bluuebunny/crossref_metadata_2025 huggingface dataset:
Granular columns in improving stability of vulnerable slopes – search for the optima by genetic algorithms
Authors: Saha Abhijit
Published: February 2025

A mathematical model of a unit cell of a ‘granular-pinned’ slope had been analyzed (Saha 2001) to predict the increased resistance of potential sliding mass of the ‘pinned’ slope due to higher shear strength and free-draining characteristics of the ‘granular-pin’ or column. The present investigation illustrates the effectiveness of a new generation optimization procedure, the genetic algorithms (GA), to find out the minimum Factor of Safety of virgin slope vis-à-vis reinforced slope. GA does not require problem specific knowledge for carrying out the search since it is a tool guided by stochastic principles instead of gradients. The objective function to be optimized in the two cases has been taken as the factor of safety expression of Bishop's simplified method (1960) for virgin slope and Saha's (2001) expression for reinforced slope. A specific stretch of vulnerable ‘Bhagirathi-Hooghly’ river bank (-the southern part of River Ganges- the major hydrodynamic system that formed the world's largest delta) has been chosen for the analysis. The study compares the results of prediction of failure susceptibility of river bank by directed grid-search in literature (Parua, 1992) with the present random search analysis. It emerged from the study that marked improvement in stability of such slopes could be achieved by granular-pinning that results in changing the potential virgin failure surface. Both gradual drawdown (GD) and instantaneous drawdown (ID) analysis exhibited marked improvement; though improvement in ID case, that is likely to govern in tidal deltaic zones, is about thrice than that obtained in GD case.
Effect of initial static shear on cyclic behavior of sand
Authors: Yang J.  , Sze H.Y.  , Heung M.K.
Published: February 2025

Liquefaction of saturated sand deposits poses a considerable threat to the safety of various engineering structures during earthquakes. Among various factors that have been identified in the laboratory to affect the liquefaction behavior of sand, the initial static driving shear is a key one in the liquefaction analysis involving earth dams, slopes and high-rise buildings. While the cyclic behavior of sand without initial static shear has been studied extensively, a general consensus has still not yet come up regarding the initial shear effect due primarily to a lack of convergence and consistency in the limited available data, resulting in significant difficulty and uncertainty in quantifying the effect. This paper presents an experimental study of the initial shear effect on cyclic liquefaction behavior of sand, focusing mainly on very loose sand. The data base produced is able to improve the current understanding and to clarify the existing uncertainty. A new concept, termed as threshold α, is proposed along with the use of zero reversal line to better characterize the effect of initial static shear stress.
Slope stability analysis and slope failure simulation by SPH
Authors: Bui H.H.  , Sako K.  , Fukagawa R.
Published: February 2025

In this paper, the SPH method is applied to evaluate stability of a slope and to simulate the gross discontinuities after failure. Herein, the Drucker-Prager model with non-associated plastic flow rule is employed to describe the elasto-plastic soil behaviour. The shear strength reduction method is applied to estimate the safety factor of a slope, while critical slip surface is automatically determined from contour plot of accumulated plastic strain. To take into account the pore-water pressure, a new SPH momentum equation is proposed. It is shown that by using this new expression of momentum equation, the free-surface boundary condition between water and submerged soil is automatically imposed without explicitly implementing a computational procedure to calculate an external force (pressure force). This paper suggests that the new SPH momentum equation developed herein is also applicable for further developments of SPH for saturated/unsaturated soils. As an application of the proposed method, slope stability analyses and slope failure simulations of a two-side earth embankment are performed and then comparing with traditional solutions. Very good agreements with limit equilibrium method and finite element method (FEM) have been obtained. This suggests that SPH is a promising method for the current application, especially for handling large deformation and failure of a slope subjected to heavy rainfall or earthquake loading.
Stress-strain and stability analysis of tailing dam Toranica – Kriva Palanka
Authors: Dimitrievski Lj.  , Ilievski D.  , Dimitrievski D.  , Kolevski V.
Published: February 2025

This paper deals with stress-strain and stability analysis of tailing dam Toranica – Kriva Palanka for specific stages of construction. In the technological concept of the mine for lead and zinc Toranica - Kriva Palanka (north-east of Republic of Macedonia), a tailing dam for disposal of flotation barren soil which remains after the processing of the mine material had been constructed. This tailing dam exists in the past 20 years. On the upstream side there is an embankment retention dam for diversion of river Kriva Reka into drainage tunnel. The tailing dam is on the down stream side made by fine sand and silt as products of flotation process.
Numerical analysis of circular reinforced concrete tunnel lining
Authors: Siemińska-Lewandowska A.  , Mitew-Czajewska M.
Published: February 2025

