Several joints between footing concrete and steel sheet pipe pile wall have been used, but their shear transfer mechanisms of the joint have not been made clear fully under present conditions. Therefore small scale and large scale model tests with some different joints including a new proposed joint are carried out, and their shear transfer mechanism has been investigated based on tests.
Consequently, the proposed joint structure which has sufficient shear transfer capability and construction efficiency has been applied successfully at Katsushika Edogawa line, Metropolitan expressway in Japan.

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In order to find deformation capacity of reinforced concrete bridge piers under earthquake, cyclic horizontal loading tests were carried on the specimens of bridge piers for which span ratio, tensile reinforcement ratio, web reinforcement ratio and axial compressive stress have been modified, and the effect due to these factors against deformation capacity has been identified.
Furthermore, a study was made on the method to obtain ductilities for quantitative evaluation of deformation capacity of the reinforced concrete bridge piers, and a method capable of calculating thereof relatively accurately was proposed.

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In order to estimate the possibility of thermal cracking of concrete structures, various thermal crack evaluation indices have been proposed. These indices are calculated from the results of thermal stress analysis. However, these indices include a certain amount of error and the crack evaluation contains a certain extent of uncertainty, because the calculation of stress analysis has a certain inevitable error and, in addition, cracking has a probabilistic nature. In this study, thermal stress analysis was made for 43 cases of mass concrete structures with and without thermal cracking by finite element method. Effectiveness of the crack indices in evaluating the thermal crack occurence was fully examined. Three crack indices were adopted, which were defined by stress-strength ratio, strain-strain capacity ratio and thermal crack index proposed by JSCE.

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Studies were carried out to investigate the cracking properties of the tension zones of actual RC bridges. Crack spacings and crack widths of three different types of RC bridges were measured and statistically examined. Experiments using RC specimens were also carried out to evaluate the influences of tension and drying.
The spacing and the width in bending zone of actual RC bridges comform well to logarithmic normal distribution. A relation W_0.95 (95% fractile in the distribution of crack width)=aL+b was observed. Where a and b are coefficients and L is crack spacing. And according to the drying of concrete, both a and b increased. A formula giving the maximum crack spacing and maximum crack width of actual RC bridge was proposed.

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Simulating a part of prestressed concrete dual shell tanks, full-scale beam-shaped specimens were tested. The specimens of three types whose restraining condition at both ends were different were prepared. Rotation was restrained for the first ones, axial shrinkage for the second ones, and both rotation and axial shrinkage for the third ones. To give temperature gradient, the specimens were cooled with liquefied nitrogen from one side, when the opposite side was kept uninsulated and the other two sides were insulated.
Temperatures and stresses at the various locations of the specimens were measured. Besides, yield stress and ultimate strength were measured. The test results were compared with the analytical results, and it was found that the analysis might predict the behavior of the structures with sufficient accuracy.

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A total of 47 model slabs whose scale was about 1/3 to a typical deck panel between adjacent main girders of an existing steel-concrete composite girder bridge were tested under the repetition of a wheel load using a wheel tracking machine originally developed by Osaka City University. The tests were confined with a low cycle fatigue range in which the repetition of a wheel load was less than 2×10⁴ times. The numerous data obtained in the tests are used to reveal the low cycle fatigue characteristics of bridge deck RC slabs. Besides, assuming that such characteristics may also significantly control the high cycle characteristics of the slabs, a method for estimating fatigue strength and fatigue life of bridge deck RC slabs is proposed.

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Dyeing the products of the alkali-aggregate reaction made it possible to distinguish them from the components of the concrete under a microscopy. Cyanoacrylate mixed with a coloring substance was used to dye the alkali-silica gel red.
Cyanoacrylate reacts readily with water contained in gel but not with the components of the concrete. Examination of dyed thin sections revealed a few concrete cores with expansion of alkali-silica reactive aggregates. This method appears to be useful for observing the alkali-aggregate reaction.

