This paper establishes a composite material damage analysis strategy that retains the hygrothermal state to investigate the damage behavior and mechanical performance characteristics of composite materials in hygrothermal environments. Initially, mass diffusion and heat conduction are equivalently considered, and a hygrothermal state predefined model is developed using a combination of sequential and fully coupled approaches. Then the hygrothermal stress field is extracted as the initial state of the compression process, and a compression progressive damage analysis is conducted using the VUMAT subroutine. Additionally, the accelerated hygrothermal aging experiments are conducted to investigate moisture absorption behavior and moisture diffusion coefficients. Then the quasi-static compression tests are carried out on the specimens before and after aging, with failure processes recorded using Digital Image Correlation (DIC). Experimental and simulation results reveal that hygrothermal conditions lead to matrix cracking and debonding from the fiber surface, generating an uneven stress field internally. This results in earlier occurrence and increased severity of delamination during the compression process. The dominant failure modes include wedge splitting and longitudinal cracking. The compressive strength, failure strain, and elastic modulus of the specimens decrease after aging. The analysis strategy developed in this paper effectively reflects the hygrothermal state during compression, aligning more closely with the actual physical processes.

本文建立了保留湿热状态的复合材料损伤分析策略，以研究湿热环境下复合材料的损伤行为和力学性能特征。最初，等效地考虑质量扩散和热传导，并使用顺序和完全耦合方法的组合开发了湿热状态预定义模型。然后提取湿热应力场作为压缩过程的初始状态，并利用VUMAT子程序进行压缩渐进损伤分析。此外，还进行了加速湿热老化实验来研究吸湿行为和水分扩散系数。然后对老化前后的试件进行准静态压缩试验，并使用数字图像相关（DIC）记录失效过程。实验和模拟结果表明，湿热条件导致基体破裂并从纤维表面脱粘，从而在内部产生不均匀的应力场。这导致压缩过程中分层的早期发生和严重程度的增加。主要失效模式包括楔裂和纵向裂纹。老化后试样的抗压强度、失效应变和弹性模量下降。本文提出的分析策略有效地反映了压缩过程中的湿热状态，更符合实际的物理过程。