In Japan, with a goal of "reduction of total cost on construction by sharing and utilizing 3-dimensional model in construction industry", introduction of CIM (Construction Information Modeling) to construction field proceeds at a rapid pace. Mikusa Tunnel is a road tunnel of 2,380m length in Kinki Expressway Kisei-Route. In Mikusa Tunnel, CIM model building in tunnel construction has been addressed first in Japan. In this paper, specific case examples of efforts during CIM model building will be discussed.
Until recently, tunnel excavation has been executed by predicting the geological conditions ahead of face based on the 2-dimensional drawing such as geological plan and information obtained from face observation and measurement results. In consequence, tunnel progress and quality are highly dependent on the skill and experience of site engineers. Therefore, stereoscopic images such as geological formation and tunnel alignment were difficult to share between persons involved in the tunnel construction, and some cases of stand by and rework took its rise. Furthermore, since information obtained during construction was not sufficiently carried on into maintenance service, data mining of the information on construction and quality management was not easy in case of trouble after services commencement. Consequently, CIM has been innovated to improve data sharing method and finally to make tunnel construction more efficient and sophisticated.
As specific actions, 3-dimensional model developed based on geological formation in design stage was integrated by incorporating the information such as face observation, measurement results, and adopted support pattern obtained during construction stage. Uniform management using the integrated model enabled the information visualization, the enhancement of cooperation between owner and contractor due to data sharing, and the efficient tunnel construction. Furthermore, the uniform management enables the deterioration prediction of the completed tunnel based on geological and water inflow conditions during construction, and will contribute well-planned maintenance service. From now on, crack data on concrete lining is incorporated to the integrated model, and long-term maintenance model is planned to build.
