The Sydney Harbour Tunnel for a solution to Sydney's cross-harbour traffic problem is now under construction by immersed tube (IMT) tunnel method, on the east side of the existing Harbour Bridge. IMT units are cast in drydock at a distance of 90 kilometers from Sydney and towed to Sydney Harbour to be sunk. In this towing situation, IMT units are encountered severe waves because of open-sea towing. Therefore, stability of the unit against the wave-indused motions is the principal subject. This paper deals with the characteristic of unit motions and towing force based on model towing tests, and is considered to be applicable in real works.

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Reseach on the land use investigation using satellite data is being carried out very actively. We have developed “Latency Factor (LF) model” for the land use capability classification and evaluation. Points to which special attention should be paid are that satellite data and geographical information are defined as latency factors in the land. LF model doesn't evaluate a value in use of the land but a potential value or a value of existence in the land. The analysis processes are as follows: 1) Quantification Method Type III are used to analyze the causality between latency factors. 2) The land use capability classification map is made by Quantification Method Type II and the min-max method distinguishing areas resembled training data.
Furthermore. LF Model has the three evaluation processes called “Present situation type”, “Normative type” and “Hypothetical type”. By comparison of classification maps of the farm land made by LF model and the former grading method. LF Model is very useful for extracting appropriate areas.

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The expansion work of the Tokyo International Airport is now going forward which will increase its capacity. Nine bridges are being constructed there to link terminal buildings and car parks as well as main roads. The Air-Side Bridge is a 2-span continuous steel cable-stayed bridge with a center span of 88.5m. This bridge has been designed taking its landscape into full consideration, particularly to match surrounding facilities, the characteristics of the airport itself, and so on. As the results, the bridge has been fabricated by all-weldind work at every joint on the site. Since the bridge is the first all-welded one in Japan, the execution has been fully controlled. This report presents the structural features and the work control system of that bridge and its results.

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There are many studies on application of fiber reinforced plastic rods (FRP rods) to the reinforcement of concrete members. Those fibers have high tensile strength, light weight and excellent corrosion resistance. But, they have also some defects such as low modulus of elasticity and low bond strength.
The authors have conducted the researches to utilize braided AFRP rods made from aramid fiber as PC tendons under static loading. It would be effective to improve the composite action between rod and concrete by means of braiding the fibers and using them as PC tendons. In addition, application of spirally formed shear reinforcement keeping the continuity of fibers have also investigated. On the otherhand, there are few past researches on the fatigue characteristics of members reinforced by FRP rods, subjected to shear force under cyclic loading.
In this paper, fatigue characteristics of concrete beams reinforced by braided AFRP rods are discussed from the experiments.

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The authors have developed the expert system to make construction planning for shield tunnelling method skillfully and rationally. As tunnelling conditions and technologies have been diversified in recent years, the knowledge of expert engineers has been accumulated. By utilizing the knowledge base from such expertise, this system can support construction planning and design shield machines automatically.
This paper describes the motive for introduction of expert system, the method of making the knowledge base and the details of this system. The authors have estimated the application of this system to actual construction planning.

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This paper describes various factors influencing abalones gathering to the shelters. The experiments were carried out in the laboratory by using abalones and shelters which were produced through mixing fillers with many kinds of binders respectively. Following conclusions were obtained. 1) Abalone prefered the shelter with abalone mucus to the cleaned shelter. 2) Gathering rate of abalone to the shelter did not depend on the binder characteristics and particle size of ferrite by-products. 3) The higher content of ferrite by-products and the higher density of shelters, the more abalones were drawn into the shelters. 4) The abalones did not cling to small size of gravels.

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It is necessary to investigate the existance of obstacles or geological structure in front of a shield tunneling machine, especially in case of tunneling under the urban area or sea-bed. Accordingly, some field experiments were carried out for the purpose of developing a monitoring system regarding obstacles in front of the machine. Tow methods which use an acoustic wave and Rayleigh wave respectively, were examined. As a result, both methods were proved to be useful for detecting obstacles in size of 40cm in diameter or more and exist in the maximum range of 7-10m. Joint application of the both methods is expected to improve the reliability of the judgement.

