As one of moulding methods of cement mortar plates, there is vibrated moulding. In this case, we have two methods, without load or with load and I comfirmed, in 2nd report the latter method(with load) was superier to the former method (without load), but small load was all right. In vibrating moulding with load, next four conditions are very important-frequency, amplitude, vibrating time and load. When the vibrating is regarded as a simple harmonic motion, the frequency and amplitude are represented by acceleration and above four conditions become three conditions-acceleration, vibrating time and load. In this report, I researched the effect of above three conditions on the bending strength of mortar plates by experiments. In conclusion of this experiment, I obtained a experimental formular as follows. [numerical formula] where f: bending strength of plate α: acceleration of vibration T: vibrating time W:load k,n: Constant numbers In addition, I obtained the relations between the bending youngs modulus, unit volume weight, void ratio and the bending strength of plates.

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Confined shrinkage and free shrinkage tests have been made with specimens of concrete containing ordinary and light-weight aggregates. The conclusions obtained are: The amount of free shrinkage corresponding to the appearance of confined shrinkage is about 0.04% for concrete of ordinary aggregate and about 0.06% for light-weight aggregate concrete. The cracking of light-weight aggregate concrete is delayed as compared with that of ordinary aggregate concrete, while, once the crack has appeared in the former, the width thereof is larger and it may be more deterimental to the structure.

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The author's sound velocity method and its application for determinating the sound velocity in concrete were described in the Transactions of the Architectural Institute of Japan, No. 51. In this paper the relations between the variation of sound velocity in mortar specimens and the compressive strength are considered under various conditions and ages of curing. In computing the dynamic modulus of elasticity from the measured longitudinal sound velocity based on well known relationships, it is necessary to correct the value of the modulus with a factor which depends on the sectional shape of the specimen, and the factor is obtained in this paper from the experimental results of velocity and (sonic) vibration measurements for specimens with some typical sectional shapes. The relations between the static modulus of elasticity and the dynamic modulus computed from the resonating sound velocity are also presented. It is found, however, that these two moduli do not necessary agree wtth each other. It is shown that the effect of the moisture content of a specimen on the sound velocity is insignificant whether the specimen is saturated or in dried condition at the time of test, whereas the water contained in the mortar has considerable influence on the dynamic modulus of elasticity measured by the sound velocity method.

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In this report the results of experimental studies are shown with respect to the settling of wet concrete with crushed stone and with respect to the bond between such concrete and steel bar. The results of the experiments are shown in the following: (1) Main factor governing the settling of wet concrete are its consolidating characteristic which may be represented by its unit weight and its water content which is most affected by water holding capacity of light-weight aggregate. The capacity depends on the shape of aggregate and the distribution of void space. (2) For the purpose of reducing the amount of settling of wet concrete, it may be effective to minimize the water content of concrete without changing the consistency by means of adding AE agent or fly-ash in the concrete. However, the quantity of fly-ash to be added as a substitute for cement should not exceed 15% of the weight of cement. (3) Since the settling of light-weight aggregate concrete is governed by water-holding capacity of aggregate, the amount of settling may be small if a certain kind of light-weight aggregate is used. (4) The settling of wet concrete causes unfavorable effect to the bond between concrete and horizontal bar. (5) Retamping of wet concrete is an effective measure to improve the bond between concrete and lower side of horizontal bar. It should be noted that inner revibration sometimes affects the bond unfavorably when the concrete is liable to settle. (6) The bonds along upper and lower side of horizontal bar and those along hoizontal and vertical bars have been compared, and the relationship between compressive strength of concrete and bond strength along holizontal and vertical bars have also been determined by means of a new method of measurement.

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In the Transactions of A.I.J., No.51, the author has stated the principles of progress control in construction that (1) when the construction work has been delayed, the path which the actual progress curve should follow must be within the cross-hatched area and (2) the tangent of the actual curve should always be kept on the left side of point b after passing point a. In this paper the author states a few remarks on those principles in reference to practical examples. In cases shown below the construction work can kept on punctually, even though the above mentioned two conditions are not satisfied at the same time. Namely, I. When only the condition (1) is satisfied; (A) a case that the tangent of the actual curve is not kept on the left side of point b and also the tangent of the scheduled curve is designed in that way, or (B) a case that the tangent of the actual curve deviates from point b owing to extraordinary progress, II. When only the condition (2) is satisfied; (A) a case that the actual curve is not within the cross-hatched area at the early stage of construction period, or (B) a case that the actual curve is not within the cross-hatched area at the early and middle stage of the period.

