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Calculation and Analysis of Load Stress on Typical Semi-rigid Base Asphalt Pavement |
HAO Guan-jun |
China Railway Majoy Bridage Reconnaissance & Design Institute Co., Ltd, Nanjing Jiangsu 210031, China |
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Abstract The linear elastic Bisar software is used to calculate the mechanical properties of a typical semi-rigid pavement structure. Based on the concept of structural strength coefficient, the fatigue life of each pavement structure layer is deduced. The results show that: (1) The maximum value of deflection is obtained at x=3r/2, the maximum of the surface stress is obtained at X=r/2 and Y=0, and the peak of the principal (shear) stress at the bottom of the (bottom). (2) At the same time, the horizontal load, road surface deflection and the maximum stress position of the surfacing surface are invariably applied at the same time. The deflection changes little, and the maximum principal stress increases faster than the maximum shear stress. The maximum. (3) The cracking order of structural layer is as follows: shear cracking of surface layer → bending and cracking of surface layer → bending and cracking at the bottom of base layer → Bending and cracking at the bottom of semi-rigid base → bending and cracking at the bottom of the surface layer, the inner edge of single circle is the destroying source of asphalt pavement, and the initial damage is shear (bending) failure. Therefore, the durable pavement Should consider the principle of structural layer cracking from bottom to top, and to prevent the early destruction of the surface layer. (4) The cracking of the base layer will be reflected to the semi-rigid base and surface layer, which is the first step of structural damage, so strengthening The construction quality of the subbase is an important measure to reduce road damage.
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Received: 30 June 2020
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