem,but it is through the establishment of the method of lateral contraction.The similarity between two kinds of pavement,the asphalt pavement application of theory of elastic thin plate under low temperature,the asphalt mixture dynamic relationship based modulus,temperature shrinkage coefficient and surface friction coefficient and temperature,the cold asphalt pavement temperature stress calculation formula.When the ultimate tensile strength of known pavement materials,can quickly get cracking temperature of pavement,combined with the friction coefficient of K base asphalt pavement of the obtained slip distance range of the road,the distance is set transverse contraction joint theory of cold asphalt pavement segment distance.Simulation and calculation of asphalt pavement in Heilongjiang area the actual cracking statistics distance with advanced ABAQUS software,further revised setting transverse contraction joint cold asphalt pavement segment distance,increasing its theoretical support and practical basis.In order to get a more comprehensive set of other parameters of the transverse shrinkage joint,combined with the cement pavement temperature shrinkage crack parameters and SHRP in pouring related research,the asphalt pavement transverse contraction joint width and depth of the recommended reasonable.So,through the above research and exploration,the cold asphalt pavement by using the elastic thin plate theory calculation of low temperature cracking and crack spacing in asphalt pavement is feasible,the transverse contraction joint spacing is reasonable,contraction joint spacing and depth is on the basis of reality.After filling and shrinkage crack of asphalt pavement in cold region is set timely,to avoid the disadvantages of late reperfusion seam cracking theory,combine between asphalt mixture and filling materials more closely integrated,reducing the risk of low temperature cracking of asphalt pavement,and provides a new method for solving the cracking mechanism of asphalt pavement at low temperature,change from passive to active,increased with age and performance of bituminous pavement.