This research was carried out with purpose of developing a method to estimate the ore load acting on ship structures.
The Coulomb's theory has been used to calculate the soil pressure, but that theory dose not adequate for the present purpose. In this research, it is assumed that a body of ore-pellets can be treated as a continuous medium having nonlinear stress strain relation, the material coefficients of such a medium were determined from the results of compaction tests, triaxial tests and friction tests.
Using a cylindrical test tank, the cariblations for the soil pressure cells used in the present research were performed, then the ore pressure distribution in the tank, the total pressure acting on the bottom of tank and the effects of the cylinder wall on the ore pressure were examined.
The behaviours of the ore in the tank were calculated by the finite element method with the material coefficients obtained from the above basic tests. The calculated results roughly conformed to the experimental results.

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Coulomb's theory of soil mechanics fails to give an estimate of ore pressure on longitudinal bulkheads in an ore carrier subjected to wave loads, because ore in a hold behaves as an elastic-plastic continuum in this situation, as the authors have suggested [1].
In this paper, elastic-plastic analysis is carried out on the basis of the elastic constitutive equation proposed by the authors [1] and the yield condition of Drucker and Prager [2]. In the case of ore carriers, behaviors of ore depend largely upon the rigidity of structures and external loads. Therefore, both ore and structures should be analyzed as a continuum, and it can be done with the aid of the finite element method.
A series of experiments of an ore carrier were performed by Ando [3] at the Ship Research Institute with models of scale 1/6.57, and the results are compared with the present theory ; it shows good agreement between them. Therefore, side structures in contact with ore can be calculated according to the present theory satisfactorily.

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The purposes of this paper are to describe an effective method of simulating the loading process of ore cargoes in large ore carrier, and to determine the initial stress distribution of are in a cargo hold. The experimental data on an actual ship by Hagiwara et al. are compared with the result of the present method, and they show fairly good agreement. Various loading processes and types of are hold are analyzed. From the comparison of these results, the authors come to the conclusion that the initial stress distribution of ore in an ore carrier in still water can be approximately determined by the formulation on the basis of the concept of the earth pressure at rest, which can be derived theoretically from the elastic constitutive equation for granular media proposed in the previous papers [1, 2].

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Hitherto, the Coulomb theory based on the theory of rupture surface has been adopted to estimate the ore pressure in a hold of an ore carrier. It introduces an approximate method for determining the stability of foundations, walls and slopes. As is indicated by experimental studies, this theory is inadequate for the present purpose.
Granular media compacted in a closed space show the elastic property accompanied with well-known characteristics as the dilatancy, and the elastic behaviors should be taken into consideration for the estimation of ore pressure.
Since Boussinesq, several authors have suggested constitutive equations for granular media by modifying Hooke's law. But these equations cannot be derived from elastic potentials, so that they cannot describe elastic deformations of granular media.
In this paper, the authors propose a nonlinear constitutive equation which shows the dilatancy phenomena. By choosing coefficients adequately, this equation is in comformity with the results of the triaxial compression test in a wide range. On the basis of this constitutive equation, stress distributions can be calculated easily by the finite element method. An experiment was performed with granular media in a cylindar subjected to non-uniform axial compression and the pressure distributions can be predicted approximately by the elastic theory.
For the precise determination of behaviors of ore, the elastic-plastic theory should be introduced, and the present constitutive equation may easily be applied with the aid of the Drucker-Prager theory of plasticity.

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This is a report of experiments on ore pressure using pellet. Some of the conclusions of the semi-static behavior of ore pressure are as follows :
(1) There is no evident difference in foundamental soil properties by the kind of pellet.
(2) Ore pressure distribution on ore hold is strictly governed by loading method, and some scattering of ore pressure is observed due to complex behavior.
(3) Ore pressure on longitudinal bulkhead in an ore carrier is greater than the value of the Coulomb's active earth pressure, and could be estimated rather by the value of the Jaky's rest earth pressure than by the value of the Coulomb's active earth pressure. But, it is not exactly estimated by those conventional theories by reason of the variety of coefficient of earth pressure due to ore hold depth.
(4) Ore pressure distribution of increment at rolling on longitudinal bulkhead in an ore carrier is rather uniform than triangle alongside the depth of bulkhead.
(5) Static ore pressure on flexible longitudinal bulkhead in an ore carrier varies widely with void ratio of pellet.
(6) A structure strength analysis in which the compressive spring is substituted for pellet is useful as an approximate solution. However, it will be necessary that an analysis of pellet taking into consideration dilatancy phenomenon.

