Documented Case Histories Research Articles

Newmark Analysis of Lateral Spreading Induced by Liquefaction

ABSTRACT Newmark analyses of lateral spreading induced by liquefaction were conducted using a database of 22 documented case histories. Site stratigraphy and SPT values for the liquefiable soil were based upon the case-history documentation. The yield acceleration was estimated based on post-liquefaction residual shear strength estimated using three different correlations with SPT blow count. Representative acceleration time histories were selected from time histories recorded in the earthquake. The probabilistic analysis using a truncated normal distribution indicates that the lateral spreading displacement calculated using the Olson and Johnson correlation will be no more than twice the reported displacement with a confidence of 97%.

Finite element analysis for rockfall and debris flow mitigation works

Landslide risks arising from boulder falls and debris flows are commonly mitigated using rigid and flexible barriers. Debris–barrier interaction is a complicated process, so current design methods rely on the use of the pseudo-static force approach. In addition to physical testing, numerical simulations can be used to provide insight into the impact mechanism. This paper presents the applications of numerical models to simulate rigid and flexible barriers subjected to rockfall and debris-flow impacts, respectively. For rigid barriers, rock-filled gabions, a recycled glass cullet, cellular glass aggregates, and ethylene-vinyl acetate (EVA) foam were assessed for their performance as cushioning materials. From the results, empirical equations were established for predicting the boulder impact forces and penetration into the cushion layer. Amongst the materials considered in this study, rock-filled gabions appear to be the most promising for use in practice. For flexible barriers, finite-element models, calibrated using documented case histories, were developed to simulate the debris–barrier interaction. The models were used to investigate the barriers’ behavior under debris impacts from both force and energy perspectives. From the results, the hydrodynamic pressure coefficient was found to be lower than the current recommended value whilst only a small amount of debris energy was transferred to the barrier.

Class A prediction of mechanised tunnelling in Rome

Contract T3 of Line C of Rome underground, currently under construction, crosses the archaeological area of the historical centre, with significant interferences with the existing monumental built environment. A fully instrumented green field control section was established at the beginning of this contract, in representative ground conditions. This paper presents a thorough Class A prediction of the passage of the tunnels through the control section, obtained using a recently developed advanced numerical procedure. The ground was modelled with a non-linear constitutive law, calibrated with all the available data from the geotechnical investigation. The main physical processes occurring around the shield, including cutter-head overcut, shield tapering and tail void grouting were modelled in detail. The numerical results agree qualitatively with the findings from well documented case histories and results from physical models. The installed instrumentation will provide an opportunity to test the ability of the adopted procedure to reproduce quantitatively the measured performance, once the tunnels will cross the control sections and the field data will become available.

Measurement, interpretation and recommended use of laboratory strength properties of fibrous peat

Peat deposits are complex natural formations encountered in many geographical areas. Peat itself is considered as a challenging geomaterial, with many aspects of its behaviour seemingly remaining enigmas. This state-of-the-art review paper provides an extensive summary of current knowledge on the strength and shear behaviour of fibrous peats. Critical assessments and interpretations of the undrained strength, effective-stress strength and at-rest earth pressure coefficient parameter values determined for fibrous peat materials using standard and advanced laboratory apparatus are presented, focusing particularly on the consolidated undrained triaxial compression and direct simple shear approaches. Based on documented case histories of embankments, dikes and natural peat slopes, guidance is given for operational shear strength assessments in peat, aimed at bearing capacity and slope stability calculations, considering both the normalised undrained strength ratio and limit equilibrium effective-stress strength approaches. In particular, the botanical origin, structural anisotropy, humification level, likely initial overconsolidated state, tensile resistance associated with the peat fibres and possible scale effect related to the test-specimen size are discussed in the context of the strength mobilised for different testing apparatus. The test methodologies and interpretations of experimental results presented for fibrous peat in this paper should be transferable to other fibrous soil and soil-like materials.

