Two new partially saturated tricyclic ring systems, , a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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11-Amino-, a, , , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-d) and -oxepines (a-d) were synthesized by the Leuckart reaction of , a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products 4a-d and 5a-d, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and , trans(a-H, 10a-H)-trans(10a-H, 11a-H)c and c, and trans(a-H, 10a-H)-cis(10a-H, 11-H) d and d, 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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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; (1) the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, (3) the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, (4) the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, (5) The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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In the 1993 Kushiro-oki Earthquake of Richter magnitude ., simultaneous recording of earthquake motions was successfully made at the ground surface and at a depth of 77 meters in a dense saturated sand deposit. The peak horizontal acceleration was 0.47 g on the ground surface and 0.21 g at a depth of 77 meters. The acceleration record at the ground surface showed a distinctive ground response, which consisted of a cyclic motion having a period of about 1.5 seconds overlain by a spike at each peak of the motion. In order to study the mechanism of this peculiar ground response, effective stress analysis was conducted on the dense saturated sand deposit. The model used for this study was a strain space multiple mechanism model, which takes into account the effect of principal stress axis rotation. The recorded earthquake motion at a depth of 77 meters was used as the input earthquake motion for the analysis. Sampling after in-situ freezing was done in order to evaluate the properties of the sand. The results of the analysis indicated that the observed ground response was due to the effect of dilatancy of sand, which plays a significant role in the response of the dense saturated sand deposits during strong earthquake motions.

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 The stability of

‒tetrahydrocannabinol acetate (‒THC‒OAc) and ‒tetrahydrocannabinol acetate (‒THC‒OAc) in -liquid during storage was investigated. ‒THC‒OAc liquids in cartridges were stored at 80℃ or 30℃ for 28 days. The relative concentrations of cannabinoids in the liquids were measured by gas chromatography with flame ionization detection. ‒THC‒OAc decreased during storage at either temperature. ‒THC, a minor impurity, also decreased. ‒THC‒OAc liquid in a cartridge was stored at 80℃ for 57 days. The concentration of ‒THC‒OAc and ‒THC, a minor impurity, did not change during that time. Cannabinol acetate increased in all liquids, and unknown products were also detected by gas chromatography/mass spectrometry (GC/MS). The ‒THC‒OAc and ‒THC‒OAc liquids were subjected to GC/MS to detect representative diluents, glycerol, propylene glycol, and polyethylene glycol 400, but none of these were detected.

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Stereoselective synthesis of the 4, 5-syn, 5, -anti adducts (14 and 16) on the aldol condensation of the Z (O)-lithium enolate, derived from the -enone (2), to α-alkoxy aldehydes (12 and 13) was proved via the successive intramolecular Diels-Alder reaction.

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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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In this paper, centrifuge shaking table tests were conducted in order to understand the performance of seawalls during a seismic event. The model tests showed that the displacement of the caisson was much affected by the seaward shear deformation of the sand seabed beneath it during shaking. It was also confirmed that an armored embankment played an important role in the displacement of the caisson during shaking. Based on these test results, a two-dimensional DEM-FEM coupled analysis method was newly developed to numerically predict the deformation of seawalls covered with armored embankments during earthquakes. The movements of the armor units were calculated by DE analysis and deformations of the caisson, rubble mound, sand seabed and backfill were calculated by FE analysis considering the non-linearity of the soil materials based on the effective stress. Dynamic interaction was taken into account by delivering the nodal displacements of the finite elements or the nodal forces converted from the contact forces through the imaginary distinct elements defined at the boundaries between the DE and FE domain. The applicability of this method to the prediction of the deformation of seawalls was verified through numerical simulations of the centrifuge model test.

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Seismic records obtained from a seismometer array located in downtown Tokyo Japan for about ten years were inversely analyzed to estimate the dynamic soil parameters. Due to the illposed nature of the problem, the simple and often used "least square method" does not properly estimate the parameters. The Extended Bayesian Method combined with the Akaike Bayesian Information Criterion was introduced to overcome this difficulty. The results obtained were compared with dynamic triaxial test results obtained at the time of the seismometer installation. The shear moduli agree quite well with the estimated results, however the damping ratios estimated are slightly higher than the ones obtained in the laboratory.