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In this paper the authors propose the principle of a new earthquake resistant design of the lightweight construction with the original bracings of twisted wires and pretensioned wires. These aseismic bracings must be so designed that the regidity of building structure is properly distributed in each story to avoid distorted vibrations of the structure. Then, it may be expected to avoid the collapse of structure due to resonance when destructive seismic waves are encountered, since the anti-resonant property is given to the structure by the original bracings, that is, the structure becomes to have variable natural period owing to hard-spring characteristics of twisted wires and partial failures of pretensioned wires which, have initially contributed to the rigidity. In order to verify the anti-resonant property thus developed, the solutions of fundamental differential equations for the structure are discussed qualitatively. As the results of those mathematical analyses based on author's improved delta method, we can not only confirm expected nonlinear behaviors of the structure but also may suggest the uncertainity with respect to the existance of so-called jumping phenomenon in nonlinear vibration systems. From the analyses discussed above it may reasonably be said that the artificially nonlinearized structure of this type is a new device for aseismic construction.

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While the theories of vibrations of cylindrical shells have already been given by several authors, they are so complicated that very few cases have been solved actually, except such special cases that the displacement is in periodical from in both circumferential and longitudinal directions. When we are to deal with the vibration problems of cylindrical shell roofs, rather a simplified theory is often desired from the standpoint of practice since actually boundary conditions on the longitudinal edge are too involved to be dealt with mathematically. For this purpose of simplification approximate formulas are presented in this paper under some plain assumptions that only normal component of acceleration is taken into account whereas other components are neglected. Further, Zerna's approximations are also used. Then, the approximate theory thus obtained is applied to the cylindrical shell simply supported on stiffening walls which are rigid in their planes and flexible in the normal direction. Discussing the accuracy of this theory with the characteristic equation, we find this formula is applicable to the problem of shell vibration, if frequencies are low and shells are not extremely long. The frequency equation can be solved by trial method. As an example, the problem of free oscillations of shells are solved, whose longitudinal edges are free. On the other hand, experiments have been made and the results have been coompared with the above numerical example, showing good coincidence with respect to modes and frequencies. It will be said from these results that here presented approximate theory is sufficiently accurate to be used practically.

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有壁無壁ラーメンより構成されている建物で、耐震壁間の距離が大きくなると、床版が水平方向に曲げ及び剪断変形をするため、壁体間の中央部分にあるラーメンは、壁体附近にあるラーメンよりも其の変形が著しく大きくなり、その負担剪断力も著しく増大する事が考へられる。従つて、地震力による各垂直構間の横力分布は、従来の床剛仮定時の分布法では不充分である。この事柄を、一層建築物について取扱いました研究は、今まで二、三見られるのでありますが、本文に於いては、二層建築物の場合を取扱い、その一般的性質を明白るにすために理論的検討を行い、この様な問題に対する将来の設計上の指針を求めようとするものである。解の誘導に当りては、床版の変形は剪断及び曲げ変形を考慮するも、特に床版の曲げ変形に対しては、式の取扱いの便宜上、端部条件を固定とし、又桁行方向の抵抗(桁行方向に配置されたる耐震壁、柱…壁付柱、梁…壁付梁等)は無視すると云う仮定をなし、加力時に於ける床版の変形の連続性、弾性比例の法則、力の釣合条件より、屋根床版及びII階床版に就いて、各々差方程式を導き、この方程式の聯立と、耐震壁との連続性の境界条件より解を求めたものである。内容としては、[I]建物の両端に耐震壁を有する場合[II]建物の両端及び途中に耐震壁を有する場合[III]建物の一端及び途中に耐震壁を有する場合に就いて、それぞれの解を求め、梁行方向のスパン数の種々変化せる場合、壁体剛性の変化せる場合等の数値計算例を行い、且つ、これ等の値を床剛仮定値と比較した。更に、或階に作用せる地震力が、他階の床版変形に如何なる影響を与へるかを調べるための数値計算も行ひ、床版変形の横力分布に及ぼす影響を具体的に検討せるものである。