Stress paths in deep excavations under undrained conditions and its influence on deformation analysis

The objective of this study is to examine the stress state of soils during deep excavation, in relation to the determination of appropriate soil parameters for deformation analysis of a deep excavation case using the finite element method. Two well documented case histories of a deep excavation were utilized for the validation of the analysis procedure and the selection of soil stiffness parameters. Results from the Hardening Soil model showed that the out-of-plane stress has significance influences to the direction of soil effective stress path. In addition, most of the soil inside and outside excavation zone is in the elastic behavior. Even though the effective stress path of soils adjacent to the diaphragm wall have undergone yield, but the characteristics of those soils are still dominated by the elastic behavior. Hence, the unloading/reloading parameters are predominant in a deformation analysis of an excavation case. When the undrained shear strength and unloading/reloading modulus were precisely specified, even the Mohr-Coulomb model could obtain good prediction of the wall deflections. Moreover, a hypothetical case was employed to investigate the performance of the computed ground surface settlements. The result showed that the computed ground settlement from Mohr-Coulomb model was close to the result from the Hardening Soil Small model if the layer of soft soil is deep enough and a layer of small strain stiffness zone is introduced at bottom of the model geometry.

Tunnelling-induced landslides: The Val di Sambro tunnel case study

Tunnel excavation in mountainous or sloping regions can sometimes reactivate or accelerate landslide phenomena with a potential important impact on the stability of such constructions. The problem of tunnelling-induced landslides, that represents an important issue for many areas of the world, is very complex to analyse and demanding to solve. In addition, there are very few well documented case histories in literature. The paper presents the case of the Val di Sambro twin tunnels excavated in a structurally complex formation, in a geomorphological setting characterised by landslides of various areal sizes, whose depth was not well known before tunnelling. After a description of the main technical features of the tunnels, the geological setting and the geomechanical site conditions, the paper illustrates and comments the most significant outcomes of the monitoring system in the Southern zone of the tunnels, one of the areas where the major deformative phenomena occurred. The Val di Sambro tunnels represent a unique case study for the large amount of monitoring data collected before and during the tunnel excavation through an integrated system, consisting of various measure methods (inclinometers, piezometers, underground and surface topographic measurements, SAR interferometric technique). The combined use of surface, subsurface, underground and satellite data allowed analysing the characteristics of the landslide movements before the tunnel excavation and in relation to the tunnel construction.

The Polluters: The Making of Our Chemically Altered EnvironmentRossBenjaminBy AmterSteven New York. : Oxford University Press. , 2010. 223 pp. ISBN: ISBN: 978-0-19-973995-0. , $27.95.

The Polluters: The Making of Our Chemically Altered EnvironmentRossBenjaminBy AmterSteven New York. : Oxford University Press. , 2010. 223 pp. ISBN: ISBN: 978-0-19-973995-0. , $27.95.

Anaphylactic shock and acute myocardial infarction following intravenous ceftazidine

A literature search (PubMed, National Library of Medicine, USA) was done with the key words, distal aphalangia, microcephaly and short stature. It provided only two documented case histories [2, 3]. The first case described three members of a family (father and two siblings; a boy and a girl) from Spain. The clinical features they had were partial aphalangia, syndactyly with duplication of metatarsal, microcephaly, short stature and low intelligence. The condition was thought to be of autosomal dominant inheritance [2]. The second case with some of these features was in a 17-year old boy [3]. There was consanguinity of parents suggesting the possibility of an autosomal recessive inheritance. The child we have described could be the third case reported in the literature. The consanguinity of parents suggests an autosomal recessive pattern of inheritance, but the possibility of autosomal dominant inheritance due to a fresh mutation cannot be excluded.

Handling Sediments in Dutch River Management: The Planning Stage of the Maaswerken River Widening Project

