A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

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The advantages and disadvantages of using a back analysis of slope failures to evaluate soil shear strength are discussed. A methodology is presented herein that allows the implied level of reliability associated with soil shear strength parameters back calculated from slope failures to be estimated. A reliability approach is also used to estimate the probability of failure for a given limit equilibrium slope stability method, design factor of safety, and combination of back calculated Mohr-Coulomb shear strength parameters, c' and φ'. The methodology is illustrated using 39 landslides in the Orinda Formation in the San Francisco Bay area. The impact of additional case histories in the same geologic setting, i.., a larger data set, on the required design factor of safety for a given probability of failure is also investigated.

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The present paper aims at developing a simplified model for a stress-strain relationship at small strains up to an initial yielding of homogeneous saturated frozen sand. The modelling of elastic moduli for an ice-sand mixture as a composite geomaterial is first introduced based on previous studies, where a saturated frozen sand is treated as the icesand mixture. The applicability of modelling the elastic moduli under constant temperature is then discussed from the theoretical and experimental points of view. In addition, the hyperbolic stress-strain modelling of saturated frozen sand at small strain is presented. The effect of the volume fraction of sand, stiffness of sand inclusion and temperature changes on the elastic moduli and the stress-strain behaviour up to about 1-2% axial strain, which is defined as an upper yield stress, are investigated through the model, whose applicability is verified in comparison with the experimental data.

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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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From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (R, 7, R)--hydroxy-megastigma-4, 7-dien-3-one--O-β--glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.

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A procedure for limit equilibrium slope analysis based on a realistic consideration of the mobilized interslice shear forces is presented in this paper. This new approach ensures that solutions are kinematically admissible and the possibility of convergence problems, often associated with numerical solutions, is minimized. The proposed approach recognizes the importance of slip surface geometry in estimating interslice shear forces whether vertical or non-vertical slices are used in a limit equilibrium analysis. Illustrative examples are presented and the results shown to be reasonable. The calculated factors of safety based on the new method compare very well with values based on recognized methods of analysis. Yet the method is more direct and enables a proper visualization of the transfer of mobilized normal and shear forces through a sloping soil mass above a potential slip surface. The method also gives consistent results with non-vertical slices even if the shape of non-vertical slices is varied.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3- applications; i.., unlike other methods, its extension to 3- is straightforward.

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A method for analyzing the uncertainties involving the use of empirical relationships in design is developed. It is applied to evaluate the reliability of the relationship s_u(mobilized)=(measured), whereby the pertinent uncertainties are analyzed using extensive laboratory and field observed data. On the average, the relationship s_u(mobilized)= (measured) is unbiased and the error implicit in the relationship is about 15%. When cone values are used to infer s'_p, additional uncertainties on the mobilized undrained strength will incur resulting mainly from the calibration uncertainty between σ'_p and the cone values. Alternatively, vane tests may be performed to infer the mobilized strength using Bjerrum correction factor. Results show that uncertainty level associated with using the vane tests is smaller than that using the cone values, provided that similar scatter is observed between measured vane and cone values at a given site. However, prediction of the mobilized strength is even more accurate if direct measurements can be made on the preconsolidation pressure. The proposed probabilistic method also assesses the benefit of additional tests besides comparing the accuracy of using various soil parameters for predicting mobilized undrained strength. Such information is essential for planning cost-effective site characterization program.

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Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1), B (2), C (3), (4), (5) X(), Y (7) and Z (8) were confirmed by extensive 1 and 2 NMR spectral data and X-ray analysis. Blazeispirols A (1), B (2), C (3), (4) and (5) were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y (7) were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-5,7,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-4,7,11-triene-3,-dione by comparison of extensive 1 and 2 NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>C-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>C-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>C-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of C-4, C-5 and C-1, C-10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. 4. A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.