The paper describes the results of a numerical analysis of reinforced concrete tunnel lining in four characteristic cross-sections, taking into account different modelling methods. The calculations were performed with the use of the finite element method and GEO5 FEM software using data from the design works related to the planned construction of the technical tunnel under the river Vistula. Owing to significant differences in momentum values, the conclusions from the study will be used to define the joints between tunnel segments and to dimension the tunnel lining in the technical design of the structure.
Construction of the Donetsk (Ukraine) Underground Railway on the undermined territories and tectonic faults
Authors: Rozenvasser G.R.  , Symonovych V.E.  , Tokovenko V.N.  , Gavrilenko Yu.N.  , Shatalov V.F.
Published: February 2025

The actual problems of the Donetsk Underground Railway construction related to geomechanics, mechanics of the underground constructions and building structures have been examined. Preconditions for developing the structural measures for running tunnels protection against uneven deformations of the soil body have been set up. The technical solutions for protection against the undermining and tectonic faults to improve the construction serviceability with minimum costs have been offered and implemented.
Long term behavior of staged construction of a dam on soft clay
Authors: Gurbuz A.  , Dincergok T.
Published: February 2025

The staged-construction of Alibey Dam on the Alibey Creek near Istanbul in Turkey started in 1968 and ended in 1983 to generate a reservoir to meet up the water requirement of Istanbul. Alibey Dam had a geotechnical challenge of a 29.5 m high zoned earth-fill dam on 33-m-thick soft alluvial foundation and occasional sand bands. Alibey Dam consists of upstream cofferdam, downstream cofferdam, main body and test embankment. Before the construction of Alibey Dam, both extensive field and laboratory tests were performed to determine the engineering parameters of foundation soils. During the construction and approximately 30 years after the construction of the dam, the behavior of the foundation soils and the embankments were monitored using extensive instrumentation placed into the foundation soils and the dam body. All available performed and measured data before the construction, during the construction and approximately 30 years after the construction are collected and presented here to shed light on the staged construction of the dam on soft clay.
Value engineering optimizes foundation design and construction in Karst terrain – A case history
Authors: Basile C.  , Saxena D.  , Saxena A.
Published: February 2025

A case history of design, prediction, instrumented static load tests, installation monitoring, and integrity testing of production piles for a power plant is presented. Vibration-free installation, site specific restraints, and owner specified production time frame justified selection of ACIP piles as the most economical and effective foundation approach. Site-specific concerns were raised about the porous nature of the fragmented and decomposed limestone strata at the site which could lead to high grout intake and interconnecting of piles during construction which could lead to increased foundation costs. A multi-phase ACIP pile evaluation program consisting of instrumented compression and tension pile load tests, single hole ultrasonic pile integrity testing, as well as full time production pile installation monitoring was specified. Implementation of this testing and evaluation program resulted in grout usage within an acceptable range and the compression load tests yielded data that allowed use of higher capacity piles than the original design. A total of four hundred (400) production piles were monitored with recorded rate of insertion/extraction of the auger, grout pump strokes and pressure, total grout volume, and grout factors as well as quality and strength of grout. Additionally, 5% of the production piles were tested for integrity and continuity using Pile Echo Method (PEM) and Single Hole Sonic Logging (SSL) test methods. This engineered, monitored, and tested program provided an affordable foundation solution that resulted in cost savings over the other foundation alternatives for the owner.
Expérimentations en vraie grandeur et sur modèles réduits du renforcement des sols par inclusions rigides
Authors: Briançon L.  , Plumelle C.  , Canou J.  , Dinh A.Q.  , Dupla J.C.  , Baudouin G.  , Thorel L.  , Rault G.
Published: February 2025

Le renforcement des sols par inclusions rigides est une technique intéressante qui apporte une solution efficace en termes de réduction de tassement, de temps de construction et de coût. La combinaison d'inclusions verticales rigides et d'une plateforme granulaire améliore le transfert de charge de l'ouvrage vers le substratum. Le projet national français A.S.I.RI. a été initié pour améliorer les connaissances dans ce domaine et proposer des règles de mise en œuvre et de dimensionnement. Dans le cadre de ce projet, des modélisations physiques, numériques et des expérimentations en vraie grandeur ont été réalisées. Cette communication présente les différentes approches expérimentales mises en œuvre pour mieux cerner les divers aspects du fonctionnement de ces renforcements par inclusions verticales.
Comportement d'un ouvrage de soutènement en sol renforcé soumis à des sollicitations de type ferroviaire
Authors: Soyez L.  , Le Kouby A.  , Mestat P.  , Hosseingholian M.  , Campion G.
Published: February 2025

