A Basic study on geological risk reduction in Japan public works

In recent years, as the finance of the national and local governments becomes severe in Japan. The government construction investment has been decreasing, and now it is reduced by 48.9 percent from its peak. People’s cost consciousness is also rising due to cut in the construction investment. The public works project in Japan is under severe conditions due to the budgetary cutback. Responding to this situational change, the government has started implementing the cost structural reform of public works” used for the whole government in 2003. This reform describes reconsideration of all processes of the public works project from cost viewpoints. However, “the viewpoints from the geological feature” are not specifically described. Geological conditions influence effectiveness and/or efficiency at any stage of life cycles of public works, conception, design, construction, and maintenance. In this study, thus, setting "reduction of the geological risk in public works" as the ultimate goal, an attempt is made to study a possibility of lowering the geological risk by introducing geological engineering advisor and concept of GBR (Geotechnical Baseline Report), developed and applied in a large-scaled underground construction project in the U.S. Here, geological risk is defined as a possibility of cost increase and/or project delay caused by poor or insufficient treatment of geological conditions. It is observed that the public client and the contractor have her/his own worry about payment associated with design document change: “Paying too much” and “Paid enough?,” respectively. It is concluded that introduction of geological engineering advisor is expected to reduce the public client’s worry and that concept of GBR is expected to reduce the contractor’s worry