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This paper is the continuation of Part 1 written by the same authors in Transactions of A. I. J., No. 51, Oct. 1955 In the preceding paper (1) shearing regidity and (2) load of crack appearance were discussed with respect to almost full-scale specimens of reinforced concrete bracing wall. Based on the test results of those specimens, (3) maximum load carrying capacity, (4) ultimate strength and (5) effect of reinforcement are discussed in this paper. Results of test and conclusions obtained there from may be briefly summarized as follows: (1) When the enclosing frame has sufficient strength to resist external shearing force still after the inner wall has been cracked, total maximum load carrying capacity can be represented by average unit shearing stress equal to 0.22Fc where Fc is compressive strength of concrete. When the thickness of wall exceeds a certain limit in comparison with the dimensions of enclosing frame, the frame fails together with the inner wall when maximum load carrying capacity is reached. (2) With respect to ultimate strength of bracing walls many things have been left for further investigations. In the present state, however, it may not safely be expected that, in ultimate state, any additional strength is afforded to a frame by the wall enclosed therein. (3) Some of reinforcing bars in bracing wall are broken due to tensile stresses increased beyond yield point before maximum load carrying capacity of the wall is reached. Whatever the amount of reinforcing bars may be within the range of common practice, they do not serve to delay the appearance of cracks nor to improve the rigidity of the wall after cracks have been once appeared.

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Some data are presented for designing curtain wall enclosed in rigid frame.

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In this report are presented the results of a series of tests on strength and stiffness of SUGI (Cryptomeria) rubjected to rapis loading and long-time loading. The tests have been continued since 1949. In rapid loading tests, loads were applied by suddenly removing a support at one end of a catilevered beam with a weight connected thereto. Consequently, some beams failed (the time to failure was about 0.2sec) and some were vibrated without failing. In the latter cases the same loading procedures were repeated until they failed eventually. Long-time loading tests or "creep" tests were carried out under natural air condition and dead loads were sustained for 6 to 10 months at the free end of cantilvered specimen. The conclusions obtained are: (1) Modulus of rapture due to bending increases (decreases) as the time of loading decreases (increases) below (beyond) that under normal static loading. Within the range ofl oading time from 0.2 sec up to 10 months. The increasing (decreasing) rate of modulus of rapture is approximately 9% for a tenfold decrease (increase) of loading time. (2) The effect of long-time preloading on modulus of rapture under normal static loading is not disclosed. (3) When a specimen has been vibrated until it fails, the failure load gradually decreases as the number of repetition of vibration increases. (4) Modulus of elasticity under rapid loading is in general increased to some extent(less than 20%) than that under normal static loading. On the other hand, static modulus of elasticity for specimens subjected to long-time preloading are decreased, whereas those specimens show brittle behavior in their loaddeflection relationship, in other words, something like work-harnening effect is observed. (5) Deflection at maximum load is somewhat smaller under rapid loading than under normal static loading. (6) Specimen of cryptomeria subjected to bending fails under the load corresponding to about 60% of the normal static modulus of rapture after such load has been sustained for 6 to 10 months. (7) When a specimen is reloaded after the sustained load is completely removed, it shows increased modulus of elasticity corresponding to the amount and the time of sustained preloading.

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In this paper results of experiments with respect to deformation between column and its base plate which was specified in Report 1 are shown. In those experiments welded and riveted specimens were used; one of each was given simple bending and the other was acted upon by eccentric loading. The columns were connected to the both sides of base plates, the centers of column and base plate coinciding with each other. When the connection was riveted remarkable deformation was observed between column and its base plate while no deformation took place in the case of welded construction. It was also confirmed that axial force in column had the effect of reducing the rotation of column base.

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In this study the author considered (1) the reason why "Tsuchi-mikado-dono" was used as Imperial Palace in early 14 C.A.D., (2) the scales of its site and buildings, and (3) the plan, the function and the character of "Ko-go-sho" in the same Imperial Palace "Tsuchi-mikado-dono". In conclusion, the antecedent of this palace "Tsuchi-mikado-dono" was the Palace of "Yo-toku-mon-in", a member of Imperial families, and this building continued from 1317 to 1401 A.D. as Imperial Palace. As a result, we could find a type of Imperial Palace in the Northern and Southern dynastic period and a type of noble class' living house in late Kama-kura period. It was also concluded that the origin of "Ko-go-sho" might be "Ko-shin-den", sub-ceremonial buildings in noble class' living houses in Hei-an period.

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