The HTLP method was developed aiming at the economical dam foundation grouting. This new method is characteristic in using high-thickness cement mixes and injection by comparatively low pressure. We applied it in consolidation grouting of Ueno Dam under construction currently by Tokyo Electric Power Company in order to confirm the effectiveness of this method. This is the first case that we applied HTLP method to real execution of a dam. As a result, it was confirmed that shortening effect of injection time and contribution to reduction of construction cost were remarkable. In addition, we applied high-thickness cement mixes (It is not HTLP method itself exactly) to execution of curtain grouting of Ueno Dam. As a result, it was also confirmed that use of high-thickness cement mixes was effective for promotion of efficiency of curtain grouting.

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Dam-toe-footing type training waterway is commonly employed for gate-less gravity concrete dams, and hydraulic design of this training waterway is usually obtained through 3D hydraulic model test. Since the spillway of this type has wide overflow crest with small water-head, depth in a model becomes very thin. This brings the application problem of similarity low of model flow, and deflector is installed on the top of wall for preventing overflow water. Deflector is, however, not suitable for construction, and then appropriate treatment method for measured water surface profile is required. This paper shows the effects of model scale in measured water surface along training wall. Results are obtained by the experiments using some similar and different size models. Errors in measured values by gauge, usually used as a measuring tool in model tests, are also discussed by comparing with the values of electrical measuring instrument.

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Consistency of RCD is measured with VC value, in general. This paper discusses the nature of VC value of RCD and effect of VC value on compacting RCD. As the result of compaction tests of RCD, it is found that VC value is largely affected by the volume of paste in RCD, and that compaction density of RCD is approximated by the function of the normalized compaction time which is defined as real compaction time divided by VC value.

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The volcano Mt. Unzen-Fugendake became active in November in 1990 after being dormant for 198 years. The resulting pyroclastic flows, rock avalanches, ash showers and mudslides caused devastation in the local area, affecting residents and property alike. In 1994 work began on disaster recovery projects and schemes to limit the impact of future volcanic activity. This work required the use of remotely-controlled, full-sized construction machine due to concerns about workers'safety. It was made possible by combination of remote control and image transmission technologies. Although early survey work at Mt. Unzen-Fugendake had to be done using human workers with an enhanced evacuation system, it was clear that this work should also be done by unmanned systems and over the course of this project, a remote surveying system and a system for displaying execution management lines from remote monitors was developed. The remote surveying system was tested and its applicability to real-world projects was verified. From the results obtained, it became apparent that the technology could be applied to other civil engineering works including dam construction. In this paper, in order to help other developments in civil engineering fields, thed etails of the developed systems, and the applicability of these systems in the No.2 Mizunashi-river check dam project ect are discussed.

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