Effects Of Freeze-Thaw Cycles On The Fracture Behavior Of Epoxy Asphalt Concrete

Cracks are usually observed on steel bridge deck epoxy asphalt pavement. During the low temperature condition in winter, the water and snow on the pavement will lead to the decrease of the anti-cracking ability of epoxy asphalt pavement under the repeating freeze-thaw cycle. Even though the moisture damage of asphalt pavement has been studied by many researchers, the disease of epoxy asphalt pavement leaded by freeze-thaw cycle still has not been effectively solved. So the fracture behavior of epoxy asphalt concrete under freeze-thaw cycle is studied in this paper.First of all,through the investigation of relevant papers and test schedules, the 3-point bending test of epoxy asphalt concrete beam under different freeze-thaw cycles has been designed and the elastic modulus and fracture energy have been calculated. In this paper, the finite element models of 3-point bending test of epoxy asphalt concrete single edged notch beam under different freeze-thaw cycles have been built; the plane-strain fracture toughness (KIC), ductile fracture toughness CIC), ultimate tensile strength and ultimate stretching strain have been calculated; the influence of freeze-thaw cycle on the fracture parameters and the cracking direction of epoxy asphalt concrete.Secondly, the finite element models of 3-point bending test of epoxy asphalt concretecompound beam and composite beam with crack have been established; the fracture toughness of epoxy asphalt concrete under different freeze-thaw cycles by the finite element models; the inter-laminar shearing stress, ultimate transverse tension stress, ultimate transverse tension strain and anti-cracking bearing capacity of the epoxy asphalt concrete pavement structure with crack have been calculated when it is at the ultimate condition of fracture; the influence of freeze-thaw cycle on the mechanical properties of epoxy asphalt concrete pavement structure with crack.Finally, cluster analysis method has been adopted to analysis the similarity of the 6 indexes of the anti-cracking ability of epoxy asphalt concrete and the hierarchical model, which is to evaluate the anti-cracking ability of epoxy asphalt concrete, has been established; the weight vector of the filtered indexes of the anti-cracking ability of epoxy asphalt concrete has been obtained by one factor analysis of variance; the anti-cracking ability of epoxy asphalt concrete under different freeze-thaw cycles has been evaluated by fuzzy comprehensive evaluation method; according to the evaluation results, the maintenance strategy of epoxy asphalt concrete with crack has been proposed. Results indicate that in order to assure the anti-cracking ability of epoxy asphalt concrete,the suitable maintenance frequency of steel bridge deck epoxy asphalt concrete pavement structure should be once a month (30 days) at the low temperature condition in winter.