bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulus of subgrade reaction for foundations on clay from unconfined compression tests
Authors: Barounis Nick  , Orr Trevor L.L.  , McMahon Paul H.  , Barounis Aristides
Published: February 2025

The unconfined compression strength test for soils can be used to determine the modulus of subgrade reaction kuncin the laboratory. It proves more economical and saves time compared with in situ plate loading tests. The modulus obtained from such tests is considerably lower than the modulus obtained from consolidation tests due to the absence of lateral confinement. Stress-subgrade reaction modulus graphs (σ-k) are presented which show the behavior of k during loading. Some typical kuncvalues are given and also Kc values, the slope of the σ-k curve. Design values of foundations with dimensions B and L can be calculated by using proposed methodology.
Deep excavation in soft, sensitive clay. A case study from Norway
Authors: Rønning S.  , Hovem S.G.  , Tørum E.  , Schram Simonsen A.  , Athanasiu C.
Published: February 2025

The Norwegian Public Roads Administration is planning a new main road northbound from the city of Trondheim in Norway. Multiconsult has been responsible for the geotechnical design for one parsell of the new road, a tunnel through soft sensitive clay (partly quick clay) based on cut-and-cover method. Maximum excavation depth in soft, sensitive clay is approx 20 m. The tunnel is planned through a populated area in the city.
Confortement par un remblai de Pied (Pathologie du glissement de Aach EL BAZ)
Authors: Hocine Bendadouche  , Salah Lazizi
Published: February 2025

Novembre 2000, Au lieu dit Aach El Baz, prés de Boulimat, le long de la RN°24, on a décidé d'effectuer des terrassements en grande masse pour construire deux villas en bordure de mer. Le terrain naturel a une pente assez prononcée avec un sol en place constitué d'éboulis de pente et de schistes très sensibles à l'eau. Les pluies diluviennes de décembre 2000 ont déclenché un glissement important qui menace maintenant la route nationale (RN°24). Une maison se trouvant dans la zone de glissement a été carrément basculée. En amont, les désordres correspondent à un glissement rotationnel avec un décrochement en tète de 4 m environ et des fissures ouvertes sur plusieurs dizaines de centimètres. Des bourrelets sont visibles au pied du talus.
Engineering geological role on cemetery planning – Lisbon Carnide's Cemetery Case Study
Authors: Almeida G.  , Almeida I.M.  , Silva M.C.R.  , Jeremias F.T.  , Pinto C.  , Muñoz M.
Published: February 2025

In the last quarter of the 20th century the estimation of available space for interment in Lisbon indicated a critical situation; the six municipal cemeteries were close to exhaustion and without capacity for expansion. The site of the new cemetery at Carnide was selected between three hypotheses as meeting the main prerequisites. However in the initial opinion it was already recognized that the topography was too rough and the composition of local soil and relatively high groundwater levels should be considered as less favourable conditions. The engineering geological characterization of the Carnide's cemetery site was based on a site investigation program carried out in 1983. As the groundwater level may reach the elevations of the burials, the design studies proposed to elevate the burial areas over the natural terrain. With this purpose a terrace modelling of the terrain was proposed, using selected materials to construct the burials prisms, and designed a deep drainage systems as well as surface system. The Carnide's New Cemetery was opened in 1996 and after a period of 12 years there were a total of about 10000 burials. According to a preliminary analysis of the first 5 years of activity (1996–2000) it seems that a timescale of 5 to 10 years as design criterion for corpse decomposition failed leading to studies with the aim of determining the causes and possible solutions for that problem.
Application of geotechnical models for early warning systems to mitigate threats posed by landslides
Authors: Trauner F.-X.  , Boley C.
Published: February 2025

The paper reports on the activities in the research project “Development of suitable information systems for early warning systems”, where, inter alia, mass movements due to slope failures in soils are analysed from a geotechnical point of view. Geotechnical models are applied to investigate causes and triggers of slope failures and to determine threshold values for the definition of critical events. To facilitate the analysis of slopes with the Finite-Element-Method, the users are assisted in the generation of simulation models by a GI system. Moreover, the GI systems provide a basis for the processing and visualization of computation results for the needs of early warning systems. Therewith the users are able to interpret the outcomes of the simulations and to assess the dangers emanating from investigated slopes. The concept is prototypically implemented for a segment of the slopes in the Isar valley south of Munich, Germany, to evaluate the developed techniques, regarding the applicability for and the improvement of warning systems for landslides, critically.
Integration of the Education, the Investigation and the Practice through a geotechnical case
Authors: Moreno Pecero G.
Published: February 2025

By means of the presentation of a real case of the application of the ground mechanics in stability of slopes, in rural ways, one is to the connection of the education with the investigation and the application of engineering, in this geotechnical case. In an introduction one widely justifies the necessity and convenience of using this model to train the engineers in order that, without a doubt, they respond with efficiency and effectiveness to satisfy the needs that the development of the countries of Latin America raises.
From practice to theory in geotechnical engineering
Authors: Kannan R.C.
Published: February 2025

