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This study presents the results of a series of reduced scale model tests carried out to investigate the bearing capacity and displacement behaviour of strip footings resting near both unreinforced ...

A micromechanical experimental study is presented in this paper investigating the normal contact response of quartz sand grains under cyclic loading. Sand grains with clean surfaces, termed uncoate...

Many bridge abutments suffered failures due to large lateral deformations due to seismic shaking. During earthquakes, bridge abutments restrict the bridge deck's intrusion towards the backfill soil by generating passive earth pressure, which provides resistance to lateral deformation. As a result, the backfill takes the earthquake induced inertial forces transmitted from the bridge superstructure through abutment. Now a days, GRS bridge abutments are widely used due to their many advantages. In this paper, the behaviour of these GRS bridge abutments under large displacements such as 1 m lateral push into the soil due to the impact of bridge deck has been analysed and studied. It is observed that the GRS abutments with longer geogrids are observed to show better passive resistance.

Sonic booms or disruptive explosions cause differing response in wildlife. In May 2021, when missiles were fired at urban areas in Israel, we observed the responses of breeding common swifts (Apus apus). In both nests, the initial boom resulted in a startled awakening of the swifts. In one case, a parent engaged in displacement behaviour of feeding the young while in the second case a parent tried to clamber up the walls. Our data support earlier studies that although auditory booms are disruptive, they do not result in nest abandonment or nest failure.

Several pipeline projects have been proposed in the world in recent years owing to the rapid growth of the petroleum industry. Onshore pipeline systems are usually buried above the natural groundwater table, where the soil is typically in an unsaturated condition. Rational interpretation of these pipelines is possible by extending the mechanics of unsaturated soils. In this paper, the axial force exerted by way of the relative movement on a prototype steel pipeline in sand under both saturated and unsaturated conditions is determined from laboratory investigations using specially designed equipment. The test results under the unsaturated condition showed significantly higher axial force on the pipeline compared to the saturated condition, attributable to the contribution from matrix suction. Two analytical models proposed in this study, which take into account the influence of matrix suction and dilation, successfully predicted the peak and residual skin friction along the pipe surface. The framework developed, based on experimental studies and analysis of the results and the proposed models that use saturated shear strength parameters and the soil-water characteristic curve, is promising for generating simple tools for the design of pipeline infrastructure buried in sands to ensure their stability and safety, and at the same time provide economical solutions.

Spatio‐temporal distribution is fundamental information for species of conservation concern, like sea turtles, that are threatened by anthropogenic activities at sea such as fishing. While coarse‐scale distribution information is available for several sea turtle populations, fine‐scale distribution informing on hot‐spot areas for spatial management is more difficult to obtain. Here a citizen science approach involving tourism boats was undertaken to investigate the spatio‐temporal distribution of the loggerhead sea turtle (Caretta caretta) in the Pelagie Archipelago, located in a major foraging area for this species in the Mediterranean and where high fishing‐induced mortality occurs. The study was designed to provide data of absence and total sampling effort, commonly under‐reported in citizen science studies, allowing comparison among zones and periods. This was complemented by reports from fishing vessels. Tourism boats reported 584 loggerhead turtle sightings during 1718 daily trips and fishing vessels reported 280 loggerhead turtles captured during 1040 fishing days. The results indicate a strong heterogeneous distribution in the Archipelago, with a low turtle occurrence around the main island, Lampedusa, where the highest human presence and activity occur. This may represent rare evidence of displacement behaviour of turtles that is worth further investigation. This also suggests that the current small marine protected area around Lampedusa has a low conservation impact. Zones with higher loggerhead turtle occurrence appear to be in the south and the west parts of the Archipelago, suggesting that spatial management would be possible when relatively small hot‐spots have been identified through specific surveys. This study shows the potential of citizen science for providing preliminary information to guide more demanding and specific investigations. Such an approach may tremendously and rapidly improve the current knowledge on fine‐scale sea turtle distribution in regions with a great extension of coastlines and intensive tourist activities, such as the Mediterranean.