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When we estimate the structural safety for earthquake motion based on the energy concept, there are many subject to be cleared. The most important subject is how to estimate the energy absorption capacity of structures. The authors have presented the quantitative estimation of energy absorption capacity of concrete columns. This is an experimental study to examine the way of evaluating the energy absorption capacity of reinforced concrete frames quantitatively. A set of five reinforced concrete frames were tested under five types of cyclic loading. The results developed in this study is intended to expand for the estimation of seismic safety of reinforced concrete structures.

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There are two theories to estimate the ultimate torsional strength of reinforced concrete members. One is space truss theory and the other is skew-bending theory. On the space truss theory it is convenient to derive the equilibrium and kinematric conditions and to develop the research of reinforced concrete member subjected to combined torsion and bending. This paper is an attempt to clear the torsional resistance of reinforced concrete members based on the space truss model. It is assumed that the angle of direction of cracking will be fixed so that shear strain is minimum. The three patterns of the failure by longitudinal bar, transverse hoop bar or concrete struts are determined by the conditions of the angle of cracking. From the results of the comparison of experimental and theoretical torsional resistance, the proposed theory is shown to be available.

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A 1/15 to size scale prototype of a PC dual shell tank for Low temperature liquid storage was fabricate. LN₂ was used as a substitute liquid for LNG in conducting trial experiments dealing with cooling, liquid storage failure after the insulation of material and other such similar case types.
In cooling it was demonstrated that the temperature difference was almost doubled at the corner sections.
In addition the prestressing effect due to the differential in liner expansion factors, between the reinforced steel bar and the concrete caused a tensile stress of about 1600kgf/cm² in the reinforcing steel bar.

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It is important to establish a technology for predicting the deformation of fresh concrete subjected to various external forces for saving manpower in concreting work through automation and systematization. This paper describes the analysis and the experimental results on the deformation of comparatively stiff consistency concrete in slump test taken as an example of the deformation subjected to static load. The results obtained from this study proved that it was fundamentally adequate to analyze and predict the deformation by assuming the physical properties of this concrete as a visco-plastic body estimated by cohesion and angle of internal friction. The condition for forming pipe body in centrifugal casting as a application of this method was also discussed.

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Permeability performance of surface treated concrete using synthetic resin is examined experimentally. Transmission rates of oxygen, liquid phase water and vapor phase water through surface treatment-concrete system are measured. And fundamental concept of durability design against reinforcement corrosion is discussed. The conclusions in this paper are summarized as follows; (1) Transmission abilities decrease with increasing surface treatment thickness and decreasing water cement ratio. (2) While, epoxy lining or MMA impregnation is a water proofing system, silan impregnation, silan with polymer cement mortar coating or urethane lining is a water phobic system. (3) Concrete surface treatment can't elongate the service life of chloride damaged reinforced concrete member, unless chloride contaminated cover concrete is removed.

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When regulated set cement concrete is used for various construction works, first it is necessary to know that property of revealing the strength the regulated set cement concrete shows.
Accordingly, this research was that which experimentally clarified what property of revealing the strength the regulated set cement concrete using a superprasticizer shows in the curing under low temperature, normal temperature and heating. Besides, the characteristics of revealing the strength of regulated set cement concrete were clarified by comparing with those of ordinary concrete, and the reason was considered chemically.

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Popout characteristics of concretes incorporating ferro-nickel slags as their fine aggregate were examined under various conditions for a long period of time. Of seven kinds of slags used in the test, three were found to cause the popout of concrete althouh the popout occured only when the concrete was stored under a moist condition. A particle of either white, whitish gray or reddish brown color was always observed to exist at the center of each popout. The X-ray diffraction analysis of the particle revealed that it was consisted of almost 100% brucite regardless of its color, indicating that the popout was caused by the hydration and the resulted expansion of some slag particles which were mainly composed of free MgO. The free MgO was considered to have existed in the molten stage of slags and remained unhydrated during their chilling process at their drawing time from furnaces. Some effective means of producing stable slags were also discussed briefly.