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It has been reported that visceral fat (VF) is an independent predictor of the incidence for coronary heart disease, and is associated with its risk factors. The independent effects of exercise or dietary modification on VF remain to be fully elucidated, especially in obese middle-aged men. The purpose of this study was to investigate effects of exercise on VF compared to dietary modification. Thirty-five obese middle-aged men participated in this study. They consisted of exercise group (n=, 51.4±11. yr, Group ) and diet group (n=13, 48.8±12.2 yr, Group ). Participants in Group followed -min exercise sessions on a regular basis 3 days per week for 12 weeks. Participants in Group attended weekly classes aimed at maintaining well-balanced 1,680 kcal/ diet for 12 weeks. Body weight decreased significantly in both groups (Group : −2. kg, Group : −5.4 kg). Visceral fat area (VFA) determined by computed tomography also decreased significantly (Group : −32.0 cm², Group : −39.4 cm²). An analysis of covariance adjusted by weight change revealed no significant group difference in VFA change. These results suggest that exercise-induced negative energy balance does not result in greater decrease in VFA as compared with dietary modification alone.

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This paper presents the results of 24 centrifuge model tests of nailed soil slopes and vertical walls, constructed out of dry Leighton buzzard sand. The walls were initially supported by fluid pressure from flexible rubber bags against the face, and excavation was modelled by gradually draining the fluid from the bags. The finished model walls were 200 mm high and were initially tested at 30 g acceleration to correspond to a prototype structure .0 m high. If failure was not obtained, the acceleration was increased progressively to a maximum of 80 g. No surcharges were applied. The main parameters varied in the tests were the wall slope, nail length, nail surface roughness, nail inclination, facing stiffness and facing roughness. Observations were made of the mechanism of failure when it occurred, of soil pressures on the facing, and of pre-failure deformations. Failure was always by pull-out rather than breakage of the nails, and a series of pull-out tests of the model nails was conducted to aid interpretation of the results. Failure surfaces were seen to have the shape of logarithmic spirals, and limit equilibrium analyses based on these surfaces agreed well with experimental observations. Prior to failure, earth pressures on the facing compared reasonably well with those calculated by Coulomb's method, except at the base of the wall. One test set out to model a full-scale trial wall, and although the construction process could not be exactly modelled in the small-scale centrifuge tests, comparisons were sufficiently good to give confidence in the model test results.

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This paper deals with the overall stability of an embankment foundation failure that lies at km 40+700 of the new Irbid-Amman Highway in Jordan. Slope stability back analysis was carried out for the slope to assess the conditions at time of failure, and estimate most representative shear strength parameters of foundation materials. Slope stability analysis was also carried out for proposed remedies. Probabilistic seismic hazard analysis was carried out for the landslide site. Peak Ground Acceleration (PGA) value of 0.2 g was estimated for design. This corresponds to a % probability of non-exceedence in a 50 year design life of the highway. Pseudo-static slope stability analysis was also carried out. The study concluded that the landslide movement occurred within the foundation colluvium material. It resulted primarily from the excessive load of the embankment and excess piezometric pressures generated within the slope. The most feasible remedial measure to stabilize the landslide area was removal of existing failed embankment down to the top of sandstone layer, and reconstruction (using imported free-drainage rockfill) of a split level embankment together with the construction of surface and subsurface drainage system. These measures were successfully implemented in the field.

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To remove some weak points of the limit equilibrium slope stability method, the authors have tried so far to develop a hybrid slope stability analysis method, in which stress and strain developed in a slope are determined by the finite element method, while the basic concept of the limit equilibrium method is adopted in the overall stability analysis. In this paper, first, the theory behind the hybrid slope stability analysis method is presented, together with the comparison of the proposed hybrid method and the conventional Bishop's method. Then, reinforcement mechanism and stability characteristics of the reinforced slope cutting are examined through numerical examples by the proposed method. Finally, practical application of the proposed method to an in-situ reinforcement slope stabilization project is presented. In consequence, the applicability and simplicity of the proposed method to the practical design works of reinforcement slope stabilization are demonstrated in success.