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The Four-lanes widening construction in WAKATO bridge is to change RC slab for steel deck with assuring the regular traffic to run. Some problem about it were studied before this work technically or constitutively. We should reported here of an observation result and management of deformation caused by the variation of load system. In the meantime, the variation of vibration characteristics, the affection to stability of active and wind-standing with the construction are also dealt with. The result was that it is a best method for deformation management to use a water-level connecting pipe that made the measurement data in accordance with the calculation almost. Therefore, the method and procedure of construction this time may be thought adoptable. On the other hand, the vibration characteristics has no any difference with widening. Stability of the widened bridge with wind-standing equipment is better than it was.

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This research regards the analysis of the low frequency sound radiated from simply supported highway girder bridges when a vehicle traveling over them. First, running experiment was carried out using a test vehicle on a composite girder bridge, and investigation into the vehicle model which is proper for calculating radiated sound was performed. Next, by vibrating actual bridges using impact, the frequency response function were determined. The method of calculating radiated sound by utilizing the frequency response functions was proposed, and its applicability was confirmed. Finally, on the effect that the degree of roughness on bridge surfaces and the irregularities at the expansion joints exert to maximum SPL being radiated numerical analysis was carried out, and it was elcuidated that the SPL varied in close response to velocity parameter α.

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A sand layer has been usually laid on rock sheds as shock absorbing material against a falling rock. However, recently new shock absorbing materials have been expected against a big impulsive force. This time, the shock absorbing behavior of the expanded polystyrol against a falling rock is experimentally investigated.
Experiments have been carried out for the following four types of arrangement.
(1) Expanded polystyrol blocks only.
(2) Alternate layers of sand and expanded polystyrol blocks. (3) Sand layer only.
(4) Protection methods of the surface.
From the experimental results, the formula for the impulsive design load are proposed when the expanded polystyrol is laid on the rock sheds against a falling rock.

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The aim of this paper is to predict the wear life of the parts of centrifugal pump for slurry transportation, used in a shield tunneling work, in order to set up the pump parts management and supply system. In this study, some factors affecting the wear of pump parts, including grain size distribution, quartz content, amendment roundness of slurry particles and the pump rotational speed, are considered. Based on the study about these factors, equations estimating the wear amount of frontliner and impeller are proposed. These estimation equations are also applied to anather case.

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This paper describes effects of color on abalones gathering to the shelters. The experiments were carried out in the laboratory by using abalones and colored shelters. Following conclusions were obtained. 1) The color attributes of the dry shelter surface were similar to those of the wet shelter surface. 2) Gathering rates of abalone to the shelter were similar, if the color attributes were the same. 3) The lower lightness of shelter surface, the more abalones were drawn into the shelters. 4) The lower saturation of shelter surface, the more abalones were drawn into the shelters.

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Based on the results of laboratory and field tests for concrete in Roller compacted Concrete Pavements, it was found that:
(1) The quality of the fresh concrete can be determined using a slightly modified version of the VC test and the compaction method used for concrete in Roller Compacted Dam concrete.
(2) The degree of compaction in speciments for quality control and the actual concrete at site can be determined from the modified VC values.
(3) The strength can be determined from the degree of compaction and the water/cement ratio.
(4) Among the parameters in mix proportioning, the volumetric water to cement ratio, the ratio of the amount of cement paste to the air voids in the sand, and the ratio of the amount of mortar to the air voids in the aggregate are the ones that affect the modified VC values.
From the results of these tests, regression equations are proposed to estimate the consitency and the compressive strength of the concrete when the mix proportion is varied. Also the methods to suitably modify the mix proportion to obtain the concrete of required quality are discussed in this paper.