The present study aimed to investigate whether straw provision in pigs increases positive emotions, indicated by tail movement, and reduces poor welfare indicators (agonistic and displacement behaviours), including indicators of negative emotions (ear movement). Comparisons between Straw and Control sessions were analysed from video recording for all parameters. 15 mini-pigs participated in a three-week study. Depending on the week, animals were included in Straw or Control sessions. During Straw sessions, pigs were placed in their own pens where straw was introduced and continuously provided for one week. During Control sessions, pigs remained in their pens with no additional stimulus. Pig behaviours were video-recorded four times during each session and scored. Results showed that ear movement frequency was significantly lower in the Straw than in Control session (p = 0.005); agonistic behaviour frequency and duration were significantly lower in the Straw than in Control session (p = 0.013 and p = 0.0004, respectively), and displacement behaviour frequency and duration were significantly lower in the Straw than in Control session (p

Buildings possessing an asymmetrical arrangement of structural elements are torsionally unbalanced and can be vulnerable in a seismic event. Building codes of practices typically recommend the use of three-dimensional dynamic analysis to determine the seismic demands of a multi-storey building. Whilst most design practices are well equipped with commercial software for undertaking such analyses, designers often find it difficult to verify results. Much of the published technical articles present findings for buildings based on an idealised single-storey model. As a result of challenges in dealing with real multi-storey buildings, there has been very limited uptake of research findings in design practices. This article presents a three-tiered approach of estimating the displacement behaviour of the building in term of 3D/2D displacement ratio. The estimate can be used for verifying results reported from a computer package conveniently. The quick method provides predictions of the 3D/2D ratio and only requires the gross plan dimensions of the building to be known. The refined method requires knowledge of the torsional stiffness properties to be known, whereas the detailed method requires the eccentricity properties to be known as well. The proposed methodology is robust and reliable, as is demonstrated by case studies undertaken on six real multi-storey buildings.

The identification of the slope deformation characteristics upon rainfall plays an important role in providing early warning information and implementing emergency remedial actions before landslide occurs. In this study, a coupled hydro-mechanical formulation of finite element analysis was performed to investigate the displacement behaviour of slopes triggered by rainfall infiltration. The simulation results showed in good agreement with experiment result. The model study was then carried out to investigate the hydraulic and deformation response of the shallow slope. The numerical results revealed that the developed slope displacement with time can be divided into three stages, namely constant, accelerated, and critical deformation stages, corresponding to various rates of slope movement and porewater pressure development stages. Finally, the relationships of slope displacement magnitude with the factor of safety that established from this study can be seen as a good indicator for shallow landslide hazard assessment.

After reviewing the complex and varied geology of France, the soil investigation commonly performed for pile projects is described. The types of piles and the execution methods used in the country are also given. The design rules for axially loaded piles, recommended by the French code for foundations ‘Fascicule 62-V (1993), based on Menard pressuremeter test (PMT) and on cone penetration test (CPT) results are presented in detail (including formulae and charts). The relevant factors of safety are given, both for ultimate and for serviceability states. The t-z method for obtaining the axial load-axial displacement behaviour of a pile, from PMT results, is described. Finally, the national practice for integrity testing and for load testing of piles is given.

The characterisation of in-plane shear behaviour during textile reinforcement forming is one of the most important factors to insure the quality of the preforms before resin impregnation. All experimental and numerical studies on the in-plane shear behaviour concern orthogonally fabrics, interlaced by weaving or stitched for NCF preforms. In the present work, the in-plane shear behaviour of non-orthogonally interlaced fabrics manufactured by braiding is studied. Braided fabrics are widely used as textile reinforcements to manufacture advanced composite parts. Due to the non-symmetric structure of braided reinforcements, it is necessary to study this shear behaviour not only in axial direction but also in transversal direction. A geometric criterion and an analytical model for in-plane shearing characterisation by the bias-extension test are developed firstly for any textile structure. Then, two types of fabrics, Flax/PA12 and E-glass braided fabrics, are performed in bias-extension tests for validating the theoretical model. Analytical and experimental results present a good agreement that demonstrates the bias-extension test can be used to characterise the in-plane shear behaviour of braided reinforcements. Moreover, the in-plane shear behaviour of the braided samples with different ratios of length to width is also discussed to analyse the influence of the dimension ratio on tested samples. The results show that varying dimension ratio does not change the shear moment/shear angle behaviour but could affect the shear load/displacement behaviour.

