“…Belytschko et al proposed the popular element free Galerkin method (EFGM), in which the EFGM error estimation is given to make in-depth study on the numerical integration scheme, thereby laying the mathematical foundation of the method (Belytschko et al, 1994;Ventura et al, 2002). The meshless method is mainly suitable for solving deformation analysis of jointed rock mass (Hajiazizi and Graili, 2018), fluid-structure interactions (Hu et al, 2019), fracture analysis (Memari and Mohebalizadeh, 2019), diffusion problem (Tayefi et al, 2018) and large deformation problem (Lin et al, 2014), etc. This method has been widely used in multiple fields (Wang, 2012;Belytschko et al, 1995;Fouaidi et al, 2019;Li and Belytschko, 2001).…”