The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.

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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s=1 and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (3) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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Some existing analytical methods which have been used in geotechnical engineering are modified to handle the shear strength reduction with time due to softening in fissured, over-consolidated clays and mudstones. These are limit equilibrium analysis of slope stability, calculation of earth pressure and calculation of stress and displacement around a tunnel. The softening effect is incorporated in these analyses using the failure criterion and the time-dependent strength parameters proposed previously by the authors. Examples are presented which emphasize the importance of appreciating the softening effect in analyses and further illustrate that the effect of shear strength reduction with time due to softening could easily be captured with existing analytical methods.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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[1] The purpose of this reserch is to make clear what type of design can give good effects to win the high readership score. At the begining I had to know what factors decide the readership score, and how to change the quality of the desing into numerical value. I have used the method of multi-dimentional analysis with the help of a computer, and got the estimation formula, with 7 kinds of factors, as follows ; A^^〜=+C+D+K++bF+cG. A^^〜=estimated values of the readership score. 1) , C, D, K : these four factors are given as category values (so we call them); each factor is classified into several categories. =week day, classified into 7 categories. C=pages of a newspaper, which are characterized by the kinds of articles, news, and the other reading matters, classified into categories. D=kinds of goods and trades of the advertizement, classified into 14 catedories. K=constants, given to each 13 surveys. 2) , , G : these factors are given as numerical values. G=area of advertizement, measured by the unit of column in the whole page length, being classified into kinds of area (2., 3., , 7, 10, 15) and 15 column means a whole page, about 2,000cm^2. , are the marks obtained in the design of advertizements. =sum of the marks obtained in each design element on the advertizement. =the marks obtained on the whole effect of the design. 3) a, , c : coefficients Using the above formula with the category values and the coefficients, we can obtain the naked design effect from the actual value A of readership score: +bF=A-(+C+D+K+cG). In this research, I used 1,829 data of readership score from 1960 to 1968, being obtained by 13 survevs, spring and autumn twice a year. The sample of size each survey was 3,541, 2,251, or 200 in the other 11 surveys. Multiple correlation coefficient between the estimated value A^^〜 and the actual value A is .951. The table 2^* shows the contribution indexes of each factor by 3 kinds of expression-(1) Range : the absolute difference between the maximum and the minimum category values, (2) Standard deviations of the category values, (3) Partial correlation coefficient : the relationship between the actual values A and each factors. *see the table 2 in the thesis in Japanese. [2] The important point was in the determination of the values of , . is the sum of the marks obtained in each design element, classified into four kinds : =_1+_2+_3+_. design elements [table] _1, _2, _3, _, these values have the grades, as , 1, 2, 3, and is given to the design that has no attractive effect or no applicable element. And obtain the marks of to grades as the sum of them. The values of have also grades, to . The principles to determine the values of , are as follows : a) The marks obtained of , must be the relative values among the each survey, and at the same time, they must have constancy within the same survey-the same elements of design must win the same marks obtained. ) They must be determined as to win the highest multiple correlation coefficient, when they are put into the estimation formula. c) They must be reasonable. In order to justify them, we must carry many researches on the actual condition. The frequency of accurence of each grade of , values, as the table -, and - in the thesis in Japanese.

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A comparative study of the static and dynamic response of a slope is carried out, using the large deformation theory of the updated Lagrangian formulation and the conventional infinitesimal theory. In the static analysis, a strength reduction method proposed by one of the authors is used to evaluate the safety factor of the slope. It is found that by the large deformation theory, the safety factor is larger than that calculated by the infinitesimal theory, and this difference becomes large along with the reduction of elastic modulus. In the dynamic analysis, it is observed that the large deformation theory gives smaller sliding displacement and larger response acceleration than the infinitesimal approach. It is concluded that in many cases the large deformation approach gives more adequate solutions.

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The performance of single pitch and multi pitch screw anchors during the application of installation torque is presented. An experimental testing program was conducted using five models of screw anchors with different geometry. The effect of the shape of the screw element, sand properties, and installation depth on the required installation torque value was examined. A theoretical model was developed from which the required installation torque value can be calculated in terms of the influencing factors. The required installation torque can be determined in terms of the ultimate uplift resistance calculated from any of the available theories. Based on the actual installation torque value measured in the field, the anticipated pullout capacity can be back calculated from the present theory. A comparison between theoretical and experimental results showed good agreement. Also, good agreement was observed when the present theoretical results were compared with the available field results reported in the literature.

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Based on the concept "intermediate soil wedge" which is dependent on mobilized frictional resistance, a new theory has been developed for evaluating the seismic earth pressures against retaining walls under any condition between the active and passive states. For this theory, the seismic earth pressure is separated into four components according to their formation. New equations are proposed to determine the distribution, resultant and point of application for each component. An equivalent seismic coefficient is introduced to take into account non-uniform seismic acceleration distribution with depth. The equations place special emphasis on dependence of the seismic earth pressure on mode and level of wall movement. The equations can be reduced to the Mononobe-Okabe equation for the limiting conditions. Their applicability was confirmed by comparing the predictions with a number of previous model test results.

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During earthquakes, saturated loose sandy soils often liquefy, causing serious damage to buildings and underground structures. Various construction methods have been employed to stabilize these soils against liquefaction. The popular methods are those which increase their density. Vibration and impact methods are commonly employed, but these often pose a problem of noise and vibration in urban areas. Results of previous experiments have shown that Quick Lime Consolidated Briquettes (QCB), a soil stabilizer made of quicklime and cement placed to form cylinders, significantly increases resistance to liquefaction by utilizing the effects of water absorption, swelling, and hardening. In the present study, shaking table tests were performed to evaluate the earthquake resistance of soil treated with QCB. Results of these test showed that the response acceleration and excess pore water pressure in QCB-treated soils were scarcely affected by the excitation of 200 Gals. The soil settlement due to shaking was about one tenth of that for the untreated soil, proving the effectiveness of QCB during earthquakes.

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A finite element model capable of taking into account nonlinear hysteretic soil behavior is presented to study earthquake induced retaining wall movement. The model also accounts for increase in lateral stresses and settlement associated with grain slip caused by cyclic loads. The predictive capability of the proposed method is verified by comparing responses given by the model with those computed by another existing finite element model and also with responses recorded at the Cambridge centrifuge facility. The study reveals that the wall displacement can be substantially affected, among other factors, by the increase in lateral stresses due to grain slip and wall-soil friction. Care should be taken when selecting a constant value of wall-soil friction angle for the entire duration of excitation since structural changes can occur in the soil adjacent to the wall.

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