Most underground retaining walls are constructed from massive concrete, which causes thermal cracks to appear in wall due to heat generation. Crack control joints are generally used as countermeasures to prevent cracking, but they necessitate section loss rates of approximately 20% -30% of a wall’s diameter. The authors developed a new crack-control joint, installed only in the surface region where tensile stress is caused by the temperature differential between the inner and outer layers of massive concrete. Temperature stress analysis confirmed that tensile stress was concentrated in the experimental crack-control joint. In field application to walls at a construction site, cracking was not observed anywhere other than the installation location of the experimental crack-control joint.
