颗粒之间的毛细作用是分析湿颗粒体系力学特性的一个重要方面。考虑两球形颗粒与粒间弯液面的相互作用，采用打靶法求解得到了粒间气-液-固交界面的几何形状与基质吸力关系的精确解答，并与环形近似方法和数据拟合方法得到的粒间作用力进行了比较，分析了两种简化方法的精确度。在此基础上，分析了不同粒间间距、液-固接触角以及基质吸力时，两球形颗粒间由毛细作用引起的吸应力特征曲线。分析结果表明，当液体体积较小时，拟合方法得到的结果更好，而当液体体积较大时，采用环形近似得到的结果要比拟合方法更接近精确解，为非饱和土中吸力的认识以及非饱和土力学微观分析提供了一定的理论指导。

The capillary interaction among particles is an important aspect of analyzing the mechanical properties of wet granules. By considering the interaction between two spherical particles and the inter-particle meniscus, exact solutions for geometry and matric suction of the interface of gas-liquid-solid are deduced by shooting method. The results by the proposed method are compared with the inter-particle forces obtained by the annular approximation method and the data fitting method to evaluate the accuracy of the two simplified methods. The characteristic curves of the suction stress caused by the capillary action between the two spherical particles are analyzed for different inter-particle spacings, different liquid-solid contact angles and different matrix suctions. The results obtained by the fitting method are better for the smaller volume of the liquid, and the result by the circular approximation is closer to the exact solution than that by fitting method for larger liquid volume. This study provides some theoretical guidance for understanding the suction in unsaturated soils and microscopic analysis of unsaturated soil mechanics.