Réseau Ferré de France (RFF) et la Société Nationale des Chemins de Fer Français (SNCF), associés au Laboratoire Central des Ponts et Chaussées (LCPC), souhaitent mieux comprendre le comportement des soutènements en sol renforcé par armatures métalliques dans le domaine ferroviaire. Un plot expérimental, qui représente ce que pourrait être une portion de 8 m de long d'une future LGV incorporant un soutènement, a été mis en œuvre au Centre d'expérimentation Routière (CER). Il a été sollicité à des niveaux de charge de service et aux différentes fréquences rencontrées dans le domaine ferroviaire. Les mesures de contrainte et d'accélération verticale, de déplacement de l'interface sous-couche/remblai et de tractions dans les armatures montrent l'influence de la fréquence de sollicitations sur le comportement de l'ouvrage.
Combined cut and cover and New Austrian Tunnelling methods for MRT station in Bangkok sub-soils
Authors: Phienwej N.  , Surarak C.  , Cai H.  , Suwansawat S.  , Guan H.  , Balasubramaniam A.S.
Published: February 2025

Ground and wall movements in an excavation using a combined cut-and-cover method and New Australian Tunnelling Method (NATM) for an MRT station is studied by means of a 2D finite element analysis. An advanced elasto-plastic constitutive law is adopted to model the soil behaviour. Multi-stage construction of both the cut-and-cover box and NATM excavation are modelled. Ground surface settlements behind diaphragm walls induced by the cut-and-cover excavation are in good agreement with those calculated from the simplified method. Deflection of diaphragm wall on the NATM excavation side was smaller than that of the opposite side due to stress release from the tunnel excavation. However, ground surface settlements increased three times of the settlement occurring after the excavation of the cut-and-cover box.
Use of instrumented static pile load test results as a “crystal ball”
Authors: Chong Yit Wah
Published: February 2025

With today's strain gauge technology and availability of numerous published case studies on instrumented test piles via various geotechnical conferences, pile instrumentation in static load tests has become more popular in the field of foundation engineering in many countries. The common use of the instrumented pile load tests to investigate on the design parameters in relation to pile length provision is seen by engineers at large as the greatest benefit of pile instrumentation. However the benefits of the latter should not be confined to such an investigative purpose only. Refreshing a little bit more on the relationship among stress, strain and concrete modulus, a normal civil engineer would realize that the test results can also be used to help discern irregularities that may have occurred to the embedded pile body, predict future problems associated with the proposed pile design concept, and even detect unsound practice that may have intentionally or unknowingly formed part of the test. This paper discusses the key aspects of an instrumented test pile and how to make use of the test results as a “crystal ball” in identifying the problem areas and gauging the reliability of the results for pile length design review. The author is of the view that equipped with some appropriate techniques, engineers can train themselves to competently look at the instrumentation results to foresee situation that may be regularized during the course of a load test instead of waiting for the specialist tester's report after the completion of the load test.
Field application and numerical analysis of Suction Vertical Drain Method
Authors: Kim Soo Sam  , Ahn Dong Wook  , Kim Ki Nyun  , Kang Byung Yoon  , Han Sang Jae  , Kim Young Yoon
Published: February 2025

In this study, field application test for Suction Drain Method, which can improve the soft ground without surcharge loading or sealing sheet was performed to find out the construction period and improvement degree with suction pressure stage. Also, the analysis program for optimized finite elements with Suction Drain Method was developed, and compare and analyze with analysis results of commercial program and field test construction. As a result, settlement data from existed program was larger than actual field test data. On the contrary, analysis results of Suction-CAIN program were similar to field test results.
Ground energy and impact of rolling dynamic compaction – results from research test site
Authors: Avalle D.L.  , Scott B.T.  , Jaksa M.B.
Published: February 2025

As a major component of research activities at Sydney and Adelaide Universities into various aspects of rolling dynamic compaction as performed with the “square” impact roller, an experimental test site has been established. The test site is approximately 100m by 50m, and is part of a larger industrial property in Wingfield, South Australia. Geologically, the site comprises approximately 1-2m of non-engineered fill, overlying Estuarine deposits. The primary objectives of the work at the test site relate to quantifying the effects of the impact roller in terms of energy delivered to the ground and the ground response. Impact rollers with solid 4-sided modules of mass 8t and 12t are utilised. A monitoring and testing regime has been developed that includes physical measurements of energy on and below the impact module, surface settlement and sub-surface layer compression measurements. Early results from the testing programme provide a basis for understanding and developing the relationship of delivered to transmitted energy for the particular impact modules used at this site, the dissipation of energy through the ground and the effects on the various strata at depth due to module mass and number of passes (or energy input). The output from this study will form the basis for modelling ground conditions at this site and the effects of the impact rolling. The data thus generated will support further studies into numerical modelling of rolling dynamic compaction and the on-going programme of testing at other sites with different geological characteristics.
New approach to calculation of stresses and strains in compressible ground improved with vibrated gravel-sand columns and model verification
Authors: Kurka J.  , Zavoral J.
Published: February 2025

