Mechanical Analysis Of Antireflective Cracking For Joint Section Of New And Existing Pavement Reinforced With Double Twisted Steel Wire Mesh

In the existing road widening project, flexural and shear stress will be caused in the pavement layer of the joint section of new and existing pavement when the differential settlement between the new and existing subgrade is too large, which in order to the reflective cracking. So the subject introduces a new double twisted steel wire mesh reinforced in the joint section of new and existing pavement technology, and uses the method of three-dimensional finite element analyzing corresponding mechanical response and reinforcement effect, expect to increase the ability of antireflection cracking in the joint section of new and existing pavement.1) Combining the inter-provincial highway reconstruction project from Chengguan Town of Kaihua County in Zhejiang Province (Dushan) to Jiangxi Province (Baishaguan), five different load positions are selected, when the load is on the side of the new pavement and the tire edge corresponding of joint section, the surface deflection and tensile stress are the biggest, at this time, the load is in the worst load position.2) The mechanical response influence law of the 4 shemes is analysised with a or no crack in the joint section of new and exsiting pavement in the worst load position, which is double twisted steel wire mesh laying between base and the exsiting pavement (or subbase) (Scheme One), binder course and base (Scheme Two), binder couse and surface couse (Sheme Three), and without unreinforced. The following conclusions are obtained. When the double twisted steel wire mesh lays between base and the existing pavement, the vertical displacement of pavement structure is the least. The antireflcetion cracking performance of the Scheme One, the Scheme Two and the Scheme Three is more obvious when there is crack in the new and existing pavement, their crack resistance compared with the situation without crack, increase by 38.4%, 11.7% and 10.6%. The cracking width in the joint section of new and exsiting pavement of the Scheme One, the Scheme Two and the Scheme Three are at the maximum 0.13m away from the pavement surface, and corresponding increase by 0.01%, decrease by 0.01% and increase by 0.02% compared with the unreinforced. The best laying position of the double twisted steel wire mesh is between binder couse and surface couse.3) While double twisted steel wire mesh (Scheme Two), geotextile (Scheme Four), glass fiber grid (Scheme Five), geogrid (Scheme Six) are laying between binder course and base, the mechanical response influence law of which is analysised when there is crack in the joint section of new and exsiting pavement in the worst load position. The following conclusion is obtained. The vertical displacement at joint section of pavement surface of the Scheme Two, Scheme Four, Scheme Five and Scheme Six, decrease by 13.8%, 10.5%, 11.7% and 12.9% compared with those which are unreinforced. The biggest tensile stress at bottom layer of the surface course decrease by 8.3% compared with the unreinforced. The biggest bottom layer tensile stress of the binder course decrease by 0.0%, 0.0%, 20.7% and 17.2% in ture compared with the unreinforced, the biggest tensile stress at bottom layer of the base and subbase of Scheme Two decrease by 18.6% and 5.3%, when other schemes increase. The biggest cracking width of Scheme Two, Scheme Four, Scheme Five and Scheme Six decrease by 0.01%, 0.00%, 0.01% and 0.02% compared with the unreinforced; the best reinforced materials is double twisted steel wire mesh.In brief, the research results provide a scientific basis for the design of double twisted steel wire refinforced in the joint section of new and existing pavement and improve antireflection cracking capabilities.