A widely adopted technique for retrofitting of RC beam at soffit is through adhesively sticking external plate of FRP/Steel. However, an increase in applied load leads the plated beam to fail prematurely in debonding and peeling that largely develop from tension region; thereby, compromising the composite action between the plate and the beam that was initially designed to fail in a desired capacity. In recent decades, a significant research has been focussed to understand the influence of premature modes of failure on the capacity of plated beam; however, not much success is achieved in predicted premature failure, which is largely pertaining to complex nature of the materials involved. As premature modes of failure are highly uncertain, the author suggests that any such investigations are not complete without a proper characterisation (qualitative and quantitative) of different modes of failure in terms of their relativ e behaviour and dependency on different parameters. To understand and address these issues, author has proposed a quantitative parameter brittleness of failure that can be used to relate different modes of failure and measure their dependencies on beam parameters. The objective is achieved through a non-linear numerical tool model generated using ABAQUS, with the combination of discrete and continuum models, whose accuracy is validated through literature in terms of modes of failure (behaviour: location, initiation and propagation), load/displacement behaviour and capacity. At interface this was possible by adopting Cohesive Zone Model innovatively such that the same model could be used to define adhesive parameters as well as crack properties; thereby, through this merging technique it is now possible to control interfacial debonding

Stiffened steel columns are widely used in bridge piers due to their structural and constructional efficiency. The bridge pier is one of the main structural components in elevated highway transportation. The ability of structures to survive severe earthquakes depends on both strength and ductility. In this study, the stiffeners with different cross-sectional configurations are introduced to improve the strength, ductility and energy absorption capacity of thin-walled steel box columns. All cross-sections are designed with the same cross-sectional area and height for different stiffener arrangements. The columns are analysed by finite element method, incorporating both material and geometric nonlinearities under constant axial load and lateral cyclic loading. Using the lateral loadlateral displacement behaviour, the cross-section with two middle stiffeners shows high strength and ductility capacity. But examining energy absorption behaviour, the cross-section with corner stiffener shows high capacity among analysed columns. Therefore, by considering strength, ductility and energy absorption capacity, the best cross-section is identified as the cross-section with two middle stiffener arrangement with a particular cross-sectional area compared with other cross-sections. In addition to that, local buckling patterns of the columns are examined at different displacement levels to understand the failure modes.

The failure mode of anchorages placed close to the concrete edge and loaded in shear perpendicular towards the edge is often governed by the concrete edge breakout failure. The design provisions for concrete edge failure given in the current codes are limited in their application for anchor groups with rectangular anchor configurations only. The number of anchors in a row is limited to three for anchorages without, two for anchorages with hole clearance. Furthermore, for anchor groups with multiple anchor rows loaded in shear perpendicular and towards the edge, the failure load may be calculated by assuming the failure crack originating from the front anchor row (EN 1992-4) or from the back anchor row (fib Bulletin 58, ACI 318). The aim of this experimental study was to investigate the behaviour of shear loaded anchor groups of rectangular, triangular and hexagonal configurations undergoing concrete edge failure. A comprehensive experimental program was carried out on single anchors and anchor groups of different configurations to obtain information on (i) the group behaviour, (ii) the crack initiation and propagation, (iii) the influence of the displacement behaviour of single anchors on the behaviour of anchor groups and (iv) the influence of hole clearance pattern. The testing concept, test setup and the detailed evaluation of the test results such as load-displacement curves of the groups, load-displacement curves of single anchors, measurements on the hole clearance pattern and the investigation of the crack pattern and failure mode are discussed in this paper. Based on the evaluation of the test results presented here, a new analytical model is being developed for the concrete edge failure mode of shear loaded anchor groups that will be presented in a future paper.

This work is dedicated to the study of the large-displacement behaviour of a spiral spring. Parameters that influence the local torsion stiffness of the beam that constitutes the spiral are varied and their effect is studied. Cross-sectional shape, orthotropic material orientation and prestress are the three classes of parameters that are varied. The effect that the local change in torsional stiffness has on the overall behaviour is illustrated in a linearised way by comparing in-plane and out-of-plane stiffnesses, and nonlinearly, by inspecting a graphical representation of the potential energy field of the system. Several embodiments composed of multiple spirals are showed to illustrate how the understanding of the nonlinear behaviour could be exploited in conceptual design of compliant mechanisms.

In this paper, the strength safety of a fuse cock main body has been analyzed by the finite element method. The stress and displacement behaviour characteristics have been investigated for thickness variations at the region of (T) between a ball valve and a fuse cock safety connector. The FEM analyzed results recommend that the optimized thickness at the region of (T) is from 1.55mm to 1.6mm for the supplied gas pressure of 1.5~3.5MPa. This is considered for the optimized strength safety and light weight of a fuse cock main body.

