An improved version of the node-based smoothed point interpolation methods (NSPIMs) is proposed for coupled hydro-mechanical problems of geotechnical engineering. In the improved NSPIMs (I-NSPIMs), the polygonal nodal smoothing domains are estimated with area-equivalent circular domains. The smoothed strains over the circular nodal smoothing domains are then assumed to be linear, in contrast to the constant smoothed strain adopted in the original NSPIMs. The efficiency of the proposed method is investigated through five practical examples, all showing clear superiority of I-NSPIMs over the original formulation of NSPIMs in small deformation problems of geomechanics.

针对岩土工程的耦合水力机械问题，提出了基于节点的平滑点插值方法 (NSPIM) 的改进版本。在改进的 NSPIMs (I-NSPIMs) 中，多边形节点平滑域是用面积等效的圆形域估计的。然后假设圆形节点平滑域上的平滑应变是线性的，这与原始 NSPIM 中采用的恒定平滑应变相反。通过五个实际例子研究了所提出方法的效率，所有例子都表明 I-NSPIMs 在地质力学小变形问题中明显优于 NSPIMs 的原始公式。