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This study was carried out to provide the basis for establishing a rational design method where requirements of both safety and economy in tunnel construction for the low strength deep ground are compatible. For the economic consideration of the tunnel construction, excavation works should be taken account as well as the support. Based on ground characteristic curves describing the relation between support pressure and ground displacement, following two curves had been developed for the checking of the design. One describes the relation between ground displacement and excavation limit which had been obtained by the sum of designed inner section, linning thickness and ground displacement. Another describes the relation between construction cost and ground displacement. The result of the study shows a better design indication for minimum excavation limit rather than minimum support pressure.

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Earthquake damages of aerial electric power distribution facilities in Japan were investigated, and factors contributing to the earthquake-proof of the facility components and ground conditions were identified for the various pole types, ground surface and layering, and foundation penetration depth.
Deformation characteristics of pole-ground coupled system was evaluated by in-situ horizontal cyclic loading test, and parameters required for seismic response analysis of the aerial electric power distribution facilities were derived.

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Although blasting is an effective method of fracturing rock mass, the method involves tremendous shock waves and noise. Due to recent increase in rock excavation near residential areas, there have been growing demands for alternative methods of excavation to avoid excessive noise pollution. A new static fracturing method of rock excavation and demolition of concrete structures using pressurized fluid was developed to satisfy such demands.
This paper describes the outline of fracturing machine and fracturing system used in the method, function check experiments of the machine and applicability of the method to rock slope excavation and demolition of top of concrete piles.
It is confirmed that the method shows sufficient function to fracture rock mass and concrete structures.

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Mechanical behavior of reinforced soil by continuous fibers is examined by means of three types of soil tests. According to the test results, effect of fibers mixing into the soil comes out as apparent cohesion of the soil and magnitude of it depends mainly on mixing ratio of the fibers. Degree of tension of the fibers in the soil and relation between size of particles of the soils and thickness of fibers have also great influence on the value. Reinforced soil by continuous fibers have an anisotropic behavior concerning the shear strength, which is induced by mixing process of fibers into soils. Influence of the fibers on coefficient of permeability of the soil is almost negligible.

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Large-scale model tests were carried out under artificial heavy rain conditions to study the behavior of 5m high steep slope embankments having soil-walls reinforced by continuous fibers. The erodability of the soil-walls and the stability of the embankments were examined. According to the test results, it was concluded that the soil-walls reinforced by continuous fibers are highly resistant to erosion due to rain and that the stability of embankments having soil-walls can be analyzed basing on circular slip method and conventional design method for concrete retaining walls if soil-walls are thick enough.

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In recent years, Observational Construction System (OCS) supported by monitoring and data processing system has increased importance for construction management. The purpose of OCS is to ensure safety and quality control and further to find out the optimum construction method by promptly feeding back the results of measurement to design. In spite of the importance of the method, there are few evaluation method for OCS because of the difficulty in analyzing the effect of the system.
The aim of this study is to take up the method of quantifying the effects of the use of the OCS from a view point of prompt alteration of construction method by monitoring and processing data. This paper discusses the characteristic of OCS and the method of quantifying such effects by cost-benefit analysis. Finally, this paper also shows the availability of the proposed method through the application for actual NATM works.

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Antiwashout underwater concrete is recently used due to the demand for speedy marine construction work of large structures.
Antiwashout underwater concrete was also used for the construction of foundation for the main towers of the Akashi Kaikyo Bridge and its excellent properties have been verified. The antiwashout underwater concrete, for large-scale pouring, must retain its consistency for long hours, have low heat of hydration and stable placing properties.
This study clarifies the effect of aggregate, sand, cement, and admixture on the flowability and setting time of concrete, and a better mixing method was developed to improve the quality of the antiwashout underwater concrete.