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In an effort to predict the load-deformation response of reinforced concrete elements subjected to pure torsion, an analytical model is proposed in this study. In this model, compressive stress-strain curve and tensile stress-strain curve of concrete struts between diagonal cracks are considered in equilibrium. Experiments were then conducted to verify the validity of this model. The experimental and analytical values have been found to be in good agreement and the proposed model is thus capable of predicting not only the strength but also the angle of twist, the steel strains and the concrete strains throughout the loading history. The concrete cover and the reinforcement ratio are also found to have significant effect on the change of shear flow.

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Compressive strength and creep behaviour of concrete with fly ash under steam and autoclave curing are evaluated with regard to the hydration between cement and fly ash. Concrete with 40% fly ash replacement shows almost the same compressive strength as concrete without fly ash under autoclave curing. Compressive strength can be increased by proper curing conditions in steam and autoclave curing. Reduction of water-binder ratio by use of a large amount of superplasticizer and use of fly ash classified by sieve under specified diameter are effective for improving compressive strength. Creep of concrete with 40% fly ash replacement is as same as that of concrete without fly ash during autoclave curing.

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The thing most demanded in emergency works is to accurately grasp the strength at early age after concrete is placed. The strength of regulated set cement concrete is affected by the cement content, temperature of placing concrete, atmospheric temperature, the quantity of concrete to be placed and so on, accordingly so far, it has been difficult to accurately estimate the strength at early age.
Therefore in this study, the method of accurately estimating the strength at early age of the regulated set cement concrete for emergency works was devised. Besides, it was clarified by using a statistical method what extent of reliability this estimating method has.

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It has been suggested that drying shrinkage of hardened cement paste, mortar and concrete is strongly related to mix proportion. The purpose of this experiment is to examine past theories about the relation between mix proportion and drying shrinkage, using many specimens made with various mix proportions.
The relations of factors of mix proportion, such as water content in the original mix, to drying shrinkage already pointed out by many investigations were also observed in this experiment over a comparatively wide range of mix proportion, except for lean mixture of extremely stiff consistency. These relations can be systematically explained by the theoretical law of drying shrinkage derived from multiphase approach. It is expected that the law can properly predict the effect of mix proportion on drying shrinkage of concrete.

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This paper describes the results of experimental research related to the strain and strength at failure of asphaltic mixtures by means of constant rate of strain flexure test, simple tension test, thermal fracture test under various loading and temperature conditions. A new method measuring fracture temperatures of asphalt due to thermal stress at low temperature (Moriyosi Breaking Point Test) and Fraass breaking point test were also conducted. In this study, it is concluded that the strain at failure is of an order of 10^-4cm/cm in the region of the brittle failure, and flexural strength of asphaltic mixtures around the brittle point decreases with decrease of rate of strain, and the strongest correlation is observed between thermal fracture temperatures of asphaltic mixtures and Fraass breaking point temperatures, Moriyoshi breaking point temperatures of asphalts.

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The effect of initial curing periods in water, the replacement ratio of fly ash and binder content on the depth of carbonation of concrete under accelerated carbonation condition is evaluated to predict the depth of carbonation of concrete under natural exposure condition. The depth of carbonation depends on these factors and it can be predicted by the effective water-binder ratio or compressive strength of concrete cured in water for 28 days. The test results of the accelerated carbonation test are compared with those of the natural exposure test. The depth of carbonation of concrete exposed indoors for 15 years has a good correlation with the calculated values by the equations proposed in this study. The depth of carbonation of concrete under natural indoor condition can be predicted by the accelerated carbonation test.

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This paper describes vibrating properties of ferrite-asphalt composite materials which were obtained through mixing ferrite byproducts with asphalt. The vibrating properties were measured by the fundamental bending vibration for specimen hung at the modal points. Following conclusions were obtained. 1) The higher the temperature, the larger was the logarithmic decrement, the smaller was the resonance frequencies and the smaller was the dynamic modulus. 2) The quality of asphalt had small effects on material properties comparing with the effects of temperature. 3) Logarithmic decrement had quantitative relationships with dynamic modulus.

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