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为弥补水泥混凝土板沥青铺装层间剪切疲劳寿命设计方法的不足,通过不同水环境、正压力条件下沥青混凝土及其与水泥混凝土板层间的抗剪强度和剪切疲劳试验,结合水泥混凝土板沥青铺装结构的三维有限元计算,探讨了水和超载对水泥混凝土板沥青铺装层间剪切疲劳寿命的影响。利用自行研制的可施加正压力的剪切试验仪,测试了2种水环境(无水和浸水)和3个正压力(0.3,0.5,0.7MPa)下沥青混凝土及其与水泥混凝土板层间抗剪强度,并进行了2种水环境、2个正压力(0.5,0.7 MPa)和4个剪切应力比(0.4,0.5,0.6,0.7)下沥青混凝土及其层间剪切疲劳试验。在此基础上,结合复合式路面结构的三维有限元计算,对比分析了不同水环境、垂直和水平荷载下沥青铺装层及其层间剪切疲劳寿命。研究结果表明:沥青混凝土和层间剪切疲劳寿命均与剪切应力比具有良好的双对数线性关系,剪切疲劳特性参数与材料特性、环境因素、交通荷载和沥青铺装结构等有关;层间抗剪强度和剪切疲劳寿命均低于沥青铺装材料的抗剪强度和剪切疲劳寿命,层间剪切破坏沿混凝土板表面发生;浸水导致层间剪切疲劳寿命降低85%以上,水平力和超压作用缩短层间剪切疲劳寿命45%以上,浸水比交通荷载的影响更大。
In order to make up for the insufficiency of design method of shear fatigue life between asphalt pavement of cement concrete slab, the asphalt concrete and its shear strength and shear fatigue test with cement concrete slab under different water environment and positive pressure, The influence of water and overloading on the shear fatigue life of asphalt concrete pavement between concrete pavement and asphalt pavement was discussed. Two kinds of water environment (no water and water immersion) and three positive pressure (0.3,0.5,0.7MPa) asphalt concrete and its interface with the cement concrete slab were tested by self-developed shear tester capable of applying positive pressure. Shear strength of asphalt concrete and interlaminar shear fatigue tests under two kinds of water environment, two positive pressure (0.5,0.7 MPa) and four shear stress ratio (0.4,0.5,0.6,0.7). On this basis, combined with the three-dimensional finite element calculation of composite pavement structure, the shear fatigue life of asphalt pavement and its layers under different water environment, vertical and horizontal loads are comparatively analyzed. The results show that both the shear fatigue life of asphalt concrete and interlayer have a good double logarithmic linear relationship with shear stress ratio, and the parameters of shear fatigue are related to material properties, environmental factors, traffic load and asphalt pavement structure. The interlaminar shear strength and shear fatigue life are both lower than the shear strength and shear fatigue life of asphalt pavement materials. The interlaminar shear failure occurs along the surface of concrete slab. The immersion water reduces the interlaminar shear fatigue life by more than 85% , Horizontal force and overpressure shortens the interlaminar shear fatigue life by more than 45%, and flooding has more influence than the traffic load.