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Volume 9 (1959 - 1960･･･
- Issue 2 Pages 32-
- Issue 1 Pages 1-
Volume 9, Issue 1
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Sizuo YOKOI1959 Volume 9 Issue 1 Pages 1-5
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSAn experimental fire has been made with a full-scale reinforced concrete room having such a window as its side is longer than its width. The following results have been obtained :
1) The main stream of flame and hot air current spurting from the window with such a shape as described above may rise more closely compared with the contrary case to the external wall.
2) Accordingly, the wall may be exposed to the hot air current over longer range in vertical direction, when the window has longer side than width, than in the contrary case, even if the window area and temperature of spurting gas at the window are the same in both cases.
3) It has been proved that the law of similarity on the trajectory of spurting gas from a window and on its temperature distribution along its trajectory, already obtained by the writer may also be applied to the fire in the full-scale building with such a window.
4) Plane glass-panes of 3mm in thickness, puttied to the sash, may only be cracked, when they are exposed to the hot air current spurting from the window downstairs, at 400°C, but when it is 500°C they may be broken down, which makes the fire spread easily to the upstairs. But wired-glass-panes may not be cracked by hot air current at 600°C at least.View full abstractDownload PDF (604K) -
Minoru HAMADA, Masaji IKEDA1959 Volume 9 Issue 1 Pages 6-8
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSWhen the fire breaks out in a building with many windows setting normal plain glass, especially in high storied building, the window glass will be broken and the pieces will scatter everywhere. In this case, we think these broken pieces will inflict injuries on persons.
The authors report on the scattering of window glass in fire. Two testing houses are masonry construction of light-weight concrete blocks, the both size are about 2×2×1.8m, one of houses is built on 4m height, other is built on 18m height.
Steel sash setting normal plain glass (2 or 3mm thickness) is built in the front window. The firewood is piled up to amount of 35kg/m2 in the house and set on fire. The results of scattering of broken pieces are as follows ;
1. In case of 4m height to the top of window, as the distance to ground from window is not great and the wind was breeze at testing time, so scattering area was small. The broken pieces almost fell within horizontal distance 2m from the window. Fine piece scattered to 5m range.
2. In case of 18m height to the top of window, as the distance to ground from window is great, so scattering area was wide. The broken pieces almost fell within horizontal distance 7m from window under condition of the wind velocity 3m/sec, and within 9m under 8m/sec. But fine piece scattered to 11m range under condition of the wind velocity 8m/sec.View full abstractDownload PDF (273K) -
Minoru HAMADA1959 Volume 9 Issue 1 Pages 9-14
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSEstablishment of the fire belt is a clue to the solution of the question to keep a city permanently fire-protective. When only a few fire belts may be established in a large urban area, we can not expect enough effect of decreasing fire risk of the city, but establishment of many series of fire belts leads to fire-protective city. These fire belt are greatly helpful to prevent big fire.
1. Establishment of fire belt decreases fire risk of a city —— the authors compared the expectant value of the fire risk of a city when fire belt is established and not.
2. Effect of fire belt in decreasing fire risk —— the authors calculated the fire risk in some combined conditions in city and fire belt.
3. The authors discussed the results of practical research of KUSHIRO and OBIHIRO cities with regard to decreasing the fire risk.View full abstractDownload PDF (511K) -
Matsujiro OYAMA, Jun MIYAMA, Kaoru KITA, Toshihisa USUBA, Soroku IWAMO ...1959 Volume 9 Issue 1 Pages 15-17
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSWhen the calculations on pipe line networks are performed by mean of the electric fluid flow analyzer, the delivery currents are easily adjusted to the predetermined values provided that the number of the delivery points are less than five or six.
But, when the more delivery points exist, the more time and effort are required to adjust the delivery current, until finally the adjustment itself becomes very difficult.
Thus it would be evident that a special device is desirable which enables fast adjustment of the delivery current, and as the result of research an electronic device involving groups of many pentodes are developed, and the accuracy of the device is enough for practical purposes.