The presented analytic method deals with the calculation of stresses and strains in compressible ground improved with the group of vibrated or rammed gravel-sand columns. A basic case of rigid footing is solved through a set of 8 equations and following modifications are considered in calculation: the case of shear failure of gravel columns, the influence of vibration during installation, the case of variable replacement factor and the influence of different extent of column field dimensions beyond area of the footing. The second part of paper describes the solution of basic case of flexible footing. Selected examples of parameter studies on variable boundary conditions are shown. Results of presented method are compared with other studies and monitored examples from the practice.
Injectabilité d'un loess par des coulis de renforcement
Authors: Dupla J.-C.  , Canou J.  , Terpereau J.-M.  , Marchadier G.
Published: February 2025

Loess are particular soils, including an often loose and unstable structure, formed of aggregates and macropores, resulting from their mode of formation by wind deposit. They can be the seat of large strains of collapse when they are wetted and can, for some of them, liquefy when they are saturated. We present in this communication the results of experimental work intended to study the injectability of a loess of the North of France, in order to stabilize it compared to a possible liquefaction risk under railway loading. The injectability was carried out on in situ samples, using a specific injection device to inject various types of grouts. First, we present the prototype device and the experimental procedure used, then the results obtained from various grouts such as micro cement suspensions, silicates and nanosilices and we show the interest of this last product in terms of injectability for this specific soil.
Effects of an angle of mixing paddles on deep mixing in soft clays
Authors: Lee K.Y.  , Hwang J.H.
Published: February 2025

The deep mixing soil improvement are commenly used for soft ground improvement and foundation systems for embankments, port and harbor foundations, retaining walls, and liquefaction mitigations. The advantage of this method is that it not only improves the strength of soft ground, but is a superior method for the prevention of settlement. Quality controls of the improved soils affect of the efficiency of this method are not yet properly established. These effects vary depending on the construction environments and operating conditions of the mixing paddle. The strength and shape of the improved column are not unique and these are affected by the mechanical properties of the mixing paddles.
Integration of quality control and base improvement in auger piles
Authors: Green T.A.L.  , Parrock A.L.  , Laughton M.
Published: February 2025

Given the correct conditions, open-hole cast in-situ auger piles can be a simple, quick and inexpensive piling solution. These advantages are unfortunately diminished by uncertainties with regards to the transfer of stress from the base of the pile into the in-situ soil or rock. As newer, more powerful, auger rigs become available, it becomes economically feasible to install auger piles into ever more competent rock. To fully utilise the capacity available in this rock, a methodology is required to ensure a clean contact at the base of the pile. Recent tightening health and safety legislation has eliminated the traditional method of hand cleaning and inspecting the base prior to casting the pile. As such, alternative methods are required which will guarantee this ‘clean’ contact and still maintain the simple and economical nature of open-hole auger piles. This paper explores potential methods of improving the performance of such piles in compression, tension and shear, with specific reference to piles installed for the 2010 Soccer City Stadium. A range of integrated quality control and base improvement methods are proposed in the hope that these can further improve the value of this pile type.
Tunnel Stability Factor – A new controlling parameter for the face stability conditions of shallow tunnels in weak rock environment
Authors: Mihalis I.  , Konstantis S.  , Anagnostopoulos A.  , Vlavianos G.  , Doulis G.
Published: February 2025

The present paper justifies, on the basis of a significant number of parametric analyses, the use of Tunnel Stability Factor (TSF) in the preliminary assessment of tunnel's face stability conditions for low overburden heights in weak rocks.
The construction of Puerta de Jerez underground station in Seville
Authors: Justo J.L.  , Oteo C.  , Gómez P.  , Sanz J.I.  , Arozamena P.  , Vázquez M.  , Pérez M.T.
Published: February 2025

Puerta de Jerez underground station has been built under a two-storey underground car park. The station has three floors under the car park, and once it was completed, the car park was reconstructed on top of the station. One TBM tunnel had been bored below the car park before construction of the station and the other during construction. As a closure wall should surround the constructed tunnels, and in order to avoid damage to the parking and neighbouring buildings due to tunnel construction, jet-grouting screens were built around the station. The complex station has several diaphragm walls and pile walls. Inclinometers, topographic marks and piezometers have been placed so as to control deformations produced by the different construction operations. The construction process has been simulated using Plaxis 2D program and a Hardening Soil model. This has allowed correction of the soil parameters during construction and finding the ground loss produced by tunnel boring.
Improvement of monitoring, design and constructing of piled structures located at the base of soil slopes
Authors: Doubrovsky M.P.  , Poizner M.B.  , Meshcheriakov G.N.
Published: February 2025