Goals, Scope and Background. Faced with higher peak discharges in the foreseeable future, the Dutch government has decided to increase the discharge capacities of the Dutch Rhine and Meuse rivers. Instead of raising the dikes, river widening measures are to be undertaken, in and along the riverbed. Such measures include surface level lowering along the rivers, channel deepening, the addition of high-discharge channels and the removal of hydraulic obstacles. To cover or reduce the costs of river widening, a coupling with aggregates (sand and/or gravel) extraction has been considered. Although the rationale of this concept is basically sound, it has met with considerable resistance, especially along the southernmost stretch of the Dutch Meuse River, in the Maaswerken project area. Main Features. The Dutch river widening projects are quite unique in size and occurrence, and the number of publicly documented case histories available for the planning of such works is inevitably few. We review the planning and decision-making process for the Maaswerken project, which is in a more advanced stage than that of the corresponding project for the Rhine. Sediment handling and aggregates extraction are focused on, which are key issues to this case. Analysis and Discussion. In the study area, there is a conflict of interests between the extractive industry and the local communities. The industry faces a policy of phasing out mineral extraction; river widening presents the last significant prospects in the area. The general public, however, has come to resent mineral extraction because of its historical impacts. Aiming at a manageable process, the Maaswerken project management kept most stakeholders in a basically reactive position: the general public was kept informed and enabled to submit formal reactions to draft planning decisions. Aggregate extraction plans and extraction volumes were only discussed with the industry. Despite not being represented, the public influenced this negotiation process by expressing dissatisfaction with interim outcomes through the media and political channels. Plans had to be reconsidered, and this closed process turned out to be only seemingly efficient. Conclusions and Recommendations. The level of public concern regarding the Maaswerken project suggests that the overall level of stakeholder involvement may have been insufficient, even though it complied with pertinent environmental and planning legislation. A participation deficit seems to have mainly occurred when defining the project's preconditions: a predefined, controversial role for the extractive industry was implicit in self-financed river widening. As planning and decision making in large projects such as the Maaswerken are prone to be affected by a negative public opinion, it is recommended that social feasibility is assessed and addressed at the very outset. © 2006 ecomed publishers (Verlagsgruppe Huthig Jehle Rehm GmbH).

Near-surface,SH-wave surveys in unconsolidated, alluvial sediments

The past decade of hydrocarbon exploration has been marked by sweeping technological innovations that have greatly advanced methods for exploration and development of oil and gas reserves. An example of major importance is the use of shear waves in marine oil and gas exploration to image reflectors beneath gas chimneys. This technology grew from infancy to maturity in the 1990s, is now incorporated into commercial processing packages, and is being used with success in a number of situations. Recent SEG Annual Meetings and the Special Section of this issue of TLE have had many documented case histories about the use of converted ( P-SV ) waves. The SH -wave (another type of shear wave), however, has been of less interest to the energy industry during the past decade. Near-surface applications of SH -waves, in contrast, have received increasing attention. The present article briefly reviews shear-wave technology advances made in the energy industry over the past decade that prepared the way for the present near-surface application of SH -waves. The article concludes with a near-surface case study using combined P - and SH -wave interpretation in an unconsolidated, alluvial setting. A shear wave having particle motion in a horizontal direction is called an SH -wave. It stands in contrast to an SV -wave, for which particle motion is in the vertical plane. SH -waves travel the entire path from source to receiver as shear waves, but recorded SV -waves commonly start as P -waves at the source and are converted to SV -waves by reflection along the way. SH -waves had their energy industry heyday in the late 1980s and early 1990s after an extensive field study directed by Conoco (the Conoco Group Shoot) and supported by many oil companies (Domenico and Danbom, 1987). That study spurred interest in the imaging potential of …

Micropiles: the state of practice Part 1: Characteristics, definitions and classifications

A major study of micropiles has recently been funded by the Federal Highway Authority (FHWA) in the United States. The subject is limited to drilled and grouted, cast-in-place, reinforced piles of nominal diameter less than 300 mm. Such piles are used for direct structural underpinning, and, when installed closely spaced in groups or networks, are used for in-situ soil reinforcement. They have become increasingly popular throughout the world since their inception in Italy in 1952, and are widely used in association with urban and industrial development and redevelopment projects. In the series of five papers, the major findings of the FHWA study are presented. Part 1 in the current paper, deals with the background to the FHWA study, characteristics and definitions, classification, historical development and types of application. Part 2 summarizes design, with distinctions drawn between single piles, and groups and networks of piles. Part 3 describes construction techniques, with reference to various national practices. Part 4 discusses testing procedures, while Part 5 provides summaries of well documented case histories which illustrate the application of the principles introduced in the first four parts. As an integral feature of Parts 2, 3 and 4, the gaps in current knowledge are highlighted, as a possible guide to future research.