Teaching geotechnical engineering started with experience in building theories of soil behavior. As theories were tested in the field and better instruments became available for the measurement of soil properties both in the laboratory and the field, the wealth of knowledge increased. Theory benefited practice and practice perfected theory. However, teaching soil mechanics has not deviated much from learning theories with the fresh engineer left to relearn the practical aspects over the years. This has produced a wealth of experience that has not been fed back to training the next generation of engineers. This paper calls practicing engineers to invest in teaching the next generation of geotechnical engineers.
Liquefaction resistance of thickened tailings of copper mines
Authors: Verdugo Ramon  , Santos Eloy
Published: February 2025

Projects associated with huge conventional tailings dams are still considered acceptable solutions for mine waste disposals. For example, in Chile there are in operation conventional tailings dams with a height of 150 meters and reservoirs with more than one billion tons of slimes. Nevertheless, for higher tailings dams an interesting and attractive alternative is the use of thickened tailings. Unfortunately, there are several cases of seismic failure of conventional tailings dams due to the occurrence of liquefaction, with catastrophic results. Consequently, the evaluation of the liquefaction resistance is an important issue, especially in the case of thickened tailings where almost no information is available regarding their seismic behavior. Accordingly, a comprehensive series of monotonic and cyclic triaxial tests were performed on reconstitutive samples. A wide range of confining pressure was used, from 0.1 to 3 MPa. The results show that the cyclic stress that causes 100% of pore pressure built up is not much affected by the level of confining pressure, which clearly differs from what has been observed in natural sandy soils. On the other hand, the results indicates that re-saturated thickened tailings, although increases their density during drying, they may still develop the phenomenon of liquefaction during severe earthquakes. Nevertheless, the post-liquefaction strength is rather high.
Modeling of groundwater lowering in multi-aquifers area
Authors: Samieh A.M.  , Mansour M.A.  , Hindi A.O.  , Mahmoud A.M.H.
Published: February 2025

Groundwater lowering is a necessity for underground construction works, especially in urban areas where groundwater exists. Economical design of dewatering schemes requires a thorough understanding of the different modeling tools that are capable of predicting the behavior of dewatering systems. This study presents the results of a three-dimensional (3-D) numerical analysis of in-situ pumping tests that were carried out in a multi-aquifers area. Comparison between the numerical results and the monitored responses of the carried out pumping tests are presented to exhibit the adequacy of the proposed numerical scheme. In addition, the necessity of using numerical modeling for complex site conditions was delineated through the analysis of a dewatering system of a large excavation that was required for a culvert construction in the considered multi-aquifers area where the pumping tests were carried out.
Monitoring soil stiffness gain due to lateral preloading
Authors: Biringen E.  , Fratta D.  , Edil T.B.
Published: February 2025

A physical model experiment was described to evaluate the effect of lateral loading on stiffness and strength improvement of foundation soils. In this study, a closed-ended cylindrical pile was inserted into a saturated kaolinitic soil simulating lateral loading while bender elements monitored S-wave travel times. These data were then used to create tomographic images of the S-wave velocity distribution at various radial distances from the pile as the excess pore water pressure dissipated. The increase of soil stiffness and undrained shear strength, and the reduction in water content were measured up to 6 pile radii from model pile, beyond which the soil improvement was minimal. The technique provides a fundamental base for the laboratory quantification of soft soil improvement using techniques such as expanding piles, Preload™ Pier, sand compaction piles, and driven piles.
The effect of sheet pile length on the capacity of sheet pile foundation
Authors: Punrattanasin P.  , Gasaluck W.  , Muktabhant C.  , Angsuwotai P.  , Patjanasuntorn A.
Published: February 2025

This research is to study the effect of sheet pile length on the capacity of sheet pile foundation. The sheet pile foundation is a shallow footing that is skirted by sheet piles around the periphery. From the previous study, it was indicated that sheet pile can dramatically improve the vertical, horizontal and moment capacities of the existing shallow foundation. This study was performed in the laboratory by using 1g physical modeling test. The new equipment was newly designed and developed in order to study the sheet pile foundation's behavior resting on sand under vertical loading test. The local sand in the Northeastern area was selected in this study. The ground models in the same conditions were prepared in the container tank by the pluviation. The effect of sheet pile length to the capacity of existing shallow footing can be evaluated by the results of load-settlement relationship. The reference case performed with shallow footing was also tested for comparison purpose. The results show the effectiveness of sheet pile to increase the capacity of shallow foundation. An appropriate sheet pile length was also found from this study. Pictures taken during the loading steps in cooperation with image processing technique can be used to identify the mode of failure and can be used to calculate the soil movement and displacement vector below the foundation.
Variation of soil density and earth pressure due to strip compaction
Authors: Fang Y.S.  , Chien Y.L.
Published: February 2025