In the practice of coastal and harbour construction there are a lot of piled structures (quays, shore protections, etc.) located at the base of landslide slope. In many cases to withstand landslide pressure, special landslide protection structures are used. Peculiarities of the study of complex systems “piled structure – landslide protection – soil slope”, based on long-years special instrumental geodetic investigations, are considered in the report. As a research model complex system functioning at the sea Port of Yuzhny (Ukraine) is studied. Method to analyze piled structures regarding degree of physical deterioration of their main bearing elements is presented. In order to provide stability of landslide slopes during construction the modular piling system was developed for piles static pressing-in. Pile monitoring data confirmed by Static Load Testing allows prediction of static bearing capacity of the piles, providing the quality assurance of the piled foundation and provides the procedure of interactive design.
Event tree analysis of the Åknes rock slope
Authors: Eidsvig U.  , Lacasse S.  , Nadim F.
Published: February 2025

A massive rockslide at Åknes in the Stranda municipality in western Norway would have dramatic consequences, as the tsunami triggered by the slide would endanger several communities around Storfjorden. Site investigations, offensive monitoring and a warning system for the potentially unstable rock slopes were implemented to reduce hazard and consequences. As part of hazard and risk assessment, event trees were constructed by pooling the opinion of engineers, scientists and stakeholders. The objective was to reach consensus on the hazard, vulnerability and elements at risk (consequences) associated with a rockslide and tsunami, quantify the hazard (probability of a rockslide and tsunami occurring) and the potential losses (human life and material and environmental damage). The probability of occurrence and the risk were obtained through a consolidation of all the branches of the event trees. The event tree analysis results in a map of the risk for the residents for the municipalities close to Åknes. The paper presents the event tree analysis process and some of the preliminary results achieved on the hazard associated with the failure of the Åknes rock slope.
Evaluation of dispersion of calculated seismic site responses through Round Robin Test in Korea
Authors: Park Duhee  , Kim Jin-Man  , Kim Dong-Soo  , Sun Chang-Guk  , Kim Sung-Ryul
Published: February 2025

One dimensional site response analysis is widely used in practice to estimate the seismic site amplification effects. The site response analysis involves determination of various uncertainties, which include characterization of future seismic event and dynamic soil properties. The accuracy and reliability of the site response analysis depend on how these factors are properly defined. A site response analysis round robin test has been performed in Korea to evaluate the dispersion of the calculated site responses caused by such uncertainties. To simulate the common practice, only the SPT, CPT data, and boring logs were given for three sites. Three input motions representative of the seismic hazard with a return period of 1000 years were given. The participants were then asked to choose a method of analysis and submit the calculated responses. The submitted results showed significant variation. Among the factors influencing the response, the shear wave velocity had the greatest influence on the dispersion, followed by the dynamic curves, and the type of analysis.
Training of geotechnical engineers in Albania
Authors: Bozo Luljeta
Published: February 2025

The last 10–15 years, in Albania were evidenced many dangerous phenomena's on construction practice, which are tied with geotechnical problems. The absence of the specialized institutes and the total privatization of construction sector, have done the necessary to train and specialize the civil engineers in geotechnical field. In this paper we want to present our experience for the training of the civil engineers, their profits and advantages. Also we would like to present the work that is done in the Civil Engineering Faculty for preparation of geotechnical engineers, capable of doing design of geotechnical structures, to resolve difficult geotechnical problems and to realize all kind of geotechnical works.
Measurement of the degree of saturation of ground by image analysis
Authors: Orense R.P.  , Kikkawa N.  , Yoshimoto N.
Published: February 2025

The degree of saturation of ground is conventionally measured at discrete points using transducers, soil moisture sensors, etc. In this paper, a novel method was developed to directly measure the degree of saturation of a continuous region of ground by noting the variation in colour of the ground as the amount of moisture in the soil changes. From photo images taken at various soil moisture contents, the colours of the images were converted into numerical values which were then related to known degrees of saturation. The method was validated through vertical seepage tests, where good agreements were obtained between the measured degrees of saturation by tensiometers and those estimated from the proposed method.
Tall buildings and deep foundations – Middle East challenges
Authors: Poulos Harry G.
Published: February 2025

This paper will describe a foundation design process for high-rise buildings. The process will be illustrated via its application to three high-rise building projects in Dubai, the Emirates Twin Towers, the Burj Dubai, and the Nakheel Tall Tower. The Burj Dubai is now the world's tallest building and the Nakheel Tower will become the world's tallest when completed. The foundation system for each of the towers was a piled raft, founded on deep deposits of carbonate soils and rocks. For each case, an outline will be given of the geotechnical investigations undertaken, the field and laboratory testing programs, and the design process. Of particular concern in these cases was a potential issue of low skin friction and cyclic degradation of skin friction. A numerical computer analysis that was adopted for the design process, using a limit state approach, will be described. For the Emirates project, a comprehensive program of pile load testing was undertaken and “Class A” predictions of both axial and lateral load-deflection behaviour were in fair agreement with the load test results. Despite this agreement, the overall settlements of the towers observed during construction were significantly less than those predicted. The possible reasons for the discrepancy are discussed. For the Burj Dubai, load tests were also carried out, and “Class A” predictions were made, taking account of the lessons learned from the Emirates project. The measured and predicted building settlements will be presented. For the Nakheel Tower, no performance measurements are available as it is in the early stages of foundation construction.
General Report on Technical Session 4B: Deep Excavation, Tunneling and Groundwater controlling
Authors: Wang W.D.  , Huang H.W.  , Shen S.L.  , Wang J.H.
Published: February 2025

