提出了一种用于热弹性多构型梯度点阵结构设计的拓扑优化方法。假设结构由各种空间变化的点阵子结构组成。每个点阵子结构考虑2个设计变量，一个准离散变量决定其空间拓扑布局，另一个连续密度变量决定其材料用量。对于预定义几何拓扑的点阵子结构，通过改变其特征尺寸，获取一系列定构型、变密度的点阵子结构样本，并进行静态凝聚以降低自由度数目，依此建立相应的数据驱动插值模型，显式地关联点阵密度变量与其热弹性等效本构行为。进一步地，为实现多构型点阵的混杂布局设计，构建了准离散点阵选型变量的多材料插值模型。数值算例结果表明，设计方法能够利用梯度点阵材料平衡温度载荷作用下引起的机械变形，进而有效地提升结构的热-机械耦合承载能力。此外，由于基于子结构法进行梯度点阵结构建模，整体结构与点阵子结构的几何构型和热弹性性能均是耦合的。相较于基于均匀化理论的设计方法，本文设计方案无需额外的几何后处理，可有效避免设计与制造的性能偏差。

This paper presents a topology optimization method for the design of thermoelastic multi-configuration gradient lattice structures. Specifically， the structure is assumed to consist of several spatially varying lattice substructures. For each substructure， two design variables are considered： a quasi-discrete variable， which determines its spatial topological layout； a continuous density variable， which determines its material usage. For the lattice substructures with predefined geometric topology， a series of samples of lattice substructures with fixed configuration and variable density are obtained by varying their feature sizes， and static condensation of the substructures is performed to reduce the number of degrees of freedom. On this basis， the corresponding data-driven interpolation model is built to explicitly correlate the density variable with the thermoelastic equivalent constitutive behavior of the lattice substructure. Furthermore， to realize the hybrid layout design of multi-configuration lattice substructures， a multi-material interpolation model for quasi-discrete lattice selection variables is constructed. The numerical example results show that the design method is able to utilize the gradient lattice structures to balance the mechanical deformation caused by temperature loading， which in turn effectively enhances the thermo-mechanical load carrying capacity of the structure. Moreover， since the gradient lattice structure is modeled based on the substructure method， the geometrical configuration and thermoelastic properties of the whole structure and the lattice structures are coupled. Compared with the design method based on the homogenization theory， the design scheme proposed in this paper does not require additional geometric post-processing， effectively avoiding the performance deviation between design and fabrication.