This paper presents the results of laboratory model tests and corresponding numerical analyses carried out on a model slope representing an actual railway embankment which failed on several occasions after overnight heavy rainfall. In the absence of any field data, the displacement behaviour and failure pattern of the model embankment slope are observed in the laboratory under fully saturated condition and under a static load at the crest simulating the actual rail loads. A study is also performed by reinforcing the slope with thin jute tassels of 1 mm diameter. The numerical simulation of the model tests is performed by a commercial program called FLAC. The responses of the model slope with and without jute tassels are observed in fully saturated condition. Significant improvement in deformation of the slope is observed both in the case of numerical analyses and laboratory experiments when jute tassels are utilized as a slope protection measure. The study indicates that the stability of the railway embankment can be improved significantly at low cost by reinforcing it with jute tassels.

A three-dimensional time-stepping dual reciprocity boundary element method (DRBEM) modelling was investigated for anisotropic functionally graded piezoelectric Structure (FGPS) under the influence of gravitational waves. The FGPS is assumed to be graded through the thickness. The basic aim of this paper is to describe anisotropic displacement behaviour of the homogeneous piezoelectric structures (HPS) and FGPS under the influence of Gravitational waves. The accuracy of the proposed method was examined and confirmed by comparing the obtained results with those known previously. Understanding the behaviour of anisotropic FGPS under the effect of gravitational waves is the key to extending the application of these structures.

Practical experience suggests that stealing behaviour of dairy cows may affect the results in feeding trials, when automated feed troughs are used for measuring and controlling the feed intake. The objectives of the present study were to analyse the stealing behaviour from the log data of the feeder, quantify its biasing effects and make a proposal to solve the problem. Twenty dairy cows, ten of which were previously observed to steal roughage, were housed in a loose-housing system with 12 feed troughs (1.66 cows per trough). To induce the stealing behaviour, the animals were offered two kinds of feed, partial mixed ration (PMR) and silage (SIL). In a learning period (P0, three days), all the cows had free access to all the troughs. In periods 1 (P1, seven days) and 2 (P2, 14 days), 10 cows had access only to the SIL troughs and 10 cows only to the PMR troughs. In P2, barriers were built to prevent the stealing behaviour. In period 3 (P3, four days), the structure of the barriers was improved. We analysed two types of stealing behaviour: (1) stealing feed over a closed gate (S-GATE) and (2) stealing feed by displacing a legitimate cow from a trough (S-DISP). S-GATE by the SIL group, as measured by the average daily frequency and the amount of stolen feed (the PMR feed), decreased significantly (frequency: P =0.001; dry matter: P =0.001) from P1 (frequency: 8.0±2.54; dry matter: 0.7±0.26kg; mean±SEM) to P2 (1.0±0.66; 0.1±0.06kg) and remained the same in P3 (1.0±0.47; 0.1±0.07kg) as in P2. The frequencies of S-DISP, where the PMR feeding animals were displaced, was lower ( P =0.022) in P3 (0.0±0.03 per animal per 24hours) than in P1 (1.3±0.60) and P2 (1.3±0.53), but the differences were not statistically significant in the post hoc analyses. There were remarkable individual differences in the frequencies of how often a cow was detected to steal over a closed gate or being displaced from a trough. To conclude: stealing occurred frequently enough to bias the feed intake results in the experimental setup where cows clearly preferred one feed (PMR) over the other (SIL). However, appropriate barrier structures alleviated the problem markedly.

Steel bracing has proven to be a very powerful method to improve the seismic behaviour of reinforced concrete frame structures. In general the steel braces are indirectly connected to the RC frame via additional steel frames that are in turn fixed to the RC frame using post-installed anchors or reinforcing bars. However, this method comes with several shortcomings including increased weight and a disruption of the buildings function during installation. Therefore new connection approaches were developed where the braces are directly connected to the RC frame. One of the most promising solutions is the connection by means of post-installed anchors to connect the bracing to the frame corners. Using this type of connection allows an effective and low invasive strengthening of the structure. In this case the performance of the retrofitted structure is highly dominated by the performance of the post-installed anchors, since the imposed seismic demands are rather high. Therefore it is deemed necessary to assess the anchor performance under seismic actions, especially their displacement behaviour in the post-peak range. The current guidelines for seismic qualification of anchors only provide a force-controlled assessment procedure which is valid for non-structural connections but is not sufficient to obtain the information required for the assessment of their seismic performance in structural applications. A new displacement-controlled approach for the assessment of post-installed anchors under seismic conditions is presented. This approach allows the evaluation of the complete load-displacement behaviour as well as the hysteretic response of the anchors even in the post-peak range. A comparison with existing force-controlled assessment procedures shows that this approach is more suitable for the assessment of anchors used in structural strengthening applications under seismic actions.

