ABSTRACT
The increase of population and traffic in urban areas has urged civil engineers to develop underground structures, which also cause various problems related to the construction process, maintenance and water leakage. Therefore, the safer and more suitable for Korean geotechnical conditions methods of underground construction have been required. In connection with the above problems and requirement, N.T.R (New Tubular Roof) method was proposed . In this research, the overall features, construction procedures were overviewed and applicable capacity of N.T.R method were inspected, furthermore, practical measurement data of a tunnel using N.T.R method were obtained and compared to the result of numerical analysis.