This paper studies the variation of soil density and earth pressure in a soil mass due to the vibratory compaction along a strip on the surface of the cohesionless backfill. Experiments were conducted in a non-yielding model retaining wall facility and dry Ottawa sand was used as fill material. Based on the test results, it is found that surface settlement increased with the increasing number of passage of the compactor. The relationship between the surface settlement and the number of passes could be properly described by the hyperbolic model. The contours of Δσvafter the first passage of the compactor were analogous to a series of concentric circles. As the number of passes increased to 8, the depth of the compaction-induced zone increased with increasing energy input. After the first passage of the compactor, the contours of Δσhformed two regions of stress concentration below the surface. As the number of passage increased to 8, the two high-stress regions merged. The mechanism of soils after the first passage of the compactor could be properly explained by local-shear bearing capacity failure mode. The mechanism of soils after 8 passes of the compactor could be simulated by a single pile driven into a cohesionless soil.
Geotechnical characterization of calcareous soils for the foundation design of offshore production platforms
Authors: Medeiros Jr C.  , Drosemeyer A.  , Viana A.C.C.  , Muxfeldt A.S.  , Dutra A.B.  , Silveira C.A.B.  , Santos R.M.
Published: February 2025

The world's ever growing demand for oil and gas with the consequent increase in the production costs together with the Brazilian government's policy towards self-sufficiency are challenges that require innovative technological solutions and as a result more thorough geotechnical studies are also needed.
Predicting effective stress parameter of unsaturated soils in plane strain condition using neural networks
Authors: Ajdari M.  , Habibagahi G.  , Ghahramani A.
Published: February 2025

Accurate prediction of the shear strength of unsaturated soils is essential for a cost optimized design of these structures. Based on the effective stress equation proposed by Bishop (1959) for unsaturated soils, shear strength in these soils depends on the parameter χ which is a function of soil suction.
Effect of sampling disturbance on the stress strain behavior of a structured collapsible soil
Authors: Rinaldi Víctor A.  , Capdevila Julio A.
Published: February 2025

The secant Young's modulus determined at different strain level is a key issue in the geotechnical field to predict settlement of foundations. Most research works attribute to the effect of sampling disturbance as the main source of error in the measurement of the elastic modulus performed in laboratory samples. It seems that some kind of destructuration occurs when the soil is sampled in the field and thereafter trimmed for testing in laboratory. This work presents a fundamental study performed to evaluate the sampling effect of Argentinean loess. Block samples where recovered from open trenches and tested in the lab. The program includes laboratory and field measurement of shear wave velocity, and a battery of plate load and triaxial tests. The result allow us to conclude that the sampling procedure is performed correctly, and that the effect of sampling scale may produce a misinterpretation of laboratory results as the presence of local cemented aggregates increases the value of the measured wave velocity respect to the average field velocity.
Investigations on geotextile specimens exhumed from a mining tailings dams
Authors: Beirigo E.A.  , Gardoni M.G.  , Palmeira E.M.
Published: February 2025

The filtration behaviour of geotextiles has been extensively studied in the laboratory. Different conditions of loading and flow regimes have been analysed. However, little have been investigated under field conditions. Geotextile specimens exhumed from real filtration and drainage systems are important for the evaluation of the behaviour of geotextile filters. In this paper, a geotextile specimen exhumed from an iron ore tailings dam is studied in order to improve the understanding on the geotextile filtration behaviour in this type of work.
Rock Testing at Diamer Basha Dam Project
Authors: ul Haq Izhar  , Munir Khawar  , Farooq Khalid
Published: February 2025

Rock testing for a dam project on rock foundation and for deign of underground facilities is very much essential for determination of strength and other index properties of the rock. It helps in getting basic knowledge of the stress state for engineering e.g in what direction and with what magnitude is the major principal stress acting and to have a specific and formal knowledge of the boundary conditions for stress analysis conducted in the design phase of large dam. Water and Power Development Authority (WAPDA) Pakistan has planned to build Diamer Basha Dam, a 272 m high RCC dam on river Indus for which the construction work is going to start soon. The dam would have two underground cavern type powerhouses on both sides of the dam. Laboratory as well as field tests have been carried out at the site for determination of the rock mass characteristics and strength. Rigid Plate Load and Flatjack tests were conducted at the site as a part of the geotechnical investigations. The paper summarizes the Geotechnical Investigations carried out so far at Diamer Basha Dam site and gives the details of rock mechanics tests.
Geological Mapping by the Use of Multispectral and Multitemporal Satellite Images, Compared with GIS Geological Data. Case Studies from Macedonia Area, Northern Greece
Authors: Oikonomidis Dimitrios  , Mouratidis Antonios  , Astaras Theodore  , Niarhos Mihail
Published: February 2025

