With the conventional discharge conduit design, conduit design has been done without considering the concrete surrounding the conduit and the dam body design has been done without considering the conduit, respectively. However, in reality the discharge conduit is constrained by surrounding concrete, with both sharing the load (by acting together). Also, a considerable ratio of the tensile force produced around the conduit is resisted by the concrete itself.

Based on the above, by supplementing the design conditions with [1] consideration of the fact that the discharge conduit and the surrounding concrete are acting together and [2] prediction of strength considering the tension softening properties limited to the concrete around the conduit, concrete placement works of structurally important parts of the dam was improved and the discharge conduit stiffening materials and structural reinforcing bars around the discharge conduit were rationalized.