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Generally, when designing the ore carrier, the Coulomb's theory of soil mechanics is used to determine the ore pressure which acts on the tank walls. However, the are pressure calculated using the Coulomb's theory is the static are pressure, and, actually, such factors as wave loads, ship motions, hull vibrations, etc., would demand due consideration. The authors, therefore, carried out some model tests to analyze the dynamic ore pressure and thereby formulated an experimental equation in order to estimate the ore pressure in more realistic manner. And, using the experimental equation thus formulated, the authors analyzed the distribution of ore pressure in the cargo tank of a 250, 000 tons deadweight ore carrier. Consequently it was found that the ore pressure acting on the longitudinal bulkhead in way of the wing-tank strut where a considerable amount of dynamic loads were exerted by wave, etc., would be 35 times greater than it was calculated using the Coulomb's theory, as a result of the static ore pressure being superposed by dynamic ore pressure due to horizontal and vertical ship motions and by pressure from the spring action of ore due to deformation of the longitudinal bulkhead.

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G-CSF産生腫瘍は，婦人科領域では比較的まれな腫瘍である．今回われわれはG-CSF産生卵巣未分化癌の1例を経験した．症例は47歳，未経妊で発熱，腹痛を主訴に救急外来を受診した．来院時の白血球数は21130/μlと高値であった．造影CTにてS状結腸癌穿孔による限局性腹膜炎の診断となり，S状結腸部分切除，小腸部分切除，子宮全摘，両側付属器切除を施行した．病理組織診断にて，卵巣未分化癌の腸管浸潤と判明した．脳性麻痺であり，追加治療が困難な状況であったため術後化学療法は施行せず，外来フォローとなった．術直後より白血球数は正常範囲内で推移したが，術後3カ月にて腹腔内再発を確認した．再発腫瘤の増大と並行して白血球数は158930/μl まで増加し続け，術後約6カ月で死亡に至った．再発時の著明な白血球数増加からG-CSF産生腫瘍を疑い，腫瘍摘出後に白血球数が減少したこと，剖検後の病理組織学的検索にて免疫染色にてG-CSF陽性であることから，G-CSF 産生腫瘍と診断した．悪性腫瘍に白血球数増加を伴う場合，G-CSF産生腫瘍を念頭におくことの必要性が示唆され，若干の文献的考察も加えて報告する．〔産婦の進歩66（1）：36-42，2014（平成26年2月）〕

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The some model tests on pressure loads induced by granular cargo were carried out. This paper describes the properties of static and dynamic pressure distributions measured on panels of the tank model. And a simplified method to estimate the pressure loads applied by granular cargo to the bottom plates and side walls of cargo holds is proposed.
The findings obtained from the present investigation are as follows :
(1) The new measuring method without soil pressure gage was useful for measuring the granular cargo pressure.
(2) The static component of granular cargo pressure acting on side walls and bottom plates of hold increases according to tightening of granular cargo, but the dynamic component of the pressure caused by vertical or horizontal acceleration decreases in tightened condition.
(3) The formulation based on the Janssen's theory which estimates both static and dynamic granular cargo pressure distributions adequately was proposed.
(4) The pressure loads estimation has been performed for the simple full-scale hold loading granular cargo, and the validity and usefulness of the proposed method have been demonstrated through the comparison with the measured value of Kuramoto's full-scale tests and the estimated value of ABS SAFEHULL method.

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Nowadays, the static ore pressure can be evaluated with the adequate accuracy by the explicit calculation formula, whereas as for the dynamic ore pressure, the exact calculation formula seems not to have been proposed yet.

The purpose of this study is to clarify not only static but also dynamic ore pressures utilizing the distinct element method (DEM) that can simulate the behavior of individual ore particles. The calculation program considering the coupling effect of the ore particle's motion and the ship hull structure's deformation utilizing DEM and the finite element method (FEM) is developed.

At first, an experiment using the scaled hold model was performed in order to examine the compaction behavior of ore under the repeated rolling motion. Secondly, the accuracy of calculation results by DEM was confirmed comparing with the ore pressure estimated from experimental results in both static and dynamic conditions. Finally, the ore pressure acting on the hold structure of actual ore bulk carrier was calculated under the condition of static and repeated rolling motion of ship utilizing the proposed calculation procedure.

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