Geological mapping is one of the fundamental acts that a geologist should perform in order to proceed to higher levels of a research. This includes basically, mapping of lithological units and tectonic lines (faults). Satellite images give geologists a unique opportunity to observe the complex interaction of large-scale geological structures that make up Earth's landscape. Furthermore, digital satellite data can be manipulated and enhanced in order to accentuate the surface expressions of certain geological features. In most of the cases, this is usually done in “ideal” test sites, with absence of vegetation, soil cover, etc. In this paper, various digital image processing techniques were applied on Landsat-7/ETM+ and Terra/ASTER satellite images, acquired on different dates, in order to produce the most appropriate images for geological mapping, in typical Mediterranean terrain. Two areas were chosen as case studies, the Kassandra peninsula and Thassos island. Boundaries of photo-lithological units and photo-lineaments are drawn on the above satellite images. The results are compared with digitized geological maps of 1/50.000 scale and are evaluated.
An Approach to Airport Categorization – Category Definition and Quantification for Air Traffic Related Simulation Purposes
Authors: Öttl Gerald  , Böck Philipp
Published: February 2025

Airport categorizations offer a basis to derive representative scenarios for air traffic related simulation purposes. A methodology for an application specific airport categorization was developed as presented in this paper. Existing categorizations were identified to insufficiently reflect operational characteristics of airports and mostly to omit quantitative statements, which are a crucial simulation input. The presented approach shows a way to enhance an existing baseline categorization using application specific airport similarity parameters. A set of typical airports for each category can be specified by analyzing air traffic schedule data. Clustering techniques, the core element of the methodology, are applied to identify outliers, which are subsequently removed. The remaining group of airports is used to calculate the boundaries of the analyzed category as well as the representative scenario parameter values. The proposed approach is presented step by step for one category and the exemplary application in noise trading scheme simulations. Additional results for use in airport capacity analysis are provided. The presented approach offers the possibility to derive traffic scenarios that represent the characteristics of a multitude of airports within one category. In general a different set of similarity parameters can lead to different category boundaries and representative values. The results are application driven, as proven by the examples.
Safety Assessment of a Future Taxi Into Position and Hold Operation by Agent-based Dynamic Risk Modelling
Authors: Stroeve Sybert H.  , van Doorn Bas A.  , Bakker G.J. (Bert)
Published: February 2025

Agent-based dynamic risk modelling supports the design of future air traffic operations by risk analysis methods that account for the performance variability of the interacting operators and systems and the resulting emergence of safety occurrences. The paper shows the application of this modelling approach for a future A-SMGCS level 3 supported taxiing into position and hold operation. It provides preliminary risk results, which are obtained by Monte Carlo simulations of a dynamic risk model and by an evaluation of the risk uncertainty using feedback of operational experts.
High Strength Aluminium Investment casting at Zollern, using the Sophia Process
Authors: Hornung Bernd
Published: February 2025

The investment casting technology offers a wide range of process variations which will be used for the individual needs of applications. The castings are characterized by a high surface quality, close tolerances and high mechanical properties.
Developing Stability Design Criteria for Aluminum Structures
Authors: Ziemian Ronald D.  , Kissell J. Randolph
Published: February 2025

With the advent of the 2010 Aluminum Association's Specification for Aluminum Structures, structural engineers will be required to design using new stability provisions. Second-order effects, including P-Δ and P-δ moments, will need to be directly accounted for in the analysis. Factors known to accentuate these effects, such as geometric imperfections and member inelasticity, will also need to be considered. This paper provides an overview of these provisions and describes a study that investigated their effectiveness.
Efficient Local Navigation Using 1D Image Representations
Authors: Burbridge Chris  , Condell Joan  , Nehmzow Ulrich
Published: February 2025

In this paper a new, efficient approach to accurate image-based homing is proposed for indoor robots that makes use of the ceiling plane. A gradient orientation histogram is built to calculate the rotation of the robot between a target location ‘snapshot’ and the current image perception, and efficient 1D average row and column images are constructed to find the vector pointing to the home location. Our algorithm is ideally suited for use on low-powered, cheap robots where sensing and computational power are limited.
Study on the Relationship between Particle Micro Parameters and Soil Mechanical Properties
Authors: Wang Chengbing  , Zhu Hehua
Published: February 2025

The biaxial test of soil was simulated by using parallel bond model in PFC2d. Through the simulations, the influences of particle micro parameters such as particle contact rigidity, rigidity ratio, friction coefficient and bonded strength on soil mechanical properties were studied, and the micro characteristic of the deformation and failure of soil sample were analyzed. The calculating results indicates that the larger the particle contact rigidity is, the larger the initial tangent modulus, the soil peak strength and Poisson ratio are; the larger the particle rigidity ratio is, the larger the soil Poisson ratio is, while the smaller the soil Young's modulus is. It is also found that when the friction coefficient increases, the soil peak strength and friction angle become larger and the softening character of stress-strain curve presents more obviously, but the soil Poisson ratio decreases; when the bonded strength becomes larger, the soil peak strength and cohesion rise up, then the softening character of stress-strain curve also presents more obviously, while the soil Poisson ratio will be smaller. Finally, a laboratory test of soil sample was simulated by PFC2d, and the calculated results matched the test results perfectly.
Molecular dynamics calculation of infra-red spectra of ultra-dispersed atmospheric moisture
Authors: Galashev A.Y.
Published: February 2025

