This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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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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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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Two new partially saturated tricyclic ring systems, , a, 7, , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (a and ) were synthesized. Compounds a and were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated a and (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), a (trans) and (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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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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Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA2 programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.

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An empirical equation in use for estimating the pseudo-elastic shear modulus, G_f, of subsoil, associated with shear strains less than .001% is proposed in this paper. In a series of in-situ seismic cone tests performed nationwide, the profiles of both G_f and the in-situ void ratio, , with depth were successfully characterised at five sites, each comprising a soft clay layer deposited in the Holocene era. The database which comprised the original data from the field and laboratory tests, coupled with similar information on well-documented Holocene clay deposits in Europe, was statistically analyzed in attempts to determine a generalised relationship with which G_f of soft clay may be reasonably estimated only from routinely available borehole data; that is and the current geostatic effective overburden pressure, σ'_v. An empirical relationship, G_f=, 000 -√(σ'_v) (kPa), was derived from the statistical analysis applied to data from seven different clays worldwide, for which extended over a range between 1 and , and the overconsolidation ratio ranged roughly between 1 and 2. The applicability of the proposed relationship was evaluated for two case records, each in which the clay exhibited unusual behavior; i.., the undrained shear strength remained more or less constant with depth due to the existence of artesian pressure at one site, and, at the other, G_f decreased, whereas increased, with depth. It was demonstrated that even in these clay deposits exhibiting exceptional profiles, the proposed relationship was capable of predicting G_f with a reasonable accuracy by determining the profiles of and σ'_v with depth. In addition, the prediction when compared to G_max from carefully performed laboratory cyclic tests, yielded a better estimate of G_f from the in-situ seismic survey. Despite the fact that the empirical relationship was initially designated to estimate G_f of soft clays, it may be equally applicable to sandy deposits. This was verified by comparing it to similar, and well-established, relationships developed for sands. A case record as such is also described for a loose sand deposit at Higashi-Ohgishima in Tokyo Bay which was placed in 1960's by land reclamation.

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A sample of [³H] tobrarnycin (, 000 Ci/Mole) has been synthetized and incubated with
the bacterial ribosome and its subunits. The results obtained show that this antibiotic has
two types of binding sites. The primary one is probably responsible for the inhibition of
protein synthesis whereas the secondary one is probably related to the misreading and reading
tiirough of the messenger RNA.

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The paper presents results from an extensive experimental model study of response of dry sand to impact of a rigid tamper. In the laboratory tests a circular steel tamper was repeatedly dropped on sand contained in a large tank. Measurements included tamper acceleration aud soil pressure at impact, tamper settlement, aud soil densities and strains. Effects of tamper drop height, weight and contact area were investigated. A method is presented for the evaluation of global dynamic stiffness of the soil mass affected by the impact by calculating a dynamic settlement modulus (DSM). The DSM values are determined from integration of the impact acceleration record with respect to time using measured integration constants. DSM values show good correlation to soil densities and corresponding elastic moduli obtained from laboratory tests for loose sand. However, for dense sand, results indicate apparent discrepancies between elastic modulus and the higher DSM values. Analyses of normalized impact energy and the resulting densification in the sand in terms of normalized dimensions of volumetric strain (relative density) contours show unique correlations which are used for a proposed rational design method for dynamic compaction in dry sandy soils.

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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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11-Amino-, a, 7, , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-) and -oxepines (7a-) were synthesized by the Leuckart reaction of , a, 7, , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products a- and a-, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and 7a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and 7, trans(a-H, 10a-H)-trans(10a-H, 11a-H) and 7, and trans(a-H, 10a-H)-cis(10a-H, 11-H) and 7, were isolated and their configurations and conformations were elucidated by chemical methods together with ¹H-nuclear magnetic resonance spectroscopic and X-ray crystallographic analyses.

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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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In this study the field feasibility of an innovative thermal technique to improve the performance of prefabricated vertical drains (PVD) used in conjunction with the preloading ground improvement method is investigated. For this purpose, two identical . m high full-scale test embankments for preloading were constructed over the soft Bangkok clay where a conventional PVD system was installed underneath one embankment and a novel prefabricated vertical thermo-drain (PVTD) system was utilized for the other. The PVTD unit consists of a U-tube made of cross-linked polyethylene plastic (PEX) that is attached to a conventional PVD unit. Preheated water at about 90° is circulated through the attached U-tube to raise the soil temperature underneath the PVTD embankment. The behavior of the two test embankments were compared in terms of excess pore water pressure and consolidation results. The comparison shows the advantage of a PVTD system over a conventional PVD system. The rate of consolidation increases significantly in the PVTD system due to the temperature effect on the hydraulic conductivity. Moreover, the embankment with the PVTD system generates more settlement due to the thermally induced irreversible contraction of saturated normally consolidated soft Bangkok clay.

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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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