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This paper concerns the stability against overturning of the caissons on rubble mound subjected to wave loading. A theoretical discussion is first made of the stability of a leaning caisson during wave loading, as a single degree-of-freedom system. The expression for the lower bound of driving moments sufficient to overturn a given caisson is derived. A review is then made of the damages induced to a composite breakwater, which consisted of two adjoining Stretches and C with slightly different sizes of caissons. Attention is called for the observation that most of the caissons in Stretch were overturned, whereas no caissons in Stretch C were brought into overturning. This fact is examined in detail in the light of the theory of overturning, making it possible to estimate the destructive wave heights that are compatible with the observed patterns of damage in Stretches and C of the composite breakwater.

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Stress wave theory is applied to open-ended pipe piles to clarify the effects of soil plug on the behaviour of piles during driving and static loading. Measured field data and various numerical models are reviewed ; methods are presented to calculate wave propagation in both the pile and the soil plug ; modelling is presented which takes into account the interaction between the soil plug and the pile ; also presented is simplified method to estimate the loadsettlement relation of the pipe pile in static loading. By correlating observed and calculated values in two analytical cases, the authors demonstrate that incorporation of the soil plug (modelled as a series of masses and springs) is required to correctly predict pile behaviour during driving and static loading.

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Based on the methods previously presented by the authors (Yasuhara et al., 1992, 1994, 1996) for predicting the degradation in strength and stiffness of soft clays in the course of cyclic loading, a methodology has been developed to estimate the cyclic loading-induced settlements. The method also includes not only immediate settlements but also post-cyclic long-term settlements due to dissipation of cyclically induced excess pore pressures in soft soils. The simplified formulae included in the proposed methodology are given as functions of the amplitude of cyclic-induced excess pore pressure normalized by the confining pressure, u/p'_c, plasticity index I_p and factor of safety against bearing capacity failure, F_s. The calculations of cyclic-induced settlements were conducted for soft soil deposits with different index and geotechnical properties. The results calculated using the proposed methodology are presented in the form of a design chart to give the settlement versus normalized excess pore pressure ratio relations including the effects of the plasticity index and safety factor for bearing capacity. An example of the calculated results using the proposed procedure for the earthquake-induced settlements of embankments founded on soft clay, is presented to demonstrate the practicality of the method for design at fields.

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Shaking table tests were performed to clarify the settlement in liquefied loose sand of a new foundation incorporating top-shaped concrete blocks. In the tests, blocks of half scale were installed as they are in practice, by using a crusher-run, a lattice of iron rods and iron bars. Shaking table tests were also conducted on foundations with two differently shaped concrete blocks to investigate the effectiveness of the three foundations in reducing settlement. One was a T-shaped concrete block, or a disk-shaped concrete plate with a leg. The other was a conical concrete block without a leg. The results of shaking table tests showed that the foundation with the top-shaped concrete blocks was most effective in reducing the settlement among the three types of foundation. FEM elastic analyses were performed to compute the stress distributions in the models and in-situ ground when the top-shaped concrete blocks were applied and to confirm whether liquefaction resistance of the sand layer below the foundation is large. Moreover, the factor of safety against liquefaction, F_L was evaluated in in-situ model ground, in order to compare with sensitivities against liquefaction in the ground without countermeasures and with top-shaped concrete blocks. For the liquefaction analyses, shear stress in the ground during an earthquake was estimated by dynamic analyses using the SHAKE computer program.

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The original Drnevich Resonant Column apparatus has been designed for testing cylindrical soil specimen with maximum longitudinal and torsional stiffnesses corresponding to approximate resonant frequencies 285 Hz and 318 Hz respectively. This apparatus has been modified successfully and its stiffness has been increased to over threefold in the longitudinal vibratory mode and at least twofold in the torsional vibratory mode. Monterey No. O sand samples prepared at approximate relative densities 43% and 60% were tested with the original and the modified apparatus in the range of effective confining pressures from 49 kPa to 588 kPa. Measurement of dynamic moduli values measured with the original apparatus were up to 23% higher, and damping values up to five times higher than those measured by the modified apparatus.

