Diagnosis expert systems have been constructed in various fields of civil engineering. In recent years, the technique for expressing deep knowledge of experts on the knowledge base have been important. In this paper, a inference-engine is developed by Franz Lisp language. The inference-engine is constructed by using the network model, which can create automatically tacit relations and may contribute the acquisition and refinement of knowledge base. This inference-engine is actually applied to infer damage cause of reinforced concrete slabs of steel highway bridges.

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In recent years, the computering in civil engineering had been applied not only in CAD but also in Expert System. But, they did not need a synthetic knowledges and experience of a designer such as comparative design which is judged a whole bridge by plural elements, and deviated from primary mean of Expert System or Artificial Intelligence. In this paper, we picked up superstructure, substructure, and fundamental structure of bridge as the object of this study, and proposed Expert System which introduced plural estimated elements which economics, workability, adaptablity to environment and so on. And the efficiency of the proposed system is demonstrated by the comparison between the result of this system and the past actual example of comparative.

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In this paper, the relation between the critical wind speed of coupled flutter Vs estimated by Selberg's formula and some structural elements of a truss stiffened suspension bridge was studied. It was clarified that the increase in lateral members' section, diagonal members' section and truss height effectively improves Vs without much additional cable weight.
Some very long span suspension bridges whose main span range from 2000m to 3500m were designed and approximate weight of those bridges was estimated. As the result, it was found that such a suspension bridge with 2000m-2500m main span can be constructed by enlarging the above-mentioned members which increase torsional rigidity of the truss girder.

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NATM is generally accepted as a standard method of tunnelling. In that method, standard patterns of supports are conceived for relatively high strength ground, but those for low strength ground are a subject for further studies. Tunnels in such ground are uniquely designed and constructed in the practice of trial and error. This study, to ensure a design method for NATM in such ground, proposes a sample method in which minimum excavation limit obtained from ground characteristic curve is used as an aim of optimum design and examines its availability to tunnel construction. Further, in the study, utilization of FEM is examined to enhance wider applicability of the method.

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In recent years, the rock fall disasters are taking place in large scale. So far, the investigations for the countermeasure against the rock falling have been mainly carried out through the interpretation of oblique photographs and field exploration. In many cases, however, the results obtained by these methods are often stereotyped and subjective. At present, there is an urgen tnecessity to carry out the investigation over the wide area of acute and dangerous slope land grasping it as a plane and with uniform accuracy. In this study, therefore, we discussed how to establish the investigation method by ground remote sensing and its possibility of applications, using thermal images of ground and aerial survey specifying a frequent rocksliding slope land as a model area, in an aim to perform safe and efficient investigation for the implementation of countermeasures against the rock fall.

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The objective of this study is to evaluate the accuracy of the land use capability classification with Latency Factor (LF) model developed by ourselves in 1990. In this LF model, we used not only Geographical Information (GI) but also the satellite data for the land use capability classification and explained the usefulness of the satellite data. In comparison with the accuracy of agricultural capability classification in case of only using GI and GI with the satellite data, it was found that the later is more useful for extracting appropriate areas. Furthermore, we proposed the new subtracted image made from extracting the different pixels between the capability classification images in the two preceding cases respectively. It was shown that the subtracted image is worthy of the new and wide application on the land use plan and planning.

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In order to establish methods for producing durable concrete, it seems to be necessary to make a detailed investigation on deterioration of exposed concrete structures in the field, besides laboratory experiments. In this investigation, a large number of road bridges were examined and many points which should be considered in the constructing and designing of bridges were found. The deterioration observed seems to be mainly caused by poor construction, but in many cases deterioration could be avoided by careful considerations to questions of design of concrete. It is expected that the details of structural design proposed here could be helpful in preventing deterioration due to freezing and thawing.

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The flow properties of cement grout of different concentrations and containing up to 5per cent of bentonite by weight have been measured in thin pipe over a wide range of pressure gradients. The flow curves obtained approximated to those given by a Newtonian type and/or a Bingham-type. The magnitudes of parameters such as a viscosity and/or an apperent viscosity and yield value increase very rapidly with the concentration of the grout and the increase of bentonite. From the results, it is recommended that the concentrated neat cement grout is suitable for the general case but the containing bentonite grout is preferable for the case of intending to prevent undesirable traveling of grout.

