From the technical viewpoint of dam grouting, especially into soft rock ground, ineffectiveness of conventional cement milk grouting is greatly attributable to poor permeation of cement milk itself.
Field tests conducted at dams with soft bed rock foundation, have revealed that cement milk is injected along the cracks caused and enlarged by the grout pressure, what is called veined grouting.
Taking into consideration that air permeability of soft rock is quite high, laboratory tests were conducted to confirm that high air pressure changes the structure of soft rock and produces much more permeable passage of air (Tokido), and, therefore, seepage grouting can be achieved by sending dry cement particles with high pressure air into the “Tokido”.

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Representing the effects of maintenance by discrete jumps in the state variable, previous optimal control models for minimizing life-cycle costs for highway pavement maintenance were mathematically untractable and not used as a practical problem solving tool. This paper proposes a new solution methodology for this problem based on approximate continuous representations of road deterioration and maintenance relationships and costs of vehicle operation and pavement maintenance. The solution procedure is described in conjunction with a case study in which the Hamiltonian is linear in all control variables. The worthiness of the methodology is discussed based on a systematic evaluation of the solutions obtained through this methodology.

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In the Fukui Plain, the Main River Kuzuryu is flowed into by these branch rivers, the Asuwa and the Hino. In this paper, the authors calculate the unsteady flow equations of the three rivers using the data of the flood discharges in 1981 and 1983, and we further investigate the hydraulic characters in the middle and the lower courses of these three rivers with the results of the calculations. We can simulate a flood behavior from the results of the calculations and make it clear how the water-level, the discharge and the velocity change in these three rivers. Moreover it is also made clear that the stage discharge curve near the channel confluence points is affected by run-off-patterns by our simulation. The results of our research would contribute to the rationalization of river plannings in Japan.

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Construction of future express highways will be extended through the mountainous districts in Japan. Therefore, the number of foundations built on the mountain slopes will increase. Among spread foundations, footings with a stepping base, or so called “Dangiri Footing” are generally used. It is shaped like a stairway on the slope to reduce the amount of soil excavated and the area of cut slope. The authors conducted the loading tests on large scale models of Dangiri Footing, as one of the studies to establish the design procedure for the Dangiri Footing. In this paper, the test program and results are described in detail, and the simple failure mechanism and design formula to evaluate the ultimate bearing capacity are proposed.

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The present paper is concerned with the behavior of glued laminated grillage girder bridge with steel cross beam. The usual stiffness matrix method is used to investigate this problem. A method of analyzing the rigidity of composite cross section consist of wooden main girder and bolt for fastening cross beam to main girder is presented. Model tests and full scale experiments of Boukawa forest road bridge are studied experimentally and are compared with the numerical solutions. Through the comparison with model and field test results, the accuracy and the efficiency of this method may be verified, though the glued laminated deck panels were not yet installed at that field tests.

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In the slurry type shield, the cutting face is sometimes fractured by the excessive mud pressure and the mud suspension penetrates into the ground. This paper investigates this fracturing phenomenon through the fracturing tests as well as the blowing tests using the laboratory slurry type shield machine. And we clarified the value of blowing pressure in sandy soils as well as cohesive soils.

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In this study the system to measure three-dimensional static and dynamic deflection with 0.5mm accuracy from the distance of 50m to 150m away using a laser beam has been developed. The measuring system consists of two sets of theodolite with the launcher of a laser and the device which receives the laser. The system enables to measure the deflection along z axis as well as x and y axes. The deflection of a concrete arch dam caused by solar heat during a daytime is measured by this system, and the obtained results were discussed.

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For NATM tunnel construction method, it is very important problem to clarify the influences of drill bit wear on drilling rate of rotary percussion drill machine against several rock masses. Here, the fundamental relations between amount of wear and drilling time, and drilling rate and amount of wear have been investigated in laboratory test for granite, sandstone, andesite, diabase and quartzite by use of a small hammer drill bit. As an in-site test, the relations have been clarified for the same rock masses by use of several actual rotary percussion drill machines. As the results, the wear life and the critical distance drilled could be estimated by measuring the wear velocity of drill bit and the variations of drilling rate, or by substituting the bit diameter, the thrust, the impact energy, the index of rock mass strength for wear, the coefficient of crack and the radical compressive strength into the given equation.

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Successful conduct of any construction project requires management which will constantly guide the project toward its goal. Construction management has shown no sign of improvement, and little information has been published in spite of its needs. There seems to leave much room for improvement. Since each project will be under the influence of field, contract, and large scale production industry, construction management for projects should be versatile in every construction phase and process. In order to upgrade construction management, industrial management-oriented construction process control can afford to contribute effectively to this purpose.

