Study On Porous And Semi-flexible Compound Pavement Structure

Now, traffic safety, comfortable and bearing capacity of pavement structure are required to be at a higher level by drivers. Researchers of the road have designed lots of new pavement materials with different performance, however, the pavement is a combination structure, its performance is not only determined by a structural layer, but also by the entire pavement structure even subgrade. Researchers of road have explored the best combination of pavement structure and got many corresponding results, but the effect isn't significant in generally. Therefore, research on the compound pavement structure has become a hot topic at present.In this paper, combinations of porous and semi-permeable asphalt pavement are determined by the existed result. Change between layers thickness and sliding coefficient are determined by orthogonal design and significance analysis methods, meanwhile defined the impact discipline of design index and the impact of significant factors. it is found that there are not permitted compressive strain on the top of sugared used in the design of asphalt pavement in our country. through the contact layer at the end of tensile stress have a significant impact analysis and verify the necessity to maintain a good contact state between layers; then the best structure of porous and semi-flexible is selected which based on the general scoring of each road composite structures. the optimal structure of pavement is: porous asphalt on top layer + semi-flexible compound asphalt concrete on below layer + stabilized crushed stone base(contain of cement is 5%) + stabilized crushed stone base(contain of cement is 3%) + natural gravel. The bonding slide coefficient between layers from top to bottom is 0.25, 0.25, 0.5; the distribution of shear stress between layers was analyzed with vertical and horizontal load of the standard axle. The max shear stress between layers are found at the outer edge of the wheel, and the poorer contact status between layers, the more forward position, the effect of horizontal load on the shear stress between layers; two bonded materials are selected, pull-out strength and shear strength are measured separately, meanwhile the pull-out strength and shear strength are measured while the bonding layer is saturated; the paving of experiment pavement,quality and detection of noise reduction of the porous and semi-flexible compound is completed; the construction methods,construction machinery, process technology of a porous and semi-flexible compound pavement are preliminary preparation.The research got supported by the transport project "study on porous and semi-flexible compound pavement structure "in Hubei.