Behavioural coping strategies represent a key means by which people regulate their stress levels. Attention has recently focused on the potential role in coping of 'displacement behaviour' - activities such as scratching, lip biting and face touching. Increased levels of displacement behaviour are associated with feelings of anxiety and stress; however, the extent to which displacement behaviour, as a short-term behavioural response to emotionally challenging stimuli, influences the subsequent experience of stress remains poorly understood. The aim of this study was to investigate the potential role of displacement behaviour in coping with stress. In a study population of 42 healthy adult men (mean age = 28.09 years, SD = 7.98), we quantified displacement behaviour during a Trier Social Stress Test (TSST), and used self-report questionnaires to assess trait and state anxiety before the TSST, and the experience of stress afterwards. We predicted displacement behaviour would diminish the negative impact of the stressful situation, and hence be associated with lower post-TSST stress levels. Furthermore, we predicted displacement behaviour would mediate the link between state and trait anxiety on the one hand and the experience of stress on the other. Results showed the rate of displacement behaviour was positively correlated with state anxiety but unrelated to trait anxiety, and negatively correlated with the self-reported experience of stress, in agreement with the idea that displacement behaviour has a crucial impact on regulation of stress. Moreover, serial mediation analyses using a bias-corrected bootstrapping approach indicated displacement behaviour mediated the relationship between state anxiety and the experience of stress, and that state anxiety and displacement behaviour - in combination, respectively - mediated the link between trait anxiety and experience of stress. These results shed important new light on the function of displacement behaviour, and highlight promising new avenues for research into emotional expression and stress regulation.

One of the most common causes of ground failure during earthquakes is the liquefaction phenomenon, which produces severe damage to property. Although methods are available for seismic analysis of pile foundations, most of them consider soil to be an elastic material. Collapse of piled foundations in liquefiable areas has been observed in most recent strong earthquakes despite the fact that a large margin of safety is employed in their design. Lateral spreading of gently-sloping deposits of liquefiable sand is a cause of much damage in earthquakes, reportedly more than any other form of liquefaction-induced ground failure. The present investigation finds the effect of earthquake induced lateral soil movement on lateral pile capacity. Parametric study is carried out on the same model by changing the ground surface to different slopes on the top of the non liquefiable layer and by changing the length of the pile in the bottom layer of the non liquefiable layer. The paper focuses on the behaviour of pile under lateral soil movement due to earthquake. The bending moment and displacement behaviour of pile is studied in detail for different slope conditions.

Thin sheet materials of low bending stiffness but high membrane stiffness are often corrugated in order to achieve improvements of several orders of magnitude in bending stiffness with only minimal increases in weight and cost. If these corrugated sheets are initially curved along the corrugations, much of this stiffness gain is lost. In return, the sheets are then capable of significant elastic changes in shape overall, including large changes in overall Gaussian curvature. These shape changes are described here by non-linear and coupled kinematical relationships, which are verified against experiment and finite-element simulations. It is found that gross simplifications can be made about the large displacement behaviour of such shells without a loss of accuracy.

The present study concerns the analysis of the asymmetric displacement behaviour of the rear part of a motorcycle. Stylistic reasons led to the design of a vehicle with only one suspension located on the left-hand side. Experimental tests performed on a circuit with seven obstacles along a straight line confirmed that the bending displacement is higher on the right-hand side than on the left. This study aimed to perform a structural optimisation of the components involved at the rear end of the motorcycle, to find a solution to the problem. A hybrid approach is applied: the force acting on the suspension and bending displacements at the rear end were simultaneously measured in working conditions; a finite-element method model was then set up, validated and applied for design optimisation purposes. Both methodological aspects and applicative results are presented and discussed. Finally, a solution in accordance with design specifics is proposed.