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For urban subway construction shield tunnelling methods have become standard. Of these the pressured slurry shield method is perticularly often used because with this method it is easy to stabilize the cutting face.
It is important to predict the ground behavior caused by shield tunnelling in most cases where it is used very close to existing buildings or structures.
We have constructed 8 shield tunnels by this method since 1980. This paper attempts to explain the mechanism of ground behavior and proposes a method of its prediction based on past experience in the use of this tunnelling technic in stiff soil locations where ground movements have been monitored.

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This paper is written on the subjects of high-strengthing and thermal crack control of slurry wall. At first, this paper describes manufacturing and control method of high strength flowing concrete using low-heat-type cement, and then this paper investigates constructability of the concrete, degree of concrete segregation, compactability of concrete and characteristic of concrete strength which is placed into bore-filling slurry. As the result of mock-up test, authors obtained good quality concrete applying the method which authors propose for manufacturing and control of concrete. The concrete placed in the slurry showed desired results with high filling characteristics in spite of dense reinforcing bars.

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To clarify the trafficability and the traffic performance of a bulldozer operating on a weak terrain at driving and braking state, several vehicle tests were executed on a remolded silty loam terrain of 30% water content by use of a small tracked vehicle of 3.55kN weight, 71cm contact length and 20cm width of track belt. From the measured relations between driving and braking force, drawbar-pull and effective braking force, sinkage and slip ratio, it is clarified that the largest drawbar-pull is obtained at 3.2 grouser pitch height ratio and the locomotion resistance increases with the increment of slip ratio at driving state, and the sinkage under the rear sprocket at driving state is larger than that at braking state due to the large amount of slippage and the large eccentricity.

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Steel Bridges are temporarily assembled in shop yard at the final stage of member fabrication, so as to ensure the accuracy and connectivity of members. This process, shop assembly, demands huge shop yard and tremendous labor. In order to settle this problem, the authors have developed a system that performs the simulation of shop assembly, instead of assembling members in shop yard. This system consists of two subsystems which are measuring system and simulation one. The authors performed an experiment on the composit girder to demonstrate the validity and applicability of the system. The reliability of this system is verified through the experiment.

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Beppu bridge in Kyushu district which forms part of the Kyushu transverse highway from Nagasaki to Ohita, is a concrete arch bridge with a main span of 235m. Construction site of the bridge is in a famous hot-spring region and in severe corrosive conditions. It is required to construct durable concrete structures especialy for the foundation of the bridge.
The abutments of the bridge are massive structures having the dimension of about 40×35m and 23m height, so it is very significant in constructing the structures to control thermal cracks resulting from the heat of hyderation. According to the examination of the thermal stress analysis, some construction practices were taken to control these type of cracking.
Practices used included precooling of the concrete using flake ice as part of mixing water, use of low-heat type of cement and reinforcing outer sides of the abutments in order to restrict the size of cracks.

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Because the availability of disposal area is extremely limited in urban areas, utilization of excavated waste/surplus soils from road works was an urgent consideration.
In order to overcome this problem, the members of the Osaka City Public Works Bureau developed a soil recycling plant in 1982 which is able to crush the excavated soils including lumps of concrete, asphalt mixture, etc., screen them and mix them with quicklime to improve the stability.
The plant has a rated handling capacity of 100 tons of soil per hour. So far, about half a million tons of recycled soils have been produced by the plant, and have been utilized for base course, backfill and subgrade. This paper refers to the background to the recycling of soils, the recycling systems and the successful results.

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The vertical shaft of Kamome shield tunnel is excavated into 50m depth using the extra-deep diaphragm wall and inverted lining method. This is one of the few extra-deep vertical shafts ever constructed in Japan. Construction work is proceeding with the repetitive circle of measurement for the behavior of extra-deep retaining and cut-off wall with the depth of about 80m and the quantity of permeation. In construction site, there exist some alluvial clay layers which are now under consolidation and fissured diluvial clay layers. Therefore, some kinds of countermeasures are taken against expansion of clay layers and failure of vertical sides of slurry-filled deep trench under construction.

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The diaphragm wall has been adopted for foundation treatment at more than 70 dams in the world. Materials for these diaphragm walls have been of various kinds such as soil slurry, plastic concrete and normal concrete. In consideration of structual and economical conditions the TADAMI dam constructed diaphragm wall of plastic concrete in the deep alluvial deposit. In order to investigate the adaptability of plastic concrete to a cut-off wall for fill dam laboratory tests and field tests were performed. The result shows that the diaphragm wall of plastic concrete possesses adequate watertightness as a cut-off wall and close deformability to that of the alluvial deposit.

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