Fig. 2. 1 illustrates the constant current circuit involving a pentode and Fig. 2. 2 and 2. 3 Show the characteristics of the circuit. Fig. 3. 1 is the connection diagram of the electronic delivery current regulator, and Fig. 3. 2 is the Ep, Ip characteristics of it.
Fig 3. 3 is the view of the regulator and Fig. 4 shows the connection between the analyzer and the regulator.View full abstractDownload PDF (325K) -
Hiroshi ABE, Kamoya ONUMA, Yasuo FUKUI1959 Volume 9 Issue 1 Pages 18-22
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSThe combustibility of wood-based materials was examined by Inclined Panel Test method with a Bunsen burner (Fig. 1) and the effects of fire retardants on ignition time, duration of after flaming and after-glowing, charred surface area and charred length are observed. Furthermore, the moisture absorption of the fire retardant-tréated materials were tested at 20°C and 95% R. H.
The wood-based materials used for this test are plywoods and three kinds of fiber boards. hard, semi-hard and insulation board. (Table 1)
These test specimens were treated with several commercial fire retardants and were conditioned to keep constant moisture contents (5～7%) in the thermostat maintained at 40°C and 35.5% relative humidity which were given by vapour from MgCl2 saturated solution.
The results obtained are summarized as follows : (1) the observed values of charred surface area and duration of after flaming are concerned rigidly with the characteristics of flame spread and seemed to give the significant estimate to fire resistance of wood-based materials, (2) the fire retardant-treated materials had a better fire resistance than the untreated ones, but the former absorbed more moisture.View full abstractDownload PDF (464K) -
Tomio IZUMI1959 Volume 9 Issue 1 Pages 23-26
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSIn preceding paper1), it was reported of the rates of destruction of foam by high temperature petroleums. The experiments were conducted on foams of expansion 10 and of specific surface 100cm-1 made of three commercial foam compounds and on eight petroleums.
This paper reported on the rate of destruction of foams of three different expansion and of four different dispersion by high temperature gas oil. The foams were made by a compressed air type foam generator and of a commercial keratine hydrolyzate 6% type compound which was not the same as the compounds used in preceding paper.
The experiments were conducted by the apparatus showed in Fig. 1. Degree of dispersion were expressed for the sake of convenience by the number of 30 mesh brass gauze used for dispersion.
Relation between rate of destruction of foam, expansion and dispersion were given in Fig. 3 and 4. Relation between rate of destruction of expansion 10 foam, dispersion and gas oil temperature were given in Fig. 5～8.
The following results were obtained :
(1) Rates of destruction of foam decreased exponentially with degree of dispersion in range of the used experimental condition.
(2) Rates of destruction of foams of low dispersion were nearly the same and that rates of high dispersion ones were considerably different as that rate of low expansion were very smaller than that rates of high expansion ones.
(3) Rates of destruction of foams increased exponentially with temperature of gas oil in the range of the used dispersion.View full abstractDownload PDF (406K) -
Isamu INOUE1959 Volume 9 Issue 1 Pages 27-31
Published: 1959
Released on J-STAGE: March 26, 2014
JOURNAL FREE ACCESSA most important requirement for the successful control of a mine fire is to attack it as quickly as possible. Author suggests an application of air foam that completely seals the cross section of mine entry and cuts off the ventilating air.
In this case, a problem is that how the foam behaves on a pressure of ventilating air or how the foam holds its seal to shock which occurs occasionally in a mine.
This report describes some experiment to solve the above problem. An experiment is to examine what pressure is needed to move a foam seal when static pressure is applied to the foam, and to decide what kind of foam can stand the pressure. (Fig. 1, Table 3, Fig. 4)
Secondly, an observation is made, when an explosion occurs, how to moderate its shock by a foam seal, and obtained a suitable foam. (Fig. 2, Fig. 3, Table 5～7)
Result is that a protein hydrolysed air foam stabilized with ferrous salt is suitable for our purpose, because it has a high viscosity and a solid film that spreads upon the surface of foam.View full abstractDownload PDF (428K)
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