The absorption and scattering of IR radiation by aqueous ultradisperse systems that absorb nitrogen, oxygen, or argon are studied with the molecular dynamics method on the basis of a flexible molecule model. After nitrogen or argon is captured by an aqueous disperse system, the absorption of the IR radiation by this system increases owing to the enhancement of intramolecular vibrations. It is demonstrated that the integral intensity of absorption of IR radiation decays after water clusters adsorb oxygen. As the nitrogen concentration in a system of water clusters rises, the power of IR radiation emitted by the system increases significantly. The attachment of molecular oxygen by clusters leads to decay of the power of their IR radiation, while the capture of atomic oxygen, on the contrary, is accompanied by an increase in the rate of dissipation of energy accumulated by water aggregates. The power of radiation generated by cluster systems at the expense of thermal energy increases considerably when there is one adsorbed argon atom per cluster and decreases with a twofold increase in the number of argon atoms in clusters.
The anisotropic polarizability of pairs of hydrogen molecules and the depolarized collision-induced roto-translational Raman light scattering spectra
Authors: Li Xiaoping  , Harrison James F.  , Gustafsson Magnus  , Frommhold Lothar  , Hunt Katharine L.C.
Published: February 2025

In earlier work, Li, Ahuja, Harrison, and Hunt have calculated the collision-induced polarizability Δα of a pair of hydrogen molecules at CCSD(T) level with an aug-cc-pV5Z basis, for 178 relative orientations of the pair, with the bond length in each molecule fixed at r = 1.449 a.u. Here we present new results from an expansion of the second-rank tensor components of Δα as series in the spherical harmonics of the molecular orientation angles and the orientation angles of the intermolecular vector. The coefficients in this expansion depend on the separation R between the molecules. We compare the ab initio coefficients with predictions from long-range perturbation theory, including the dipole-induced-dipole interactions at first and second order, higher-multipole induction, effects of nonuniform local fields, hyperpolarization, and van der Waals dispersion. Li and Hunt have derived equations for the long-range coefficients complete to order R-6, using spherical-tensor methods developed by Bancewicz, Głaz, and Kielich for collision-induced light scattering by centrosymmetric linear molecules. We also give new results here for the van der Waals dispersion terms in both isotropic and anisotropic polarizability coefficients. We have calculated these coefficients by 64-point Gauss-Legendre quadrature, using the H2polarizabilities and hyperpolarizabilities at imaginary frequencies computed by Bishop and Pipin, with explicitly correlated wave functions for isolated H2molecules. We show that the ab initio values for the larger anisotropic polarizability coefficients converge to the predictions of the long-range theory, as the separation R between the molecules increases. The coefficients computed ab initio have been used by Gustafsson, Frommhold, Li, and Hunt to calculate the depolarized collision-induced roto-translational Raman spectra of hydrogen gas at 36 K and 50 K out to 800 cm-1, and at 296 K out to 300 cm-1. The general features of the experimental spectra are well reproduced, although the calculated intensities are ~30% too large over much of the frequency range.
Irreducible spherical representation of some fourth-rank tensors
Authors: Bancewicz Tadeusz  , Ożgo Zdzisław
Published: February 2025

A process of decomposition of fourth-rank tensors into parts irreducible with reference to the continuous group of rotation is presented. The transformation matrices between the Cartesian and spherical reducible and irreducible fourth-rank tensors are given and discussed. We have focused our attention to the purely dipolar fourth-rank tensor Ci;jklsymmetric to its last three indices and the dipole-octopole fourth-rank multipolar polarizability tensor E(1,3). The fourth-rank tensors intervene in a number of very important nonlinear optics processes like Kerr effect, intensity-dependent refractive index phenomena, four wave mixing, third harmonic generation and several other effects. Tensors of this kind are also very important in piezo-electric phenomena and in elasticity studies. Cartesian tensor index permutation is discussed as well as its influence on the tensor irreducible spectrum is studied. Several examples concerning fourth-rank tensors are given.
Isophlorin derivatives: Structures and materials for n-Channel Organic Semiconductors
Authors: Jissy A.K.  , Datta Ayan
Published: February 2025

DFT and NMR calculations performed on isophlorin (1) and their derivatives (2–10) show that the 4O and the trans 2O, 2S derivatives (2 and 5) are anti-aromatic. The presence of strong S. . . S pπ-pπbonding interactions stabilizes the planar structure (5) compared to the non-planar cis-isomer (8). Isophlorins are predicted to have very low electron reorganization energies (λelectron~ 0.10 eV) which remain unaffected by puckering through steric interactions or solvation in aqueous media. We predict isophlorins to be the ideal candidates for n-Channel organic conductors.
Prediction of the Axial Capacity of Bored Piles Using Methods Based on CPT and Static Analysis Approaches
Authors: Zein Abdul Karim M.  , Mohammad Samah B.
Published: February 2025

