A FAST AND ACCURATE ANALYSIS OF GROUNDING RESISTANCE OF A DRIVEN RODBED IN A 2-LAYER SOIL

A moment method of the Galerkin (variational) approach is applied to a nalyze the grounding resistances of driven rodbed of various configura tions. Using this approach the resistance of a rodbed of N rods in two -layer soil requires only a matrix size of 2NX2N (two segments for eac h rod). The error in the calculated resistance is less than 4% compare d to the resistance calculated by point matching moment method of larg e number of segmentation for each rod. The efficiency due to a snell m atrix with high accuracy allows an extensive parametric analysis of th e rodbed. The study shows that a precise placement of the rods is not necessary to maintain a given resistance.