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A continuous composite girder bridge by using prestressed precast concrete slabs (PPCS-Method) was constructed at Osaka in 1989 as a first application to actual highway bridge in Japan. Firstly, the constructional procedures and the advantages of this new kind of bridge by using PPCS-Method are introduced herewith. Secondly, predicated are the outline of analysis, where delayed elastic and flow creep, and also creep recovery are exactly considered, and some caluclated examples on creep and shrinkage of this composite girder. Furthermore, the long term behaviors in indoor and field test on creep and shrinkage for this bridge during two years are reported together with comparisons as well as discussions between analytical and test results.

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In order to clarify the nature of the bonding mechanism between ice and asphalt concrete and to develope new techniques to reduce debonding resistance, a series of experimental investigation was conducted. Surface energy was varied by using various water repellents, and stiffness of asphalt concrete was varied by mixing crushed rubber particles with the asphalt. Correlations between these variables were investigated and the following conclusion was obtained. Reducing surface energy and/or increasing deformability of the asphalt concrete is an effective way to decrease interfacial bonding between ice and asphalt concrete. In this regard, use of water repellents or replacement of aggregate with rubber particles is a promising method to facilitate debonding of ice and asphalt concrete.

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The Japanese Ministry of Transport has been developing a wave power extracting caisson breakwater to absorb wave power and convert it into electric power. The caisson of the breakwater has an air chamber which is a wave power converter of oscillating water column type.
A test breakwater was constructed in the summer of 1989 in Sakata Port and the breakwater began the power generation in the winter of 1989. The caisson has the lenght of 20m and the rated power of the generator is 60kW. The system works well as designed. The experiment is being conducted successfully. In this report, the wave power conversion in the field experiment is described.

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This paper deals with the situation of pressurization of grouts in the ground anchor, paying attention to the fracturing of ground by the grouting pressure. Through the laboratory tests and the field tests, main conclusions are summarized as follows: 1) In the sandy ground, the fracturing hardly occurs, because the grouting pressure does not act effectively on the ground around the anchor due to the dehydration of grout, 2) In the clayey ground, the fracturing occurs if the unconfined compressive strength is not large enough. The experimental equation, which gives the fracturing pressure of cohesive soil, can apply to the fracturing pressure in the field tests. 3) The situation of pressurization of grouts is reflected by the relation between the injection rate and the injection pressure.

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In this paper, the load cell for measurment of impact load is made on experimental and theoretical basis, which is to measure impact forces propagating in soil and/or sand layer. Executing dynamic response analysis and making an experiment on impact test, its applicability to practical uses is discussed.
Finally, it is shown that the load cell manufactured here can be used to measure impact load pressure in which the maximum stress and frequency are 19.6MPa and 1kHz respectively.

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Recently, fatigue damage of steel road bridges is reported and their design method is going to shift from the allowable stress design method to the ultimate-strength design method. For this investigation, it is necessary to understand the actual characteristics of the traffic load accurately. This paper has made clear the characteristics of traffic lane and classified vehicle traffic load, respectively, as a result of analyzing a long term calculation of Tomei Expressway data from load cells.

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For the over populated cities, the use of a permeable pavement is considered to be efficient in environmental engineering, for example, inprovement of living environment, prevention of urban disaster and so on. Not with standing those social needs, the present permeable pavements are built mainly of an asphalt paving and their applications are limited to pedestrian walks and light traffic roads. In this paper the mechanical properties of permeable pavements applicable to heavy traffic roads were studied and a fiber reinforced permeable cement concrete pavements with stainless steel was developed with the aim of improving its bending strength and toughness. For purposes of its practical use, a field test was carried out based on the results of several laboratory examinations. The permeable plain concrete pavement was constructed in order to compare with the steel reinforced one.
Results of the investigation for 18 months after construction showed that the steel reinforced pavament was superior in bending strength, toughness, crack restriction to the plain one. As a conclusion, a new type of permeable pavement for vehicle trafficked roads was proposed using a roller compaction method. The design method, high cost, upkeep of porosity remained for the future discussion.

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This paper deals with internal resonance between longitudinal sway mode vibration and asymmetric vibrations of the girder for long span cable-stayed bridges. The seismic behavior is investigated by means of seismic response analyses using the response spectrum method on the cable-stayed bridge model with a center span of 800m.

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