This study aims at evaluating the performance of five methods based on CPT and static analysis in predicting the axial capacity of bored piles installed in some Sudanese soils. These methods were used for estimating pile capacity at six study sites located in Khartoum and White Nile States. Static pile load tests and CPT soundings were performed at adjacent points in each site to enable comparison of measured and estimated data. Pile capacities were determined using the Van der Veen method of load test results interpretation. Statistical analysis was conducted to evaluate the performance of the five methods according to established ranking criteria. Based on the evaluation criteria adopted, Touma and Reese method showed the best performance by achieving the closest agreement between estimated and measured pile capacities whereas the Dutch method showed the lowest overall performance. From comparison of predicted and measured values of the pile end bearing (Qp) and skin friction (Qs) capacity components obtained for an instrumented pile, the Touma and Reese method gave the best comparisons between measured Qpand Qswhereas the Schmertman method showed a quite reasonable estimate of Qs. The other three methods revealed unrealistic and gross over-prediction or under-prediction of the two components of bored pile capacity.
Dynamically Loaded Foundations
Authors: Archer André
Published: February 2025

The purpose of this study was to determine whether the closed form solutions used for the calculations of dynamically loaded foundations are sufficient to predict the actual behaviour of the foundation. The main limitation is that only impact loads are considered and this will limit the closed form solutions used for the study.
Use of Geosynthetics to Improve Seismic Performance of Earth Structures
Authors: Koseki Junichi
Published: February 2025

After reviewing seismic performance of earth structures based on case histories in Japan and relevant model test results, advantages of using geosynthetics in improving their seismic performance are demonstrated. As one of successful applications, geosynthetics reinforced soil retaining walls are highlighted, focusing on several influential factors such as facing rigidity, arrangement and properties of reinforcements, and backfill and subsoil conditions. In addition, further applications of the reinforcement method using geosynthetics are introduced, which include combination with other reinforcement methods, application to bridge abutments and piers, and application to ballasted railway tracks.
Correlations of DCPT and SPT for Analysis and Design of Foundations
Authors: Nyaoro Dalmas L.  , Ibrahim Mwajuma
Published: February 2025

Both Standard Penetration Test (SPT) and Dynamic Cone Penetration Test (DCPT) have been carried out in Tanzania for many years whereby data obtained from these tests have been used for analysis and design of foundations. Data from various geotechnical investigation projects where the SPT and DCPT were carried out alongside one another were analysed and used to formulate correlations between the two tests data for different soil types while considering testing depth for each soil type. From the analysis, it was observed that a strong correlation between DCPT values and SPT values exist. These correlations can be useful in soil investigation works whereby the number of SPT testing involving expensive boreholes drilling can be reduced while supplementing them with DCPT thus enjoy time and cost saving ability of the DCPT at the same time obtaining more detailed information of the ground within the site being investigated.
Geotechnical Investigations: Over-regulated or Under-investigated?
Authors: A'Bear Tony  , Van Rooy Louis
Published: February 2025

The current regulatory environment encourages a minimalistic approach to geotechnical investigations allowing inexperienced or would-be practitioners to carry out, ostensibly, sufficient investigations. The paper argues that the approaches adopted over the preceding decades should be adhered to and that terrain evaluation techniques and the construction of the geological model should be of over-riding importance when carrying out geotechnical investigations.
Microstructure and mechanical behaviour of asaturated compacted scaly clay
Authors: Airò Farulla C.  , Rosone M.
Published: February 2025

The paper presents the results of a research on the influence of structure characteristics on the mechanical behaviour of a saturated compacted scaly clay. To this aim, mechanical properties of compacted scaly clay samples after saturation are compared with the corresponding properties measured on the clay reconstituted in the laboratory. For the stress range explored in the experimental programme, compacted scaly clay samples are stiffer and stronger than reconstituted clay samples owing to their greater density. Collected results are discussed taking in consideration microstructure characteristics of the compacted and reconstituted clay samples.
Characteristics of manmade stiff grounds improved by drill-mixing method
Authors: Zotsenko M.  , Vynnykov Yu.  , Lartseva I.  , Shokarev V.  , Krysan V.
Published: February 2025

The results of investigation of physical and mechanical properties of soil-cement according to composition of soils, brand and cement content, time of mixture setting are given. Impermeability of soil-cement appeared to be significantly less than in the concrete. Recommendations for using soil-cement in reinforcing the soil massifs for increase of its strength, reduction of compressibility, production of pile foundations and landslide control structures are given.
Numerical behavior of a real slope considering climate actions and comparison with in situ readings
Authors: Verde J.  , Cardoso R.  , Barradas J.
Published: February 2025

