In this study, It was found that replacing a large amount of mineral admixture, we satisfied the target, compressive strength of 30, 50MPa and manufactured lightweight concrete reducing CO2 emissions up to 42.1～52.8% comparing normal concrete

Important factor of underground structures utilizing precast and rigid wall is joints and connections of wall-to-wall and wall-to-slab for safety performance and durability of underground constructions. In this study, conducting research on the structural safety of the connection as a future laboratory experiments and connection method for the verification of the details of the construction method is expected to proceed research.

Recently, modular technologies have been developed in nuclear power plant structures and bridge structures. In addition, they can be utilized in the underground structure of near surface transit system. In this study, the research and development plan of the modular slab structure and construction technology for near surface transit system described.