Internal spill boundary processing method in seepage value calculation

The invention discloses an internal spill boundary processing method in seepage value calculation. The internal spill boundary processing method is capable of automatically judging a recharge relation between seepage from the internal spill boundary and a node needing recharge on the downstream side or the lower portion of the spill boundary, thereby realizing the continuity of the seepage and improving the accuracy of seepage value calculation. The internal spill boundary processing method comprises the following steps: (1) judging the flow form of an internal spill boundary slope according to the form of the slope: if the slope is a dip slope or a vertical slope, the flow form is downslope flow, and if the slope is a reverse slope, the flow form is vertical dripping; and (2) determining the recharge relation according to the flow form: for the downslope flow, the flow of the internal spill boundary is recharged to the lower node of the lower seepage face of the slope, and for the vertical dripping, the flow of the internal spill boundary is recharged to the node of the opposite side of the internal spill boundary.