Geomechatronics is a technical field in which the Geotechniques is fused with the Mechatronics that is the technical field to promote the automatic control of machines by using the electronics. In the field of Geomechatronics, the machinery, which treats the geomechanical materials such as soils and rocks, automatically evaluates the properties and conditions of the ground and determines the optimum controlling method of itself for the ground with the base of the interaction between the machine and ground. We introduce the elemental techniques required for geomechatronics and some researches for practical use in this field, and then express the progressing view of this research and technical field.

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At the port of Fushiki Toyama a quay with 14m depth of water was constructed. This quay was designed on the steel pipe piles installed by water jet vibratory (JV) technique. The static load test performed on the JV pile showed the shortage of the bearing capacity. To increase the bearing capacity new technique using cement milk in place of water (CJV method) was developed to use for improving the soil. For the exited piles where JV method was used, cement grouting method was carried out. The results of the static load test and dynamic load test showed that the designed bearing capacity was achieved.

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35 Years have passed since reinforced concrete rigid frame viaducts of the Tokaido Shinkansen, where deformed bars were used as main reinforcements for the first time, were constructed in 1964. For maintenance and estimation on serviceability of these structures in the future, it is necessary to obtain capacity and fatigue strength of their members. Longitudinal beam members of the Shinagawa bridges, which became out of service with construction of the Shinagawa station, were cut and brought out. Then material test, fatigue test and capacity test using these specimens were completed for investigation on fatigue strength and capacity of those members. As a result, it was found that safety of the structures in terms of member capacity and fatigue strength was confirmed for additional 20 years.

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In this study, using Winklerian model, five different companies made attempts to predict the performance of braced wall excavation with floating type earth retaining wall in a model site For one location, three different type of predictions were carried out without any observed data, Type A, with observed data until the second stage excavation, Type B, and with all observed date, Type C. Type D prediction was also done for the other location using the input parameters derived in the Type C prediction. By comparing the results of these predictions with the observation, discussed were effects of input soil parameters on the prediction and validity of various conditions assumed in the current design methods using Winklerian model.

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The connection between a flange of a cross beam and a web of a main girder is welded by full penetration, regardless of the magnitude of transmitting stress at a cross beam. However, the magnitude of stress depends on position, so there are some cases that the full penetrated welding is not necessary. In this paper, an application of partial penetrated welding to the connection has been discussed in order to improve the environment of the working area and reduce the fabrication cost. For this purpose, the stress on the flange of cross beam has been examined on the basis of usual design, welding procedure tests and tensile coupon tests were carried out, and fatigue strength of the connection with partial penetration welding has been discussed.

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The port structures in KOBE were heavily damaged after the Hanshin-Awaji Earthquake in 1995. This paper presents the damage investigation of the existing piers in KOBE Port such as dolphins and detached piers. Observed damages of the steel piles in KOBE Port are mainly caused by the lateral movement of surrounding soils and retaining walls behind the structure. The static elasto-plastic analysis is performed to ensure the damage mode. It is understood that the static analysis cannot proof the permanent deformation after the quake and it is necessary to perform the nonlinear dynamic analysis to get the proper deformation. The under-water shaking table tests are carried out to be compared with the observed damage and the numerical analysis.

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A blasting system consisting of a combination of non-electric detonators and ANFO explosives has been in use recently for tunnel blasting in Japan. However the system has a few problems, such as additional requirements to the system and air pollution in a tunnel by blast fume.
A blasting method using bulk emulsion explosives which is developed overseas presents a solution to the above such problems, but the introduction of the method is difficult under the regulations in Japan. Authors have developed a bulk emulsion blasting system that complies with the regulations, and verified and studied its work efficiency and feasibility of blasting performance.

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There are various forms for the density of buildings in the cities. The density of buildings should be analyzed with the qualitative distribution of buildings for regional comparison. The objective of this study is to develop the analysis method on the building density assuming the utilization of high-resolution satellite data. The analysis with the calculation of entropy was applied for 320 building-map data considered the distribution types of buildings, the spatial resolution of the data, the requirements of entropy calculation, and the locational directions of buildings. It was suggested that the categorization of the building-distribution types might be possible with the calculated entropy and areal ratio of buildings.

