The Present State and tasks of Observational Construction System

Recently, Observational Construction System (OCS) is thought to be one of the most important technologies in the construction field. And it is applied to many civil construction sites these days. Especially in the construction site, such as the braced excavation using an earth-retaining wall with a depth of 15 meters or the tunnel project by NATM could not have been complete it without OCS. And it is used in new construction site s, such as the sites of soft ground or the sites of underground excavation, and so on.In these 20 years OCS was dramatically developed. That is mainly because of the great progress of computer hardware, software, information-technology, communicationtechnology, and so on. Such kind of technologies made it possible to use OCS easily and effectively. However, there are several tasks that have not been solved yet. This paper first reported how OCS is applied actually and evaluated some basic technologies used in OCS.Secondly represent some tasks and the solutions which OCS have on its own, and finally indicate desirable future of OCS.