In the construction of artificial slopes in landslide areas, soft-ground areas, and urban areas, it is important to place multiple surface and underground sensors in response to geology and displacement characteristics of the area and to identify the changes in the area over time. Accordingly, we have developed a three-dimensional information and communication technology (3D-ICT) system that shows various measurement data in real time on a website and determines the overall ground stability using a newly developed evaluation technique. This report outlines the system, the gives examples of application to open-cut excavation and tunnel construction, and presents details of the system using construction information modeling/management concepts.
The deformation and failure of slopes are important considerations in excavation under difficult ground conditions such as in areas with soft ground, in areas prone to landslides, and in urban areas with neighboring constructions. Therefore, to evaluate the stability of rock slopes and ensure the safety of a construction, many sensors are typically placed to monitor the condition of the ground as the construction progresses.
However, it is difficult to integrate data processing with a variety of measuring instruments that are supplied by different manufacturers and placed on the ground and underground. Furthermore, quick and comprehensive processing of measurement data is absolutely imperative for understanding the situation when slope deformation or failure occurs as a result of rain or an earthquake, but a problem with conventional systems is that they require a long time to comprehensively evaluate stability when data from different measuring instruments must be processed separately. To solve this problem, we have developed a slope-measuring three-dimensional information and communication technology (3D-ICT) system, called the Hazama Ando Automatic Monitoring System (HAMONIS), that can handle various measuring instruments and that integrates the measurement data and provide them over the Internet in real time (see Fig. 1).
This system was adopted at construction sites where there were problems with the stability of excavation slopes or with displacement in areas with shallow soil cover due to excavation for the tunnel construction. The system contributed to the quality and safety of the site.
Various tests are now carried out in such cases by using construction information modeling/management (CIM) as shown in Fig. 2. Specifically, the geological conditions assumed in the feasibility and design stages are put into a 3D model, and the existence of unstable ground is examined in detail, so that such ground is addressed in the excavation plan or countermeasure designs, depending on the situation. In addition, in our approach, observation results on the geological structure on the tunnel face and excavation slope are input into the model during the construction stage so that the work results can be efficiently summarized in order to examine any differences between the preliminary study results and the actual situation and to discuss any necessary changes in the construction plan or design.