The purpose of present study is to obtain the fundamental data of urethane grout for forepoling as one of the auxiliary method. Especially, the solidified shape of urethane grout was discussed in the model or real ground with various permeability coefficients. Firstly, the viscosity of urethane grout was examined in order to estimate the solidified mechanism. Secondly, the laboratory test on solidified shape, which had two parameters (permeability coefficient & foaming pressure), was carried out. Finally, solidified shape under the various ground conditions was verified in the field test. From the test result, it was ascertained that the permeability coefficient of ground significantly influenced the penetration mechanism and solidified shape of urethane grout.

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Recent years the damage of concrete structure has become big social problem. Therefore it is becoming increasingly important to work out a system for quality assuarance of concrete and to apply the system. Kyushu branch of Japan Concrete Institute has established a committee (June, 1999-November, 2001) on quality assuarance of concrete. The committe first look into the present state of affairs and the problems of quality control and inspection of concrete works, and then investigated the present techniques of concrete manufacturing and quality inspection method. Based on the results of the investigation, a quality assuarance system of concrete structure was proposed. In this study, the proposal of the commute is further investigated.

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Because the core sampling from the structure is difficult, test hammer is commonly used as non-destructive inspection (test) method for determining the compressive strength. But presumption error is said to be large, and it is the present state of affaires that this test method is not yet completely established. Therefore, in this study the various influence factors to non-destructive testing using test hammer are examined through model test specimens, model concrete girders and old constructed buildings. These data are then analyzed collectively. Based on the analyzed data an inspection method using test hammer is proposed for the compressive strength of concrete in structures.

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In the design for the retaining wall of deep circular shafts, the wall thickness, which greatly affects the costs of shaft construction, is usually determined based on the results of two-dimensional cross-sectional analysis. However, the standard structural model and design loads for such analysis, which allow the rational design of the wall thickness, have not yet been established. The authors performed cross-sectional analyses on five conventional two-dimensional models, to evaluate the appropriateness of these models and propose a rational two-dimensional model capable of faithfully reproducing the three-dimensional behaviors of the retaining wall for circular shafts.

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In recent years, the concern about the quality of lining concrete is increasing taking advantage of the crash accident of concrete. On the other hand, we thought that it is important to raise the construction nature for the improvement in quality of concrete lining. And we thought it is important to clarify the construction characteristic of the placing on consolidated fresh concrete.
From the above viewpoints, firstly, experimental study was carried out about the time of the placing on the consolidated fresh concrete and the influence of the different mixes on the characteristic of the placing on consolidated fresh concrete. Secondly, the optimal construction method of concrete lining was proposed.

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Regarding the more effective grouting of the foundation treatment for the highly permeable rock mass, it is very important to choose the better grout for the rock mass.
In this paper, showing that the conventional cement grouting is not good for the open jointed rock mass, the rapid hardening grout with adjustable gel-time, which has not been ever adopted in Japan, was proved to be more effective and durable over along period by means of laboratory, in-site testing and application of the newly developed grout to the dam site with highly open jointed rock.

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The purpose of this study is to inquire into the primary factor closely for running of a wheel system vehicle on terrain. So far the inflation pressure of an off-the-road tire was used as in constant under operation, and when the equivalent elastic modulus of a tire was higher than that of terrain the tire was regarded as a rigid wheel. The object of the test is 1000-R20 off-the-road tire to be set a pressure of 550kPa. The experiments on pure rolling were made running tests on soft terrain for 3-pattern inflation pressure. It was observed that the sinkage is accompanied by the set of the inflation pressure of the tire. Furthermore, it was clarified that even though the equivalent elastic modulus of a tire was higher than that of terrain, the tire shows the behavior of elastic wheel. As a result, the running performance of vehicle could be controlled by using the set of inflation pressure.

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In the Percussion Test, the damage detection of structure is performed by comparison of the design value with the estimation value of Young's Modulus of structure, ground spring constant and so forth. The estimation value is calculated by means of the structural identification method using measured response of the structure. In this paper, we have tried to estimate the ground spring constant and the extent of damage in bridge pier by using neural network method. The method is useful to decrease the labor in trial and error procedure of damage identification of structure and make it easy to apply soundness estimation method on the field immediately after the disaster.

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The effect of painting color gradation in reducing the resistance to the inflow of vehicles into the tunnels has been discussed in the past study. However, the influence of the painting with a reverse-course gradation has not been evaluated yet. This paper describes results of mental-evaluate experiments, conducted by using CG and video images. The subject of the discussion are tunnel portals, which was redesigned by painting with a nominal and a reverse-course gradation in order to reduce the resistance and consider the landscape. The study indicates the relation between the resistance to the inflow and the congenial driving environment. Moreover, it has shown the effectiveness of the redesign by painting with a reverse-course gradation.

