There have been only a few studies on the basic brick composed of mainly limy materials, which are produced in large quantities in Japan.
Thus, using synthetic pure chemicals and commercial materials, some basic C₂S bricks composed of chiefly lime have been trially made, and the study on the antidusting agents of this brick and the comarative investigation on the properties of this trially made C₂S brick, alumina brick, Ritex brick, and chro-mag brick have been carried out.

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As the method for determining the tensile strength of mortar or concrete, splitting method is simple, but the question is left whether the values obtained show true, simple tensile strength.
From the stress calculation of the breaking section taking account of the effect of the width of imposed load and the experiments on the test pieces composed of two kinds of mortars, the author concludes that the values from splitting method may be used as a comparative measure of tensile strength of vaious mortars, but there leaves room from further investigation in order to use them as the true simple tensile strength of mortars.

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This report describes the relation of the viscosity of binder and temperature.
Author estimated the conditions in admixing process from the stormer viscosity-temperature curve and the isoviscositic curve.
This estimaion method is more simple and exact than customary methods, namely, experimental and chemical analytical tests.

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Author determined the softening point of pitch which mixed with coal tar or creosote oil by the ring and ball method.
The softening point of pitch desended straightly by adding of coal tar or creosote oil, and the descent rate of hard-pitch is greater than soft-pitch.
in the descent of softening point of pitch, the action of creosote oil is just two times of the action of coal tar.

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By hereditary characteristic is meant here a characteristic including both after-effect and hysteresis. By devising a proper dynamical model for the explanation of the dynamical characteristic of rubber vibration absorber, one of authors has given a physical meaning to the fundamental equation used by Boltzmann, Becker and V. Volterra. In the discussions, however, he concluded that the dynamic stiffness and equivalent viscous damping coefficient are independent of amplitude. There are of course such materials for industry that satisfy the conclusion, but generally materials should be considered otherwise. Here it becomes necessary to take the hysteresis characteristics into consideration. To meet the need, the authors propose a new dynamical model and with it new distribution functions φ(s) and ν(s). By the model and one of the functions the property of the socalled virgin curve and the correlation among the virgin curve, loading curve and the unloading curveare made very clear, and the physical explanation of the permanent set which is considered to be a plastic deformation become easy.

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This investigation was made to clear the various problems in fatigue by considering the true stress distribution during fatigue tests, which is derived from the stress-strain relation under fatigued state based upon many experimental results. In this report, the relation between the notch factor and form factor is described.

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