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In this paper, the methodology for detecting critical properties using rough set theory is applied to the rainfall data in Yamaguchi prefecture, for the purpose of analyzing the relationship between rainfall and slope failures. It is shown that there exist two types of slope failures, “immediate failures” and “late failures, ” in andesite slopes. On the other hand, “late failures” and “accidental failures” could happen in granite slopes. The result of χ² test shows that there is no significant correlation between geological properties of slopes and the type of slope failures, in the data which can be obtained.

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It is one of the most important problems in tunneling jobs to improve its working environment. Particularly in muck haulage, dump trucks have been used for mucking out, and this causes an inferior work environment in tunnels due to exhaust gas and dust produced by dump tracks. The authors developed the Continuous Conveyor System for the removal of spoil excavated by drilling+blasting method instead of dump thick transportation Generally, excavation, concrete lining and invert work are concurrently executed in tunnel construction. The difficulty was to complete the conveyor system that would not disturb another works. This paper describes the arrangement and support measures of belt conveyor that were the most important point in this development and for applying this system to muck haulage in tunnels.

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This paper presents a methodology to design an optimum maintenance system that considers the problems in both space and time scales. An objective-function is formulated to evaluate the deterioration of existing road pavements. As an effective tool, the Hopfield neural network is used to perform the optimization procedure. Through the numerical simulation using the proposed optimum modeling, the concept of the optimum maintenance section and the relationship between maintenance interval and maintenance method are discussed in detail.

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Forecasting of structure behavior of the underpinning is carried out generally using simple settlement calculation for pile foundations. In actuality, there is not good congruence between forecast values and actual measured values. This cause originates in the interaction between behaviors of existing piles and those of new ones through the ground being disregarded. This paper evaluates the interaction of the existing and new piles, proposing a complex spring model that can explain the behaviors during the underpinning work. It also clarifies the suitability of this structural model by making comparisons of site measurement values.

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For prevention of earthquake disaster at a site, it is needed to investigate dynamic physical properties of subsurface layers and ground-motion characteristics at that site. Thereupon, first this study makes characteristics of S-wave velocity, P-wave velocity, and Poisson's ratio clear, based on PS logging for erratic subsoil on subsurface layers. Second this study proposes an empirical equation of S-wave velocity for subsurface layers in Okinawa. Furthermore, from comparison with other typical formulas, the availability of the proposed formula is shown.

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Principle of gravel compaction pile method is to increase the density of loose sandy ground and to prevent damage of structure due to liquefaction using the gravel piles, which will immediately dissipate the excess water pressure occurred in the sandy ground at the earthquake.
In this report, soil improvement effect of grain material in the gravel pile as a measure against liquefaction was investigated. Tri-axial compression tests using uniform particle size grain material and in-situ testing were conducted. According to those results, it was clarified that both the dilatancy properties of less volume change and high permeability of the material can be considered in the design stage, and also are effective for the economical design of slab foundation structures.

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In order to prevent casualties in slope failure, it is one of the best solutions to monitor slope stability automatically through wired communication network. However, the automatic monitoring system has still many problems such as high cost, mobility and stability etc. Thus the system has not becoming popular extensively. We redeveloped the automatic monitoring system. It is expected that it would solve all the problems by using the portable phone. The system has been mainly composed of invar wire extensometer with essential mobile power set, and it could be applicable to the various sensors. We report a summary about the process of monitoring systems and its observation on dangerous slope.

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This paper describes the estimation of VFM of PFI for local road project in Japan.
At present, direct and indirect tax gain from dividend of shareholders of PFI project is not considered. Furthermore, opening of road service can be started earlier compared to non PFI project. Earlier road service can produce indirect tax gain.
If these taxes will be considered to PFI projects, and project cost can be cut down of 4-10%, with this scheme, VFM is attained.

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The dynamic response of load cell was studied so far through the m-k model which regards loading part and sensor as a mass (m) and a spring (k) respectively, and this model has a tendency to give very large output values near the natural frequency. In this paper, the frequency characteristics of load cell are investigated through impact tests using stepped rods as well as numerical simulations based on the multiple reflection theory, and as a result the frequency characteristics can be expressed by the primary decay model. It is also revealed that the output value diminishes as the input value increased resulting to the contrary to the former common sense in the frequency characteristics of load cells.

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