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We developed a complex material to attenuate low frequency noise from 30Hz to 200Hz that occurs in steel girders. This method permitted us to reduce noise in the frequencies that affect steel girders, particularly in experimental construction project. The method reduces the time required for project completion, as well as construction costs. This paper describes the development process and techniques of the new method.

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Repair hysteretic data of the highway bridges is not effectively used in management system for the reason that repair hysteretic data is not accumulated enough. However, repair hysteretic data is effective information for planning of maintenance strategies. This study analyzed the relationship of repair frequency to the accumulated track traffic volume by using repair hysteretic data. Moreover, repair rate curve was identified by applying analytical results to logistic curve. In addition, long-term maintenance strategies were suggested by using the repair rate curves.

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In recently, some useful database systems have been developed for civil infrastructures maintenance management. In this study, the acquisition of the rule type knowledge concerning the bridge expansion joint deterioration is attempted by using the Knowledge Discovery and Data Mining (KDDM) technique from the databases. As the KDDM technique, the decision table abridgment, which used the concept of the rough sets, is applied to the extraction of the rule-type knowledge. Then it offers useful tools to discover patterns on the bridge expansion joint damages hidden in data stored in bridge-database. And also, several different domain experts have evaluated the results obtained by the KDDM technique.

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This paper presents a basic study on the modification control of differential settlement of a building with spread foundation by new cylindrical rubber jacks. This study is consisted of a model test, the numerical simulation and the control analysis. The water is injected into the cylindrical rubber and then it expands in the sand. The result of interaction analysis by the FEM was also compared with that of the model test. On the other hand, an optimal control analysis with the performance function was carried out. As a result, the phenomenon of jacking up by the cylindrical rubber jack could be predicted, and the applicability of the optimal control for the interaction problem could be confirmed.

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Recently collapse due to fatigue of steel sign poles on the highway bridges with rubber bearings becomes social issues. So we had a discussion meeting with different field's engneers, where reinforcing steel tubes with ultra-violet-curable resin sheets was proposed. In order to confirm the effectiveness of this material on the fatigue life, the static 3-D FEM analysis and full-size model tests with and without the sheets were conducted. As a results, a usefullness is recognized from both the analysis and the fatigue tests.

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Factor and level of a degradation must be grasped appropriately in order to maintain concrete structure. Therefore, various inspections such as visual observation and hammering test are carried out. On the other hand, the maintenance based on dynamic information (stress, displacement, etc.) will be also important. Then, some in situ stresses measurement techniques are proposed, and those methods are gradually applied in fields.
In this paper, more simply and accurately residual stresses measuring method is proposed.

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Bentonite has been attracting greater attention as buffer materials for repositories of high-level nuclear waste. The bentonite buffer blocks will be produced by compacting bentonite and/or sand-bentonite mixtures in the aboveground-factory to create the high dry density within 1.6-2.0Mg/m³. One method to produce the buffer is to apply the static high pressure to bentonite powder in the steel-mold. Some problems will appear when the production-processes of bentonite buffer block will be created. Therefore, this study clarified the some difficult problems by producing the scaled model of bentonite buffer blocks. Furthermore, the countermeasures of appeared problems are proposed in this study.

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In case of constructing the mountain tunnel, geological survey such as seismic prospecting and electrical prospecting is often carried out However, the support design based on these prospecting results is not quantitative, so it is often differ from actual geological condition. The other side, it is important from safety and economical efficiency to gasp accurately the geological condition beforehand in design and construction In this paper, the systematization of geological evaluation technique that converted from seismic velocity and electric resistivity to porosity and saturation was discussed As the results, the evaluation system of rock mass using the both of seismic velocity and electric resistivity are proposed, and it is recognized that this system can be applied on the in-site rock mass site.

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In the evaluation of ground improvement by jet grouting, the compressive strength test is generally employed by means of the boring core specimen, which can be obtained as a test cylinder. However, the ground improvement without such improve condition is estimated to be able to support a certain extent of load. The purpose of this study is to establish the evaluating criterion of condition of jet grouting, and to propose the evaluation method for ground improvement. Furthermore, the present study discusses the estimation method for strength of whole improvement of ground.

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The conventional single positioning method of GPS is generally not enough accurate for precise surveying. The authors have developed a method for measuring relative coordinates between two measurement points with better accuracy than the conventional one for the single positioning method.
In this paper, a new procedure of displacement measurements using the single positioning method is proposed. The trend model is applied to the previous method for smoothing the scattered measurement results. In order to verify the proposed procedure, numerical simulations with using measurement results are demonstrated for landslide displacement measurements.

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