Comparison of the Hyperbolic and Asaoka Observational Method of Monitoring Consolidation with Vertical Drains

The use of vertical drains and surcharge to accelerate the consolidation of clayey soils is well established in soil improvement technology. For this method of soil treatment, it is important to monitor the progress of consolidation where the average degree of consolidation is usually defined as the ratio of current settlement to the ultimate settlement due to primary consolidation. An accurate estimate of the ultimate primary settlement is, therefore, required in order to determine the state of consolidation, and the appropriate time for surcharge removal when the desired degree of consolidation has been achieved. Recently, Tan (1995) proposed a new hyperbolic method to identify the 60% and the 90% consolidation stages from field settlement data due to one dimensional consolidation. Knowing the settlement at these points, it is possible to determine the ultimate primary settlement. Once sufficient data has been recorded to identify the linear portion of the hyperbolic plot between the 60% to 90% consolidation stages, the method can be employed. This method has been validated by application to various well documented case histories in the published literature. In Japan, however, Asaoka’s method for estimating ultimate primary settlement from field observation has been widely used and is well accepted by the geotechnical engineering community. This research paper presents a comparison of two different observational methods for monitoring the progress of consolidation to determine their similarity and differences, and their accuracy of predictions compared to actual observations. First, the theoretical basis of the two methods are examined. It was found that settlement data beyond the 60% consolidation stage are needed in both methods to make accurate predictions of ultimate primary settlement. Next, both methods are applied to oedometer laboratory consolidation data for kaolin specimens in order to determine how prediction of ultimate primary settlement and coefficient of consolidation would compare in carefully controlled laboratory experiments. Finally, both methods are applied to several well documented case histories of vertical drain projects, and the predictions of ultimate primary settlement and in situ coefficient of consolidation are compared. It was found that both methods gave good agreement with predictions, making them complementary tools for use in monitoring consolidation in field applications.

Research ethics--a brief historical review to 1965.

Most discussions on modern research ethics--particularly the formation of research ethics committees (institutional review boards)--focus on the revelations of the dreadful practices in the Nazi concentration camps at the Nuremberg trial after the second world war, with the subsequent production of the Nuremberg and Helsinki Codes. In fact, however, these trials were not pivotal: there was a long history of such concerns, going back at least to the 1830s, when William Beaumont introduced a contract with his patient Alexis St Martin, as well as the later part of the century when the celebrated leprosy worker Hansen was prosecuted in Bergen for having experimented on a patient without her consent, losing his post as a result. Probably, had it not been for the entry of the USA into the First World War, public indignation at the growing number of reports of unethical experimentation in public hospitals would have resulted in regulations, while official codes were introduced in Prussia at the turn of the century and in Berlin again in 1931. Nevertheless, the impetus for modern developments came principally from the furore aroused by the proselytising of two physicians: Henry Beecher, an anesthesiologist at Harvard, and Maurice Pappworth in London, whose respective books Experimentation in Man and Human Guinea Pigs, documented case histories of egregiously less than ethical research practices that went largely unquestioned by other clinical research workers. Here I shall discuss the reactions to and influence of some of these episodes, as well as more recent developments.

Anna and the Wolf-Man: Rewriting Freud's Case History

THE WOLF-MAN B Y THE WOLF-MAN is a remarkable book promising narrative coherence while enacting its opposite: a life history shot through with indeterminacy and contradiction. Edited by Muriel Gardiner, volume consists of disparate texts dating 1919 to 1970 by five different authors, all devoted to interpreting life of Sigmund Freud's most celebrated patient. founding text is Freud's From History of an Infantile Neurosis (1914), based on his analysis (1910-14) of a young Russian aristocrat of immense wealth, Sergius Constantinovich Pankejeff. James Strachey termed it the most elaborate and no doubt most important of all Freud's case histories.' book includes an account of a second analysis conducted by Ruth Mack Brunswick, to whom Freud referred Wolf-Man in 1926 in consequence of his suffering from a hypochondriacal idgefixe concerning a scar on his nose (264). Gardiner, herself a psychoanalyst who trained under Brunswick, recounts her long friendship (1935-70) with this special patient who remained throughout his life a ward of psychoanalysis.2 A foreword by Anna Freud cites need for complete and adequately documented case histories and endorses book as the unique opportunity to see an analytic patient's inner as well as outer life unfold before our eyes (ix, xii). These authoritative texts provide setting for Wolf-Man's memoirs, written sporadically over nineteen years toward end of a long life. A selection of photographs Pankejeff family papers serve as illustrations. One double portrait, captioned The Wolf-Man and his sister, Anna, about 1894, at ages of seven and nine shows two children indissolubly linked (fig. 1). older, taller sister stands while her brother sits on a raised support so that their bodies occupy same plane, joined together at head and torso like Siamese twins. Anna's right hand protectively encloses her brother's left, while her left arm encircles him. Elegantly clothed in embroidered dress and sailor suit respectively, their solemn self-presentation mirrors ritual formality of photographic pose. Their introspective gazes convey a sense of sibling solidarity reinforced by conventions of late-nineteenth-century studio portraiture.3

