摘要
土工格室加筋层设计应考虑其各向异性的力学性能,利用试验方法测得所有各向异性常数较为困难。通过对土工格室加筋层代表体积单元进行多尺度分析和加筋路堤实体建模仿真,得到所需参数。计算结果表明:采用渐进均匀化方法能够计算三维土工格室加筋层的等效弹性常数,并推导出杨氏模量、泊松比和剪切模量;土工格室的铺设方式对加筋层水平方向的杨氏模量、泊松比和剪切模量有显著影响;加筋层水平方向的泊松比分量为负值,表明加筋层在该平面内有负泊松比特性;土工格室在路基中采用45°铺设方式比采用0°铺设方式可减少路基水平方向的变形值,但对竖向沉降几乎没有影响。
Anisotropy mechanical properties should be concerned as designing the geocell-reinforcement of embankment, and measuring all anisotropic constants is difficult by experimental method. The required parameters were obtained by the multi-scale analysis of representative volume elements(RVE) of the geocell-reinforcement and simulation of the reinforced embankment. The conclusions are summarized as follows:The equivalent elastic constants of the 3D geocell-reinforcement could be computed by AHM, and Young's modulus, Poisson's ratio and shear modulus are deduced by using these; Laying method of geocell affected markedly the mechanical parameters such as Young's modulus, Poisson's ratio and shear modulus of the geocell-reinforcement; The Poisson's ratio components in horizontal direction of the geocell-reinforcement are negative, which indicates that the geocell-reinforcement has a negative Poisson's ratio characteristic in horizontal direction; Comparing with adopting the 0° laying method of geocell, adopting the 45° laying method of geocell could reduce horizontal deformation values of embankment, but has little effect on the vertical settlement of embankment.
引文
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