The General Report reviews a total of 27 papers related to deep excavation, tunneling and groundwater controlling form 17th international conference on soil mechanics and geotechnical engineering. A total of 11 papers in the sub-theme of tunneling covers four subjects including ground movement and its effect on adjacent existing structures, ground treatment, hazard and risk management, and face stability. A total of 9 papers in the sub-theme of deep excavation session covers two main aspects of excavation engineering, of which one is design and construction, and the other is performance and new seepage control technology in excavation. A total of 7 papers in the sub-theme of groundwater controlling covers two aspects of groundwater, of which one is groundwater control during underground construction and the other is treatment of contaminated groundwater. In particular, some advances and research topics on safety of tunneling, deep excavations, and groundwater control during excavation in China are introduced.
Highway embankments on degrading and degraded permafrost
Authors: Alfaro M.C.  , Batenipour H.  , Graham J.  , Kurz D.R.  , Ng T.N.S.
Published: February 2025

Global warming is affecting transportation systems in northern Canada. Thawing permafrost and expanding infrastructure systems require improved designs, construction and maintenance. The paper provides information about sampling, testing, instrumentation, and numerical modelling on two instrumented sections of provincial roads in Northern Manitoba.
ADMINISTRATIVE REPORT OF TC-34 ON PREDICTION AND SIMULATION METHODS IN GEOMECHANICS
Authors: Oka F.  , Murakami A.
Published: February 2025

This note contains the information concerning the activities of TC34 on the Prediction and Simulation methods in Geomechanics in the period 2005-2009 in form of an administrative report to the secretary general of the ISSMGE.
New centrifuge modelling techniques for investigating seabed pipeline behaviour
Authors: Gaudin C.  , White D.J.
Published: February 2025

The paper outlines newly-developed centrifuge modelling techniques for simulating the dynamic laying of seabed pipelines and the near-surface properties of seabed soils, which were created in response to the increasing need to characterise this behaviour in design. Several examples in artificial and natural soils are presented, highlighting notably the remoulding behaviour and its effect on pipe embedment.
Experimental study of soil reaction when a rigid plate is submitted to a vertical load and a moment
Authors: Foncea Claudio  , Mutoli Darío
Published: February 2025

This experimental study deals and discusses the variations of the coefficient of soil reaction of a clean sand placed at different relative densities when a rigid plate is loaded vertically and then with a monotonic moment. The results show that two of the main assumptions used in foundation analysis are questioned, since the plate would not rotate around its center but around the edge less loaded and the soil presents a much higher rigidity below the edge more loaded than the soil rigidity obtained under a center load.
Design charts for single piles under lateral spreading of liquefied soil
Authors: Valsamis Alexandros  , Bouckovalas George  , Drakopoulos Emmanouil
Published: February 2025

When soil liquefaction occurs in slightly sloping ground or near free-face topographic irregularities large horizontal displacements may occur due to the lateral spreading of the liquefied ground. This kind of ground failure may cause extensive damage to pile-supported structures as witnessed in several recent earthquakes (Chi-Chi 1999, Kobe 1995, etc). A systematic analysis of the detrimental effect of lateral spreading requires a sophisticated 3-D numerical analysis. Still, there is need for preliminary estimation of the response of deep foundations based on readily available data, such as the geometric and the mechanical characteristics of the foundation and the maximum anticipated displacement at the ground surface. For this purpose, a set of over 200 parametric numerical analyses were performed, with the pseudo static P-y method, in order to analyze the basic parameters affecting the pile behavior. The results of the parametric analysis have been consequently combined into design charts for the computation of the maximum developed pile head displacement and moment.
Numerical modelling for the detection and quantification of deep-ocean methane hydrates using seismics
Authors: Wojtowitz G.  , Zervos A.  , Clayton C.R.I.
Published: February 2025