Wing-Tagging Temporarily Affects Time Budgets of Large Gulls We studied behaviour of large gulls recently marked with wing-tags at loafing sites at an inland refuse dump using focal birds. During the first 3-4 weeks after marking, wing-tagged gulls spent more time preening at the refuse dump than unmarked birds, which usually did not preen there, while no difference between those two groups was observed at other sites. The possible reasons for preening on the refuse dump are that marked gulls either avoided flying to the loafing water because wing-tags impaired their flight, or showed displacement behaviour.

This paper presents workspace analysis for a three-degree of freedom(3-DOF) compliant parallel mecha-nism(CPM) using SimMechanics software based on PZT's output forces. In order to meet the requirements of precision mechanism for application, it is necessary to evaluate the workspace performance of the designed stage, taking the fabrication tolerance and modeling inaccuracies of flexure joints into consideration. The work on obtaining the workspace of a manipulator was done in past using the geometrical approach, screw theory, and other methods. Unlike the above aforementioned methods, using SimMechanics to get the workspace is much easier. In this paper, the stage is modeled with elasto-slide element and then the PZT force and displacement behaviour are obtained, based on the pseudo-rigid-body (PRB) method, the model of CPM is established, and a complete analysis of a planar 3-RRR parallel flexure based manipulator is made.

We performed a factorial experiment to investigate the effects of current and prey odours (mussels) on the displacement behaviour of the sea star Asterias vulgaris (Verrill, 1866). This sea star is a common subtidal predator of sessile and slow-moving animals in the western North Atlantic Ocean. In the presence of current and prey odours in a flume, sea stars oriented themselves upstream and 70% succeeded in finding the prey. Also, the degree of orientation toward the prey increased as the sea star approached the prey. In contrast, only 5% of individuals tested in still water found the prey. Thus, for A. vulgaris the presence of macroscale flow is an essential condition for locating distant prey. Sea stars tested in current alone showed rheotactic behaviour, moving diagonally upstream. This behaviour should enhance the probability of encountering prey odour plumes in the field. Sea stars moved faster and straighter in flowing water than in still water. The slow movement of A. vulgaris in still water probably minimizes costs of foraging when there is a low chance of finding prey and the straight diagonal movement in current should ensure that the sea star continuously samples new areas, rather than resampling the same odour-free area.

Experimental investigations of the response of several elastic solids, carried out using an instrumented indentation machine, are described. These solids include a natural rubber compound, neoprene, and three different compositions of poly(dimethylsiloxane) (PDMS) when they were indented with tungsten carbide cones of included angles of 60°, 90°, 120° and 136°. It is shown that, except for the case of the 60° cone loading on to the blocks of PDMS (1 : 10) and PDMS (1 : 20), the indentation load versus indenter displacement behaviour of all the elastic solids corresponding to all the conical indenters is well fitted by the 1965 Sneddon theory for frictionless indentations. Video camera sequences of the process of indentation by cones of different included angles into the blocks of PDMS (1 : 10) and PDMS (1 : 20) have also been taken from which measurements of the elastic deformation of the indented surface have been made. It is shown that the magnitude of the elastic deformation of the indented surface clo...

In this paper a new analytical model is proposed to analyse the displacement behaviour of a tunnel face reinforced by bolts, using the homogenization approach for periodic media. Based on previous works, this new model was developed to take into account a finite bond strength of the grout–soil interface, which is more realistic than the perfect bonding assumption. The interface behaviour is simulated by an elastic – perfectly plastic constitutive law. The interface sliding occurs when the shear stress reaches the bond strength. This new feature allows for a more correct estimate of the bolt tension and the quantitative contribution of the bolt to reducing displacement of the ground surface. Despite using less restrictive hypotheses, the solution process remains sufficiently simple, thus preserving the analytical character of the solution. This new analytical model has been validated by three-dimensional (3D) numerical calculations using the finite difference code FLAC3D and by comparing its predictions with in situ data from the Tartaiguille Tunnel construction project, which forms part of the Mediterranean TGV (high speed railway) network. The developed approach results in simple and efficient design tools, which are very useful at the preliminary design stage of a project.Key words: tunnels, soil–structure interaction, reinforcement, numerical modelling and analysis, deformation, plasticity.