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Field data indicate that the P-wave velocity in sand or gravel is sometimes much lower than that of water, even if the soil is below the water table. It is well understood that a slight decrease in saturation normally evaluated by the -value has a significant effect on undrained shear behavior like liquefaction of saturated soil. In the first part of this research, theoretical formulations of the -value, P-wave velocity and Poisson's ratio are made by taking into account the decrease in bulk modulus of water due to a mixture of air bubbles. Then, computations are carried out using formulas based on the soil properties of a typical sand or gravelly soils and Masa soil from the Kobe area to make charts correlating the variables. These charts indicate that a small decrement in the -value in the interval of =1.0 to 0. will considerably decrease the P-wave velocity. Thus, the P-wave velocity which is easily measured in the field can serve as a convenient index to quantitatively evaluate the insitu soil -value.

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Among the rivers damaged by the earthquake, two most severely damaged along the Yodo-gawa River are described. In the left levee, the settlement exceeded 2 m for a length of 1.4 km, with a maximum settlement of 3 m. Sand boils were observed extensively on the ground surface near the damaged dikes. Holocene sandy soil with an SPT N-value of 10 or less existed in the upper part of the subsoil profile. These facts indicate that liquefaction of the soil was the major cause of the embankment damage. The cyclic stress ratio required to cause liquefaction was 0.30 as determined from cyclic triaxial tests on undisturbed samples.

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 We examined the stability of

-tetrahydrocannabinol acetate (-THC-OAc) and -tetrahydrocannabinol acetate (-THC-OAc) in -liquid products. Eight samples were heated at 30℃ for 28 days and one of them was heated at 70℃ for 2, 4, , 10, and 15 days. Residual ratios of -THC-OAc and -THC-OAc were evaluated by gas chromatography with flame ion detection and their degradation products were examined by gas chromatography/mass spectrometry (GC/MS). Some samples were tested for solubility in hexane and were submitted to GC/MS analysis to detect propylene glycol and glycerol. After a 28-day incubation at 30℃, -THC-OAc was slightly decomposed (residual ratio: 84.5–94.2%) but -THC-OAc was almost stable (residual ratio: 95.2–108.%). Heating at 70℃ decomposed not only -THC-OAc but also -THC-OAc. The decomposition proceeded rapidly in the initial 2 days then slowly until 15 days later. The degradation products, four putative one-oxygen-atom adducts and cannabinol, were detected but deacetylated products (-tetrahydrocannabinol and -tetrahydrocannabinol) were not detected. All the samples tested were completely dissolved in hexane differently from propylene glycol and glycerol. Propylene glycol and glycerol were not detected from the samples completely dissolved in hexane. This study indicated that deacetylation of -THC-OAc and -THC-OAc did not proceed when the sample did not contain propylene glycol and glycerol.

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An analytical model is presented for steady-state lateral response of earthfill and rockfill dams in canyons subjected to a steady train of harmonic SH waves incident at an arbitrary angle θ. The dam is idealized as a 2-dimensional shear beam with a triangular cross-section, while the canyon is considered rectangular and consisting of elastic rock. A parametric study is undertaken to investigate the influence on the steady-state response of (a) the angle of incidence θ of the incoming waves, () the impedance ratio and (c) the canyon narrowness. It is shown that the acceleration amplification is considerably less for a dam built in flexible canyon than for a dam in a rigid canyon and, hence, the effect of radiation damping may be very important. For obliquely incident waves travelling from the left to the right, the response of the dam depends mainly on the interference of the waves transmitted through the base and the left boundary, leading to a maximum response at a θ about 30°-35°. For very long dams subjected to high frequency obliquely incident waves, it is found that there is no amplification of the motion by the dam. For low-frequency excitation, the response of the dam shows little variation along the crest and approaches the response of the elastic half-space. The results are in agreement with published results for the response of alluvial valleys subjected to incident SH waves.

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An earthquake of magnitude . occurred in the south-east coast of El Salvador on January 13, 2001, causing widespread damage to buildings and several kinds of civil engineering structures due to ground shaking and earthquake-induced ground failures, including several large-scale landslides. This paper discusses the results of the damage investigation conducted in the area after the earthquake, with emphasis on the general features of the earthquake and its effects on the ground damage, specifically the landsliding which occurred in natural slopes and the liquefaction of soil deposits. The occurrence of liquefaction in the alluvial plain exhibited several characteristics in common with those observed in other areas of similar condition. On the other hand, the main cause of slope failures in volcanic deposits was not clearly identified, and several possible sources of slope instability were pointed out.

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