Research On Multiple Application Technology Of High Performance Paving Stress Absorbing Layer

Cement concrete pavement have gotten rapid development in our country because of itshigh strength, durability and other advantages, so asphalt overlayers are essential to therehabitlitation project of existing concrete pavements.However, due to design, constructionand materials，the occurrence of reflective cracking often happens and has become the majordisease of rehabitlitation project which affects the performance of overlayer pavementsseriously.On the basis of comprehensive analysis of research home and abroad, combing withYantai-Weihai Expressway, the paving stress absorbing layer was selected as research objectand overlay structure with stress absorbing layer, material index of stress absorbing layer,construction technology and the ability to relieve reflective cracking were analysed in order toput forward specifications and material requirements of a high anti-cracking stress absorbinglayer.Six aspects as follows have been analysed in this dissertation:(1) Research on reflectivecracking and overlay structure home and abroad and the application of stress absorbing layerin overlay structure.(2)Combining with fatigue test and three-dimensional finite elementmethod, the effect of thickness and modulus of overlay and stress absorbing layer werestudied, the optimum pavement structure was put forward.(3) Using three-dimensional finiteelement method combing with fracture mechanics,intial crack was implanted in stressabsorbing layer in advance,and the stress absorbing layer cracking criterion of the differentload positions, temperature load, coupling condition of temperature and load were taken andthe actual required anti-cracking indicator of stress absorbing layer was put forward.(4)Inorder to improve the anti-craking performance of stress absorbing layer,effects of mineralaggregate, asphalt, gradation on anti-craking performance of stress absorbing layer wereanalyzed through experiment, high temperature stability,low temperature stability,waterstability and bond strength between layers were analysed, the technical indicators of materialand gradation that require the anti cracking ability wee put forward.(5)Existing concretepavement structural treatment standard, superficial treatment standard were identified throughthe test road construction,after a long-term observation of the reflective cracking, reflectivecracking happening rate (FSL) and anti-cracking degree of stress absorbing layer (ZLD) wereput forward as an indicator to evaluate the effect of stress absorbing layer for the first time.