The displacements and depth of water level were measured in a real slope located in Coimbra, near A1 Motorway. A strong correlation was found between the displacements and climate actions (mainly rain). The displacements were reproduced using program CODE_BRIGHT, which performs a thermo-hydro-mechanical coupled analysis necessary to include climate actions (rain, relative humidity and temperature). The problem is formulated in unsaturated soils domain to allow computing volume changes caused by drying and wetting. The evolution in time of the displacements found in the calculation was similar to the one measured in the real slope showing correlation with climate.
Comportement hydromécanique post-fermeture des cavités remblayées
Authors: Dufour N.  , Wong H.  , Deleruyelle F.
Published: February 2025

L'évaluation de la sûreté d'un stockage de déchets radioactifs en formation géologique profonde nécessite d'apprécier son comportement hydromécanique au cours du temps et notamment pendant la phase post-fermeture où les cavités sont remblayées. Les revêtements des cavités ne sont alors plus entretenus et perdent peu à peu leur intégrité mécanique. Si la roche hôte est saturée en eau et sujette au fluage, un rééquilibrage hydromécanique complexe s'opère alors entre celle-ci et les remblais et il est important d'étudier si ce phénomène pourrait augmenter la migration d'éléments radioactifs.
Case history: Influence of ground water level on vibrations induced by heavy forging hammers
Authors: Quinteros S.  , Schneider H.R.
Published: February 2025

Heavy forging hammers in an industrial complex in Switzerland produce vibrations which are felt in surrounding residential areas as far away as 800 m. The current case history documents several campaigns of recording vibrations at the source as well as received in a 3-storey house at a distance of 410 m from the forging hammers. The vibrations recorded on the third floor of the house clearly exceeded the acceptable values at certain times, whereas they did not exceed the limits at other times. The relevant subsoil conditions and properties are known from seismic and geotechnical investigations. The subsoil consists of gravelly material with a highly fluctuating groundwater table. The groundwater table is influenced by a nearby river. It exhibits fluctuations of several meters, continuously recorded by a piezometer. Because the intensity felt by the inhabitants and also measured at the receivers varied considerably over time, it was suspected that the groundwater level in relation to the foundation base of the forging hammers could cause this variability even during constant forging operations. Detailed dynamic Finite Element Analyses (FEA) have been carried out to investigate the influence of the fluctuating groundwater level on the reduction of the vibrations travelling through the subsoil. The FEA clearly showed the groundwater table fluctuations to have a considerable influence of up to 35% on the vibrations felt and recorded at the reference house. The active control of the groundwater table along with other vibration reduction measures are shown to reduce the vibrations to acceptable values.
The performance of prefabricated vertical drain (PVD) preloading with and without vacuum and heat
Authors: Saowapakpiboon J.  , Bergado D.T.  , Teerachaikulpanich N.  , Voottipruex P.
Published: February 2025

This paper focuses on the performance of prefabricated vertical drain (PVD) improved soft Bangkok clay in accelerating the rate of consolidation by using vacuum and heat preloading. Large scale consolidometer tests were performed with PVD improved reconstituted specimens using surcharge preloading (PVD only), surcharge combined with vacuum pressure preloading (Vacuum-PVD) and surcharge combined with heat (Thermo-PVD), respectively. Subsequently, the flow parameters were back-calculated based on Hansbo (1979) method by expressing in terms of the horizontal coefficient of consolidation (Ch) and the ratio between the horizontal hydraulic conductivity in undisturbed zone (kh) to the horizontal hydraulic conductivity in smear zone (ks) or (kh/ks). The Chwere 1.93 m2/yr, 2.23 m2/yr and 4.17 m2/yr for PVD, Vacuum-PVD and Thermo-PVD, respectively, with corresponding, kh/ksvalues of 3.0, 2.7 and 1.4, respectively. Thus, the Vacuum-PVD can increase the horizontal coefficient of consolidation, Chresulting in faster rate of settlement at the same magnitudes of settlement compared to PVD. The Thermo-PVD can increase further the coefficient of horizontal consolidation, Ch with the associated reduction of kh/ksvalues by reducing the drainage retardation effects in the smear zone around the PVD and consequently, faster rates of consolidation were obtained.
On the properties of Cambrian clay and sandstones
Authors: Mets M.  , Miljan J.  , Raudsepp R.
Published: February 2025

In present paper a overview of properties of Cambrian clay and sandstone in Estonia is given.
The influence of stiffness anisotropy on the behaviour of a stiff natural clay
Authors: Grammatikopoulou A.  , Schroeder F.C.  , Kovacevic N.  , Germano V.  , Gasparre A.
Published: February 2025

This paper assesses the effect of stiffness anisotropy on the behaviour of a stiff natural clay. London Clay was chosen as an example of such a clay. An anisotropic non-linear elasto-plastic model is used to simulate a number of laboratory tests from a recent advanced investigation on London Clay and the predictions are compared with those of an isotropic model. The predictions of the two models are then compared in the numerical analyses of a tunnel constructed within the London Clay.
Performance analysis of piled raft foundations in comparison with conventional foundation systems by using finite element method
Authors: Yalcin Dayioglu A.  , Incecik M.
Published: February 2025

