基于三维离散元法的钢桥面铺装层间剪切模拟

Shear test simulation of steel deck pavement based on threedimension discrete element method

为了研究钢桥面铺装层间剪切破坏行为,采用离散元方法,建立钢桥面铺装复合结构试件的三维数值模型;通过DSR试验,获得沥青砂浆30℃和60℃条件下的Burgers模型参数,并计算得到沥青砂浆的细观参数作为离散元模型的输入参数;通过数值模拟分析了30℃和60℃条件下的钢桥面铺装层间剪切行为,与室内剪切试验结果进行对比,并且分析钢桥面铺装层间粘结失效情况和裂缝发展情况。研究结果表明,离散元数值模型能够较好地模拟铺装体系复合结构层间剪切行为;在虚拟剪切过程中,集料单元与钢板单元之间的粘结最先开始失效,随着剪切位移的逐渐增大,裂缝沿着钢板和沥青铺装层界面不断发展,最终贯穿整个界面。粘结失效集中在钢板与沥青铺装层界面之间,沥青铺装层内部单元之间没有粘结失效。

In order to study the steel bridge pavement shear failure behavior,the 3D discrete element model of steel deck pavement composite structure was established by using discrete element method.The meso parameters of asphalt mortar under 30℃and 60℃were calculated by using the Burgers model parameters obtained by DSR test.The interlaminar shear behavior of steel deck pavement under 30℃and 60℃was simulated and compared with the results of laboratory shear tests.The bond failure between the steel deck pavement and the crack development is analyzed.The results show that the interlaminar shear behavior is simulated well by using the discrete element method.The cracks appear when the bonding between the aggregate unit and the steel plate unit begins tofail,and develop gradually along the interlayer with increasing shear displacement,and finally run through the interface between the steel plate and the pavement.The integrity of the pavement is basically maintained because the bonding failure mainly lies between the steel plate and the pavement layer and there is no bonding failure between the units in the pavement.