土石坝沥青混凝土心墙材料参数对其工作性状的影响

Effects of Material Parameters of Asphalt Concrete Core Wall Dam on the Working Conditions of Core Wall

在沥青混凝土心墙坝的设计中,应将试验和设计紧密相连,综合考虑各参数的影响,利用计算来指导试验,调整优化配合比设计,使大坝达到较佳的工作状态。针对新疆某沥青混凝土心墙坝,对坝体的各部分材料进行了三轴试验,得到邓肯-张E-u模型参数,并对沥青混凝土心墙坝进行三维非线性有限元分析。根据温控参数折减法,研究了邓肯-张E-u模型参数对沥青混凝土心墙的最大水平、竖向位移及大、小主应力的影响。结果表明:黏聚力c、内摩擦角φ、参数k和G对心墙的最大水平、竖向位移及大主应力的影响较大,但对小主应力的影响不明显。其他参数对最大位移和大、小主应力的影响则相对较小。研究结果可为沥青混凝土配合比设计优化和数值计算提供依据和参考。

During the design of asphalt concrete core wall dam, the test and design were closely linked as the calculation consider- ing all parameters was used to guide the test and then to adjust and optimize the mix ratio design, therefore achieving the better working conditions for the dam. In this study, an asphalt concrete core wall dam in Xinjiang was used as the example. Each part of the dam was examined by the triaxial tests to obtain the parameters for the Duncan-Chang E--u model. Moreover, the As- phalt concrete core wall dam was analyzed using the three-dimensional non-linear finite element method. Based on the tempera- ture control parameters reduction method, the effects of Duncan-Chang E--u model parameters on the maximum horizontal and vertical displacements,and the major and minor principal stresses of the asphalt concrete core wall were investigated. The re- sults showed that the cohesion c, internal friction Angle q~, and the parameters k and G have larger impacts on the maximum horizontal and vertical displacements and the major principal stress of core wall, but insignificant impacts on the minor principal stress. Additionally, other parameters had slight impacts on the maximum displacement, and the major and minor principal stres- ses. The results can provide the basis and reference for the optimization design and numerical calculation of mix ratio between asphalt and concrete.