Validation of Hyperbolic Method for Settlement in Clays with Vertical Drains

In this paper, the hyperbolic fitting method is extended to the case of consolidation with combined vertical and radial flow, which occurs when vertical drains are used to accelerate consolidation in clayey soils. Theoretical results indicate that the hyperbolic plots are linear between the U 60 and U 90 points for the combined flow problem. Based on detailed parametric studies, it is shown that the slope ( α ) of the first linear segments between U 60 and U 90 for the theoretical hyperbolic plots (T v / U vs T v ) depends only on three non-dimensional parameters. These are the drain spacing ratio ( n ), the drainage path ratio (H/D), and the consolidation coefficient ratio ( c h / c v ) . The slope S i , of the first linear segment of the field hyperbolic plot and the slope α can be used to identify the U 60 and U 90 points on the field settlement plot. These are used to estimate the total primary settlement from field settlement data as either α /S i , δ 60 /0.6 or δ 90 /0.9. In order to validate this approach for estimating total primary settlement for consolidation of clays with vertical drains, a controlled laboratory experiment using a flexible fibre drain in a clay cylinder, and several well documented case histories were examined. Estimates using the proposed hyperbolic method agree very well with actual settlements, thus, validating the method for field applications.

Liquefaction during the 1990 Manjil, Iran, earthquake, I: Case history data

Abstract During the 1990 Manjil, Iran, earthquake (MS = 7.7), an estimated 35,000 people lost their lives and more than 300,000 were left homeless. The earthquake ground shaking caused enormous destruction of unreinforced structures. In addition, widespread liquefaction contributed significantly to building damage in towns as far away as 85 km from the ruptured fault. Following the earthquake, the authors surveyed the liquefaction regions, conducted geotechnical field explorations, and documented case histories on liquefaction of level ground, liquefaction-induced building settlement, permanent ground displacement, and performance of piles and piers in liquefied soils. This article presents and discusses the data of the case histories investigated. In addition, based on the evidence from the Manjil earthquake, the importance of geologic input in mapping of liquefaction potential in earthquake-prone regions is demonstrated. In the companion article, the authors present the results of their analyses of liquefaction-related case histories.

Earthquake recurrence and risk assessment in circum-Pacific seismic gaps

THE development of the concept of seismic gaps, regions of low earthquake activity where large events are expected, has been one of the notable achievements of seismology and plate tectonics. Its application to long-term earthquake hazard assessment continues to be an active field of seismological research. Here I have surveyed well documented case histories of repeated rupture of the same segment of circum-Pacific plate boundary and characterized their general features. I find that variability in fault slip and spatial extent of great earthquakes rupturing the same plate boundary segment is typical rather than exceptional but sequences of major events fill identified seismic gaps with remarkable order. Earthquakes are concentrated late in the seismic cycle and occur with increasing size and magnitude. Furthermore, earthquake rup-ture starts near zones of concentrated moment release, suggesting that high-slip regions control the timing of recurrent events. The absence of major earthquakes early in the seismic cycle indicates a more complex behaviour for lower-slip regions, which may explain the observed cycle-to-cycle diversity of gap-filling sequences.

