Analysis on crack propagation of asphalt bridge deck pavement under water-force coupling action
Cracks in pavement layer of asphalt mixture bridge deck will further cause looseness,pit and other diseases under water-load action.In order to reveal the influence of pore water pressure on the expansion of existing cracks under load,this paper established a finite element model of pavement layer of asphalt concrete continuous box girder bridge deck,and verified the correctness of the finite element model by field dynamic load test,taking dynamic deflection and modal of bridge as indexes.Then,longitudinal cracks are preset at the bottom of the upper layer of the deck paving layer,and the propagation effects of existing cracks on the deck paving layer under water-load coupling are studied by analyzing the variation of stress intensity factor KI and KII at the crack tip.It is found that the change of stress intensity factor(KI)reflects that the action of water pressure can promote the expansion of tensile cracks in pavement layer.The presence of water leads to the increase of KI value by about 50%,and the larger the hydrodynamic pressure is,the faster the expansion rate is.The hydrodynamic pressure has little effect on the expansion of shear cracks,and the stress intensity factor(KII)has little change.However,due to the presence of water,the response time of stress intensity factor becomes longer,so the water will have a continuous impact on the bridge deck paving layer.
万方数据
维普
