This work proposes an alternative approach for the nonlinear analysis of 2D, thin-walled lattice structures. The method makes use of the well-established Carrera Unified Formulation (CUF) for the implementation of high order 1D finite elements, which lay along the thickness direction. In this manner, the accuracy of the mathematical model does not depend on the finite element discretization and can be tuned by increasing the theory approximation order. In fact, the governing equations are invariant of the order of the structural model in CUF. Another advantage is that complex curved geometries can be considered with ease and without altering the nonlinear strain–displacement relations. After a preliminary assessment, attention is focussed on the nonlinear equilibrium analyses of U-shaped 2D lattice structures both in traction and compression. Also, a sensitivity analysis against the effect of various geometrical nonlinear terms is conducted. The results demonstrate the accuracy of the present method, as well as its computationally efficiency, giving confidence for future research in this direction.

这项工作为二维薄壁晶格结构的非线性分析提出了另一种方法。该方法利用完善的Carrera统一公式（CUF）来实现沿厚度方向放置的高阶一维有限元。以这种方式，数学模型的精度不取决于有限元离散化，而是可以通过增加理论逼近阶数来进行调整。实际上，控制方程是CUF中结构模型顺序的不变性。另一个优点是可以轻松地考虑复杂的弯曲几何形状，而无需更改非线性应变-位移关系。经过初步评估后，注意力集中在牵引和压缩方面的U形2D晶格结构的非线性平衡分析上。也，针对各种几何非线性项的影响进行了敏感性分析。结果证明了本方法的准确性及其计算效率，为该方向的未来研究提供了信心。