Methane gas hydrates have stimulated substantial international interest due to their potential as a future energy resource, but furthermore as a geotechnical hazard for offshore operations related to hydrocarbon recovery. In this context, the ability to quantify and detect the presence and concentration of hydrate in marine sediments and understand the effects it has on these host sediments has become increasingly important. The detection and quantification of gas hydrates and their effect on hydrate-bearing sediments has been inferred via exploratory seismic methods, which measure indirectly the bulk dynamic properties of sizeable volumes of in situ sediment. Traditionally, effective medium models are used to interpret the seismic data by employing theoretical assumptions that relate gas hydrate content within the sediment to wave velocities. Therefore, wave velocity can be used to deduce hydrate concentration levels. The modelling of methane gas hydrate-bearing sediments is relatively new and at present has been based on theories of rock physics and effective medium modelling. A variety of such models exists in the literature. Many effective medium models are not readily transferable to other settings, as they have been calibrated on and tested on specific sites. In addition, many models do not take into account the existence of heterogeneities of the host sediment, or the inhomogeneous distribution or formations of hydrate within the sediment. This paper presents a general review of the existing effective medium models, identifying typical areas for improvement. A new numerical modelling method is presented that can specifically take into account different hydrate morphologies within the host sediment thereby enhancing the existing effective medium models. Preliminary results from the numerical model are presented, portraying the impact of hydrate on the mass seismic properties of the host sediment.
An experimental study of clay based on a class of simple hypoelastic constitutive behavior
Authors: Vakili J.
Published: February 2025

The objective of this paper is to present a mathematically simple model to define the mechanical behavior of clay that can be utilized in determination of practical solutions for soil mechanics problems. Variable moduli models in the form of tangential stress-strain relationships according to the theory of hypoelsticity are used in this paper. The incremental constitutive relations are formulated directly based on the isotropic linear elastic formulation simply by replacing the elastic constants with variable tangential moduli which are functions of strain invariants. By examining an experimental stress-strain curve of a triaxial compression test, it has been demonstrated that the variable moduli, in this case, is a decreasing function of strain which starts at an initial value of E0and gradually reduces to zero at the ultimate deviator stress application. The stress-strain relationship, in this case, can be reduced to a simple hyperbolic from.
Physical modeling of slope failure during slope cutting work
Authors: Itoh K.  , Timpong S.  , Toyosawa Y.  , Tamrakar S.B.  , Suemasa N.
Published: February 2025

Full-scale slope model tests and centrifuge model tests were conducted to examine the mechanism of slope failure during slope cutting works. It was found that local slope failure was observed before complete slope failure and this mechanism was consistent with previous slope failure accidents. The horizontal and vertical movements of the slope could be measured during excavation, so it may be possible to predict slope failure from the typical slope movement in order to prevent slope failure accidents in future.
New description of stress-induced anisotropy using modified stress
Authors: Kikumoto M.  , Nakai T.  , Kyokawa H.
Published: February 2025

A simple and comprehensive method for describing the influences of the intermediate principal stress σ2and the stress histories on the deformation and the strength of soils, which assumes associated flow rule and obeys isotropic hardening rule in modified stress space, is proposed. The concept of the modified stress tij, which was proposed to describe the influence of σ2, is extended to the proposed modified stress tensor tij*to consider the fabric change of soils due to the stress histories as well as the variation of σ2. In this paper, the modified stress tij*is applied to an elastoplastic model named subloading tijmodel. The proposed model is verified by comparing the calculated results with the experimental results on sand.
Simplified phase change model for artificially frozen ground subject to water seepage
Authors: Ziegler M.  , Baier Ch.  , Aulbach B.
Published: February 2025

The behaviour of artificially frozen ground is largely dependent on its temperature-dependent thermal and hydraulic properties. The existing ratio of ice to unfrozen water has to be correctly represented for a realistic ascertainment of this behaviour and thus a forecast of the freezing time during icing work. The phase change model presented here can be used to describe the unfrozen water content and thus the freezing behaviour as a function of the temperature. Optimisation possibilities can then be investigated on this basis in the run-up to icing measures.
Behaviour of pumice sand during hydrostatic and K
Authors: Kikkawa N.  , Pender M.J.  , Orense R.P.  , Matsushita E.
Published: February 2025

In order to understand the characteristics of pumice sand, we scanned pumice particles using micro X-ray computed tomography (X-ray CT), which showed that pumice particles have not only surface voids but also internal voids. Therefore, pumice sand is lighter than quartz sands and also is crushable. In addition, from our previous research, the relative density of pumice sand can not be estimated from conventional CPT testing. Because of this unique behaviour, there is a need for more experimental study of this material to fully understand its geotechnical properties. First, we performed hydrostatic compression tests on loose pumice sand and monitored the volume change with elapsed time during loading and unloading. After these tests, the particle-size distribution (PSD) was measured. Second, in order to distinguish the differences in stress relaxation between loose and dense sand which might occur during CPT testing, Kocompression tests were performed at various displacement rates, from 0.5mm/min to 25mm/sec. The final compression was about 33% of the original length of the specimens. After compression, the maximum displacement was held constant for a specified period of time and the relaxation of the axial stress was monitored during this time. From these results, the stress relaxation of loose sand was slightly larger than that of dense sand, presumably because loose sand has more spaces for rearrangement of particles during the stress relaxation process.
Influence of base course gradation on response of granular bases under cyclic loading: a micromechanical study
Authors: Han J.  , Bhandari A.  , Parsons R.L.
Published: February 2025

