Abstract
For level 2 design earthquakes, shear properties of the reinforced concrete sidewall of the excavation portion in the U-type cross section of the existing tunnel is studied. The cross-sectional forces are calculated by dynamic response analysis considering material non-linearity. Calculation results show the destructive mode at side wall is shear type, and shear reinforcement is required to increase shear strength of the wall
However, there is no appropriate counter measure about how to reinforce these structures. Therefore we propose the new reinforcement method by SHEAR STEEL RODS EMBEDDING. Holes are drilled at the sidewall, the steel rods are put in and embed with fixate. Static monotolic loading tests and reversal cyclic loading tests verify the efficiency of the embed steel rods for shear reinforcement.
