The invention discloses a transformation structure and method of a dam foundation draining hole of a dam of a hydroelectric
station. The transformation method of the dam foundation draining hole of the dam of the hydroelectric
station comprises the following steps that (1) the foundation
uplift pressure at the position of the dam foundation draining hole is measured; (2) when the foundation upliftpressure is larger than a design value, a groove is carved in original concrete in the axial direction of an original horizontal draining
pipe, and the original horizontal draining
pipe is disassembled; (3) backfilling is conducted on the carved groove with
cement mortar, plastering is conducted on the two sides and the bottom of the groove with
cement mortar, and a
drainage ditch is formed; (4)hole bottom cleaning treatment is conducted on the original draining hole; (5) an auxiliary draining hole is additionally arranged at the position where the foundation
uplift pressure is larger than adesigned value, a t-
branch pipe is installed at an opening of the upper end of the auxiliary draining hole, an end cap is arranged at an upper end opening of the t-
branch pipe, and the other end opening of the t-
branch pipe is connected with the
drainage ditch through a pipeline. According to the transformation structure and method of the dam foundation draining hole of the dam of the hydroelectric
station, an existing dam foundation draining hole is transformed, especially the auxiliary draining hole is additionally arranged beside a blocked draining hole, so that the blockage problem of vadose water is effectively solved, the dam foundation
uplift pressure is reduced, and stable operation and safety of the dam are guaranteed.