Performance of unpaved granular bases relies on the shear strength and stiffness of granular particles. These two mechanical properties depend on shape, size, and gradation of the particles. This paper presents a micromechanical study on the influence of particle gradation on the response of unreinforced and geogrid-reinforced granular bases under cyclic loading. Commercial software, Particle Flow Code (PFC) 2D based on the discrete element method (DEM), was used for this purpose. Different biaxial assemblies of uniform particles and well-graded particles were sheared at low confining stresses for their stress-strain relationships and friction angles. The geogrid was simulated using one layer of bonded particles with different sizes to mimic its grid structures. Two base courses consisting of uniform particles and well-graded particles, which were subjected to a 5kN cyclic ramp load at a frequency of 0.76 Hz using a wheel, were modeled. The DEM study showed that the assembly of well-graded particles had a higher angle of internal friction than the assembly of uniform particles. Further, the addition of the geogrid reduced the deformation after each load cycle.
Gaming Against Medical Errors: Methods and Results from a Design Game on CPOE
Authors: Kanstrup Anne Marie  , Nøhr Christian
Published: February 2025

The paper presents design game as a technique for participatory design for a Computerized Decision Support System (CDSS) for minimizing medical errors. Design game is used as a technique for working with the skills of users, the complexity of the use practice and the negotiation of design here within the challenging domain of medication. The paper presents a developed design game based on game inspiration from a computer game, theoretical inspiration on electronic decision support, and empirical grounding in scenarios of medical errors. The game has been played in a two-hour workshop with six clinicians. The result is presented as a list of central themes for design of CDSS and derived design principles from these themes. These principles are currently under further exploration in follow up prototype based activities.
Archetype-Based Knowledge Management for Semantic Interoperability of Electronic Health Records
Authors: Garde Sebastian  , Chen Rong  , Leslie Heather  , Beale Thomas  , McNicoll Ian  , Heard Sam
Published: February 2025

Formal modeling of clinical content that can be made available internationally is one of the most promising pathways to semantic interoperability of health information. Drawing on the extensive experience from openEHR archetype research and implementation work, we present the latest research and development in this area to improve semantic interoperability of Electronic Health Records (EHRs) using openEHR (ISO 13606) archetypes. Archetypes as the formal definition of clinical content need to be of high technical and clinical quality. We will start with a brief introduction of the openEHR architecture followed by presentations on specific topics related to the management of a wide range of clinical knowledge artefacts. We will describe a web-based review process for archetypes that enables international involvement and ensures that released archetypes are technically and clinically correct. Tools for validation of archetypes will be presented, along with templates and compliance templates. All this in combination enables the openEHR computing platform to be the foundation for safely sharing the information clinicians need, using this information within computerized clinical guidelines, for decision support as well as migrating legacy data.
Design of a ‘Smart’ Patient Record System for Mammography Patients
Authors: Frigas Antonis  , Spyrou George  , Antaraki Argyro  , Patiraki Elisabeth  , Koufopoulos Konstantinos  , Mantas John  , Ligomenides Panos
Published: February 2025

One of the most common cancer types among women is breast cancer. Regular mammographic examinations increase the possibility for early diagnosis and treatment and significantly improve the chance of survival for patients with breast cancer. Keeping an informed and complete patient record is of great importance as the doctor needs this information for every patient examination. The proposed implementation is a patient record system that includes ‘smart’ algorithms in order to automatically use data from the patient's record to calculate well established epidemiological breast cancer models. A computer-aided diagnosis system is also used in order to analyze each mammogram and obtain a certain risk percentage concerning whether the patient has to undergo biopsy or not. The aforementioned system has been implemented to support a large set of patient data (1,178 patients) which included detailed personal patient data, medical history and examination details per date and is used in the daily clinical practice of a breast cancer diagnostic center facilitating patient record retrieval, storage and supporting the doctor's decisions.
Automatic Mapping of Clinical Documentation to SNOMED CT
Authors: Stenzhorn Holger  , Pacheco Edson José  , Nohama Percy  , Schulz Stefan
Published: February 2025

Clinical documentation needs to be fine-grained to truthfully represent the history, development, and treatment of a patient. But natural language, as the main information carrier, is characterized by many issues, like idiosyncratic terminology, spelling and grammar errors, and a lack of grammatical structure. Therefore coding systems, like ICD-10, have been introduced, but their use varies highly among physicians, and they are often used incompletely or incorrectly. The almost exponential growth of clinical data is yet another problem. We present a new methodology to process this data: Through combining several natural language processing methods we extract morphemes from clinical texts and map them onto concepts from SNOMED CT. We first performed a manual analysis of clinical texts received from a university hospital and evaluated the issues found in them. Based on this we implemented a prototypical system which incorporates both the OpenNLP and the MorphoSaurus natural language processing systems.