Abstract: A laser positioner is located at a survey base point for projecting a geodetic design pattern depicting design working points onto a working face remote from the base point by use of a laser pattern projector, upon surveying an object route by use of a laser surveying unit. In tunneling operations for example, the design pattern is formed on the working face, so that boring of the holes for charging explosives in the working face can be performed without paint-marking on the working face.

Abstract: In laser surveying system has a laser measuring unit which is operable independently of a laser projector, a laser spot pattern is first determined by using the laser measuring unit and projected onto the working face of an object structure by driving the laser projector. While marking the working face with the laser spot pattern formed by the laser projector to execute the desired construction work, the laser measuring unit is turned toward a different measuring object so as to independently make other measurements. Thus, point marking and measurement on different objects can be rationally effected at one time.

Abstract: A tunnel driving method using a drill carriage provided with plural number of drill booms having drifters. According to a preferred embodiment, while the drill carriage is placed before a bench, the charging cages are moved to mark blasting holes and rock bolt holes for an upper portion. While the drill carriages are moved backward with a predetermined length, the charging cages are moved to insert the rock bolts for the upper portion. Simultaneously, the charging cages are operated in a lower portion to bore blasting holes for the lower portion. Then, the charging cages are operated to charge the blasting holes for the upper portion and the lower portion with dynamite for blasting so that the facing is broken and a new facing is formed. Subsequently, after first and second operation of concrete shooting, the above continuous operation is performed repeatedly.