Japanese Black (a beef breed) develop frequent tongue-playing under intensive husbandry systems. The following were investigated in 16 artificially reared calves kept in two different farms: (1) the development of tongue-playing behaviour with age; (2) whether or not a dummy-teat could stimulate sucking and suppress behavioural and physiological stress and tongue-playing; (3) whether or not feeding of short cut hay could promote behavioural and physiological stress and tongue-playing; and (4) whether or not individual-housing could promote behavioural and physiological stress and tongue-playing than group-housing. Grooming as common displacement behaviour (indicator of behavioural stress) and physiological stress indicators such as plasma ACTH and cortisol concentration were measured to evaluate stressfulness of these treatments. The correlation between these indicators and tongue-playing was investigated. Four blocks (two individuals per block) were established on each of the two farms, resulting in an experimental design with a three-way classification (dummy-teat: offered or not; hay: short cut or long cut; and housing: individual or group-housed after weaning). Short cut hay was approximately 5 cm in length, whereas long hay was approximately 50 cm in length. Each of eight calves under 2 months old was provided with a dry rubber teat fitted to the wall. Tongue-playing was performed after forced weaning at 42 days of age. A little sucking was directed towards the dummy teat. Offering a dummy-teat neither influenced the stress state of the calves nor suppressed inclusive tongue-playing (consisting of tongue-playing and para-tongue-playing). Feeding of short cut hay elevated the plasma level of ACTH and cortisol at 150 days of age in calves. However, feeding of short cut hay did not lead to inclusive tongue-playing. Inclusive tongue-playing appeared more in individual-housed than group-housed calves. Calves spent less time suckling, feeding, exploring and moving in individual-housing than group-housing in this study condition. Calves could perform inclusive tongue-playing under long-term frustration by suppressed suckling, feeding and boring environment.

Displacement acts, once a hot topic in ethology, but wrapped in silence for two decades since, have recently been suggested to indicate and relax social tension (Maestripieri et al., 1992; Wiepkema, 1987). The first of these contentions seems to be in contradiction with some of the classical ethological studies of displacement behaviour, in particular those supporting the disinhibition hypothesis, since the latter would not predict any positive correlation between amount of tension (i.c. intensity of the conflict) and the occurrence of displacement acts.

A theoretical and experimental study of displacement development in cation-exchange displacement chromatography is carried out. Simulated displacement chromatograms are generated using a numericl model of displacement chromatography, which employs the steric mass action (SMA) formalism to describe the multicomponent nonlinear adsorption of proteins and polyelectrolytes. Simulated profiles of transient displacement chromatography are compared with experimentla displacement over a ranve of operating conditions, and the model accurately predicts transient displacement behaviour. The success of the model indicates that the SMA formalism is an appropriate tool for prechromatograms indicate that significantly higher throughputs can be achieved by operating these protein displacement systems under nondeveloped conditions. In addition, displacement development proceeds faster at lower salt concentration, indicating that a reduction of the displacement systems. This work sets the stage for the optimization of protien displacement chromatography.

The immiscible displacement of a wetting fluid by a non-wetting fluid in a disordered porous medium is studied in the capillary region, i.e. when capillary forces are dominant, by using the invasion percolation model to describe the displacement mechanism. The porous medium is represented by a two-dimensional network of interconnected capillaries whose radii follow a uniform size distribution. Disorder is assigned to the medium by considering the probabilities of occurrence of inaccessible pores, ps, and non-conductive capillaries, pb. It is found that the dynamic behaviour of the displacing fluid and the fraction of invaded pores depend on the degree of disorder of the medium. The results can provide an interpretation of the effects of the dead-end pore volume on the oil recovery and the displacement behaviour. Le deplacement immiscible d'un fluide mouillant par un fluide non mouillant dans un milieu poreux desordonne a ete etudie dans la region capillaire, c'est-a-dire lorsque les forces capillaires sont dominantes, en utilisant le modele de percolation de l'invasion pour decrire le mecanisme de deplacement. Le milieu poreux est represente par un reseau bidimensionnel de capillaires interconnectes dont les rayons suivant une distribution de taille uniforme. Le desordre est assigne au milieu en tenant compte des probabilites d'occurrence des pores inaccessibles, ps, et des capillaires non conducteurs, pb. On a pu demontrer que le comportement dynamique du fluide de deplacement et la fraction des pores envahis dependaient du degre de desordre du milieu. Les resultats peuvent amener a une interpretation des effets du volume de pores morts sur la recuperation d'huile et le comportement du deplacement.