In the research conducted by the authors, the performance of piled raft foundations in comparison with raft foundations and conventional pile foundations under vertical and horizontal loading is analysed by means of PLAXIS 3D finite element program, which is a rigorous computer-based analysis method. In this context, total settlements, differential settlements and bending moments on the raft are examined. In conclusion, it has been found that in hard soils, especially under combination of vertical and lateral loads, piled raft foundations provide the most economical design within adequate margin of safety.
Stabilization of gravel deposits using microorganisms
Authors: van der Star W.R.L.  , van Wijngaarden-van Rossum W.K.  , van Paassen L.A.  , van Baalen L.R.  , van Zwieten G.
Published: February 2025

One of the techniques used for the construction of underground infrastructure is horizontal directional drilling (HDD). This trenchless method is complicated when crossing gravel deposits as a borehole in coarse gravel tends to collapse, causing the drill pipe to get stuck or the failure of installation of the product pipeline due to exceeding pull forces. In order to find a solution for the problem of borehole instability, the Biogrout process was adapted for borehole stabilization in gravel. In the Biogrout process, loose sand is converted into sandstone by injection of a dedicated mixture in the underground, which stimulates micro-organisms to catalyze chemical reactions leading to the precipitation of calcium carbonate (CaCO3) crystals. These crystals form ‘bridges’ between the grains, increasing the strength and stiffness of the material. After a first successful test on lab scale in 2008 in which gravel was cemented, a 3 m3container was treated after which a hole successfully was drilled through it using HDD equipment. Following the success of this container test, two field applications were performed as part of the installation of two 48 inch steel gas pipelines with a length of 600 and 900 meter near Nijmegen NL. During these field applications twice a volume of 1.000 m3gravel was stabilized in only 7 days each time using the Biogrout technique, after which a HDD was performed successfully.
Design, load tests & completion of bored piles 80 m depth in Pliocene clays on a Danube bridge
Authors: Rodríguez Ballesteros F.  , Gómez Burgaz G.  , Gutiérrez Manjón J.M.
Published: February 2025

The process from design to execution of the foundations of Danube Bridge Vidin-Calafat (Bulgaria-Romania border) is summarised. The foundations are made of 2.0 m and 1.5 m diameter floating concrete bored piles. excavated mainly on Pliocene clay that is founded below alluvial strata or loessian soils with variable thickness around 20 m. For the design the focus was put on the triaxial and the pressiometric tests carried out inside investigating boreholes. To lower the safety factor and make more precise the pile lengths, several loading tests on trial piles were made (a total of 6 O-cell tests). This paper emphasizes specially the parameters deduced from these tests and its correlation with .the previsions based on design. From the analysis of the O-Cell Test results some conclusions were derived: the loading tests showed that the calculus parameters derived from the tests were placed between those obtained from the triaxial tests and from the pressiometric tests; and that the ultimate values from loading tests matched to the limiting values established in the specialized literature and common standards for overconsolidated clays.
Prevention of liquefaction during earthquakes through Induced partial saturation in sands
Authors: Eseller-Bayat E.  , Yegian M.K.  , Alshawabkeh A.  , Gokyer S.
Published: February 2025

Liquefaction has been a significant earthquake-induced phenomenon which can cause massive damages to our infrastructures, during earthquakes. In this paper, a new liquefaction mitigation measure was introduced: “Induced Partial Saturation (IPS)”. This measure has a great potential to be a cost-effective and practical solution for new as well as existing structures. IPS aims to improve the resistance of liquefiable sands by introducing some amount of air/gas in the voids of the sand. The air/gas entrapped sand specimens were prepared by two techniques developed under laboratory conditions: 1) by generating oxygen and hydrogen gases through Electrolysis and 2) by assisting air entrapment in the voids by draining and reintroducing water in the fully saturated sand specimens: Drainage-Recharge (D-R). Fully and partially saturated large sand specimens were prepared in a special liquefaction box (NULB: Northeastern University Liquefaction Box) and tested under uniform cyclic simple shear strain tests performed with the use of a shaking table. The test results demonstrated that initial liquefaction was prevented in air/gas entrapped specimens and excess pore water pressures were reduced significantly. Moreover, cross-well radar measurements were performed for the detection of gas entrapped in the specimen. Through cross-well radar technique, the different electromagnetic conductivity characteristics of gas and water enabled the detection of the gas entrapped in the specimen in a non-destructive way. As another important task in this research, the long-term sustainability of entrapped air/gas in the specimens was investigated under hydrostatic, vertical upward/downward and lateral flow regimes. The results provided evidence that air/gas bubbles remain entrapped in the sand, providing evidence that Induced-Partial Saturation (IPS) holds promise for use as a sustainable liquefaction mitigation measure.