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In this paper field tests of the Meiko-Nishi Bridge which is a 3 span continuous steel cable-stayed bridge having the center span of 405m are dealt with. A simplified cable anchorage using steel pipes to the steel box girder rather than to cross beam is adopted in this bridge.
First of all, measurements of deflections and stresses at the towers, girder and cables are discussed to check the rigidity and safety of the bridge. Then, stress distribution measurements at the cable anchorage during cantilever erection small segments and after construction are described, which were performed to capture the local stress distribution. The field test results are compared with those of the numerical calculations by the FEM and the design procedure.

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Generally, supports for mountain tunnels constructed by NATM apply “Standard support patterns” due to the results of geological survey. Under existing circumstances, there are many support pattern alterations under construction. In this paper, we investigate the situation of support alterations in tunnels constructed in Granite, Slate, Schist mountains, respectively. Results obtained from the investigation indicate that the elastic wave velocity of the ground is the most effective parameter in the preliminary design of supports, but constructed support patterns barely correlate it and supports tend to alterate more safely under construction. Still more, we tried to find the factor of alteration and make a proposal to improve reliability of preliminary support designs for tunnels.

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The design of civil engineering constructions extends to wide range. Each design drawing has so different contens that such drawings all by hands needs highly skill. It is said now that technical labor powers are short. And experiments of auto-drawing supported by computer systems have been carried out in many fields. The author examines a method to manage labor shortage by introducing auto-drawing systems and tries to compare its cost with the cost of hand-drawing systems.

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Rational construction methods of concrete dam are currently being studied and some practical placing methods of concrete are already suggested. However, research upon concrete placing the travelling tower crane has not been in practice.
The automatic placing system of concrete consisting of the travelling tower crane is proposed in this study and structure of the system and working principle are discussed. Applicability of the system into the practical construction has been also confirmed.

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The 66-storey UOB PLAZA Building in Singapore will be founded on 12 numbers of deep and large diametered caisson type piles. The construction of these massive shafts in the ground, within close proximity of each other and in a densely built-up business district boasts of several technical accomplishments, namely.
(i) extremely short construction time of 12 months
(ii) stringent thermal crack control of concrete temperatures in each shaft using 270kg/m³ sulphate resisting cement.
Continuous mass pour volumes from toe to cutoff are up to 1800m³.
(iii) extensive full scale friction tests on the outer-shell lining to confirm designed friction values between the bouldery clay and caissons.

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This paper proposes the system in which the segments can be conveied from the stock yard to the erector at the rear of the shield machine without manual operation. This system consists of the following components:
1) Battery-operated carriages controlled by the central control unit automatically
2) Automatic segment-stock-rack device
3) Elevator installed in the shaft
4) Segment-supplying device placed at the rear of the shield machine
5) Central control unit and optical fiber communication system
The construction sites that emploied this system resulted in labor-saving and safety in work condition.

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For the foundation of the large bridges connecting Honshu and Shikoku, excavation for the 2P and 3P piers of the Akashi Kaikyo Bridge, following similar work on the Seto Ohashi Bridge, were carried out using a large scale grab dredger. High accuracy was achieved, leading to success of the laying down caisson method.
Large scale grab dredger have demonstrated their ability to dredge conventional navigation channels, particularly in excavating bedrock for the navigation channel through the Kanmon Strait. Consequently, the method was adopted for the underwater bedrock excavation of bridge piers for the Kurono Seto Bridge, the Seto Ohashi Bridge and the Akashi Kaikyo Bridge.
This report describes the transition of grab dredger and the bedrock excavation of bridge foundations.

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In order to construct a geogrid reinforced embankment on soft ground, it is significant to forecast its deformation in terms of the function as well as to evaluate safety factor. For that purpose, pull-out resistance of an embedded geogrid must be grasped. Even if various geogrids have the same tensile strength, they seem to display the different reinforcement force depending on their geometrical forms and surface states. In this paper, firstly the interaction between soil and a geogrid which affects pull-out resistance was examined based on pull-out test results. Secondly, influence of the material properties on the stability of an embankment on soft ground was analyzed from two aspects of reinforcement force and embankment deformation. As a result, the importance of the material properties for the stability evaluation was shown.

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