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The paper analyses the mechanical behaviour of a silty sand, as it was measured in laboratory tests on samples prepared with different density and moisture contents. After a description of the physical characteristics of the material, the methods used to prepare compacted and slurry-consolidated soil samples are reported, followed by a description of the apparatus and experimental procedures adopted. The compressibility characteristics were analysed by isotropic tests at ordinary stress levels (p'<1 MPa) and by oedometer tests at stress levels up to 40 MPa. The shear behaviour was investigated by means of triaxial compression tests following conventional undrained or drained paths with variable directions ; also, the initial shear stiffness was measured by resonant column tests. The basic behaviour of the slurry-consolidated silty sand appeared consistent with the theoretical framework of Critical State Soil Mechanics ; this soil could therefore be used as a reference material to which the mechanical properties of the compacted samples were compared throughout the paper. Two volumetric state loci were taken as reference curves to investigate the behaviour of the compacted material : (i) the isotropic compression line of the remoulded soil, and (ii) the critical state line, which proved to be independent of the soil preparation procedure. Whatever the preparation technique, the mechanical behaviour of the silty sand under triaxial compression was found to be stress-path dependent from the very beginning of the stress-strain curve. The net effect of the compaction could be assessed by comparing the stress-strain behaviour of dynamically compacted soil to that of remoulded material brought to comparable density through a mechanical overconsolidation process. The stress-strain behaviour of the compacted silty sand proved to be more fragile and showed lower initial stiffness than the remoulded soil. It was therefore observed that, even though the compaction may be considerably beneficial to compression behaviour, it does not necessarily optimise the stress-strain response under shear loads.

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Takadate loam and Hachinohe pumice, which are two typical volcanic soils distributed widely in the Hachinohe district of Japan, were selected for this investigation. The materials were used in laboratory compaction tests with a rammer under various methods of sample preparation and a given compactive effort. Unconfined compression tests were performed on the compacted soils. The sample preparation methods were categorized into the following four : Method-A (a process which adds moisture and reuses material), Method-B (a process which adds moisture and uses new material), Method-C (uses a drying process and reuses material) and Method- (uses a drying process and uses new material). Method- presented the most reasonable results in the laboratory for the real nature in-situ. Different sample preparations produced different curves for the relations of q_u, &isins;_f, and the moisture content. The relations for q_u, &isins;_f, and air void e_a, however, proved to be unique, irrespective of the method of sample preparation used for both types of soils. Thus, application of the air void in place of the moisture content was recommended as a reasonable parameter for quality control of the rolled fill in this district. It was also clarified that the relation of /q_u and &isins;_f could always normalize the uni-axial characteristics of the two tested materials, irrespective of the method of sample preparation or soil type.

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Chemical properties of ergosta-4, , 8(14), -tetraen-3-one (1) were investigated. Though 1 is rather stable to acids or bases, it reacts easily with two moleculres of oxygen on irradiation with UV light to give , -epidioxy-14α-hydroperoxyergosta-4, 7, -trien-3-one (2), which is transformed successively to , 7α;8α, -diepoxy-14α-hydroperoxyergosta-4, -dien-3-one (3) and 14α-hydroperoxy--hydroxyergosta-4, 7, -triene-3, -dione (4) under these reaction conditions.

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In-situ geotechnical investigations were performed in normally consolidated gravels, which had repeatedly experienced liquefaction, and in overconsolidated sands (in part naturally remolded) which liquefied extensively at the unusual depth of approximately 14 m to 16 m from the ground surface. A rather good correlation exists between the measured SPT-N values and the effective overburden pressure for the gravelly site; on the contrary, a highly scattered correlation was found at the overconsolidated site. The stratum of overconsolidated sands present at this latter site between 13.40 m and 25.45 m depth has shear wave velocity, V_s, values measured in crosshole tests (CH) slightly increasing with depth, but completely uncorrelated with SPT-N values, whatever corrective factor is adopted. In addition, the current formulae used for predicting V_s from SPT-N overestimate V_s measured in overconsolidated sands in CH tests, but strongly underestimate it in overconsolidated gravels. This confirms that V_s is sensitive overall to the type of material and not to the stress-strain history. The current cyclic stress ratio approach, which uses the results of SPT tests, would have been able to predict liquefaction at both these unusual sites; attempts to adopt the V_s measurements to evaluate liquefaction potential were not successful. A third site was also investigated.

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