Use of Well Test Results in Oilfield Development Planning in the Timor Sea

Summary The analysis of several transient-pressure surveys employing both analytical and numerical simulation techniques is presented. Case histories include examples of the following: partial penetration and spherical flow; flow influenced by various boundary conditions and geometries, including linear flow; variations in transmissibility; and effects from ocean tides. It is shown how these well-test results can be integrated with the geological framework, and their overall impact on oilfield development planning is discussed. Introduction The success of defining an optimum hydrocarbon-field development plan is crucially dependent on the early knowledge of the reservoir drive mechanisms and heterogeneities that may affect fluid flow in the reservoir. For offshore field developments, decisions related to the possible placement of injectors are of particular concern. As shown in the documented case histories, a greater effort to obtain quality data from extensive well testing may be warranted in such situations to confirm the geological model derived from seismic. petrophysical, and geological considerations. In any development, but particularly of significance in offshore (platform) situations, the three largest reservoir uncertainties commonly found are related to aquifer strength, sealing capacity of faults, and the extent of sand development. This is also true of the situations described here that use floating production facilities kept on location by a single-point mooring system, accommodating a small number of wells. In these more marginal field situations. there is not only a need for technically creative and novel engineering solutions that are robust and cost-effective, but also a need for a more detailed definition of future production and injection expectations and strategies. Well Testing In Timor Sea Oil Fields One new frontier in oilfield development is the Timor Sea. This offshore area, bordering the northwestern coast of Australia (see Fig. 1), has been explored to a relatively small extent, and to date only two commercial fields have been delineated: the Jabiru and Challis fields, contained in Permit AC/P4. In the Jabiru field, further described in later sections, it could be ascertained from well-test analysis that the large degree of reservoir faulting would not impede the initially indicated high production rates. A second vital piece of information obtained from well tests in this field relates to the anticipated aquifer response. In this respect, an effective vertical-to-horizontal-permeability ratio could be deduced from partial penetration and hemispherical flow. Although the well tests conducted were not strictly limit tests, they nevertheless indicated the accessibility of large reservoir volumes and the likelihood of a strong bottomwater drive. In contrast to the Jabiru field, which shows a sand development of considerable thickness, the Challis field comprises relatively thin oil-bearing sands. This field, also further described in the following sections, presented a particular challenge for well-test analysis. Because of the limited sand thickness, the impact of faults led to varied pressure-transient characteristics arising from different flow and boundary conditions. Furthermore, because appraisal wells in this field are to contribute directly to future production (subsea wells), the determination of "connected oil" is of great importance, particularly because completion costs, including costly flowlines, exceed the original drilling cost. The confirmation of reasonably sized fault compartments is also a prerequisite for the successful placement of water injectors. In the Timor Sea fields discovered so far, permeabilities are in the darcy range, requiring certain precautions to be taken during testing i.e., the use of high-accuracy gauges and tide corrections. As previously observed in Australian offshore sedimentary basins, corrections for ocean tide effects are particularly necessary, because these perturbations can be easily misinterpreted as boundary effects when superimposed on a relatively flat pressure-buildup response.

Infants with AIDS: Implications for development

It is well known that HIV‐infected women of child bearing ages are reported to be at substantive risk of transmission of AIDS. A complex illness with devastating consequences, AIDS affects an infant's interactions with the physical and social environment. As such, physiological and neurological impairments associated with AIDS prevent and increase the difficulty of optimal developmental progression. With the increasing numbers of infants afflicted with this disease, as well as the predictions for the rest of the adult population, the associated emotional and social ramifications need to be addressed by the health community. To illustrate the impact of AIDS on developmental processes, excerpts from three documented case histories are presented to highlight physical, socio‐emotional, and cognitive impairment.

Seismic Stability of Gentle Infinite Slopes

Deterministic and probabilistic analyses of the stability of gentle infinite slopes subject to seismically induced excess pore pressures and inertia forces are developed. In the deterministic analysis, classical equations for infinite slope stability are rewritten to explicitly include excess pore pressure and seismic acceleration. Equations for the factor of safety are developed that include these factors. In the probabilistic analysis, the seismic acceleration, excess pore pressure, and effective friction angle are considered random variables. Acceleration peaks are considered Rayleigh distributed. Excess pore pressure is predicted using a model that considers Rayleigh distributed shear stress peaks. The friction angle is modeled with a Beta distribution. Acceleration and pore pressure development within the gentle infinite slope are assumed the same as those in a horizontal deposit of the same average thicknesss. Finite element analyses are performed to investigate the limits of this assumption. Results from both analyses are compared to documented case histories of lateral spreading.