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The longitudinal variation of soil properties has a major influence for many types of structure, including pavements, buried pipes, raft foundations and railways, as it induces stresses and/or displacements that cannot be predicted when assuming soil homogeneity. A set of simple numerical models has been developed to describe how soil–structure interaction can be influenced by soil variability. These models include: (a) a description of the soil spatial variability, within the frame of geostatistics, where the correlation length of soil properties is the main parameter; and (b) a mechanical description of the soil–structure interaction, which depends on the structure resting on the ground. There are some differences between a (more or less) rigid raft on piles, a set of buried pipes with (more or less) flexible connections and a hyperstatic beam, but the basic principles of mechanics are similar in all these cases. Several very general conclusion are drawn. (a) Soil heterogeneity induces effects (differential settlements, bending moments, stresses and possible cracking) that cannot be predicted if homogeneity is assumed. (b) The magnitude of the induced stresses depends on three factors: the magnitude of the soil variability (i.e. its coefficient of variation); a soil–structure stiffness ratio (in some cases, where the mechanics are more complex, one can consider two stiffness ratios, as in buried pipes for example, when one has to account for the flexibility both of the pipes and of the connections); a soil–structure length ratio, which combines the soil fluctuation scale and a structural characteristic length (distance between supports, buried pipe length, etc). In all cases, a worst value, corresponding to the value leading (from a statistical point of view) to the (statistically) largest effects in the structure, can be found. The principal benefit of such an approach is to provide some new approaches for better considering phenomena such as the geometrical irregularities in the longitudinal profile of pavements or during the control of soil compaction of sewer trench filling. This kind of approach can also give experts new tools for better calibration of safety in soil–structure interaction problems, when the soil variability is an influential parameter. Some practical conclusions are drawn in this direction.

During an excavation in Tours, descriptive and statistical methods allying geotechnical and archaeological data, have been organized for the use of the PANDA penetrometer. Knowing that the alluvion upper part forms the soil, the first aim is to distinguish the archaeological deposit from it. This target can be reached without too many difficulties and the penetrometer's data can be confirmed by geo-endoscopy. The results enable us to set out a grid in order to reveal the archaeological deposit's thickness and the alluvion upper part's relief on the town scale. A further second aim is to characterize a soil pierced by the penetrometer. The current work is about defining a scale interpretation which is compatible between the archaeological one and the geotecnical one. So as to define a scale, the hypothesis kept is that the intensity, of an often human activity and occasionally of natural origin, is revealed by the stratigraphical diversity. With the elaboration of a frame of reference linked to the resistance of the different kind of archaeological layers on one hand, and with the study of the recorded signal variation intensity on the other hand, we can subdivide a whole several meter stratification into slices corresponding to a complexity index of the activity rate. The analysis of the penetrometrical measures spatial structuration enables to distinguish a random agitation, the result of measure's noise, from a structured agitation which reveals the characteristics of the soil. Thanks to this analysis, each measures série is given a quality index. An other method of investigation by geo-endoscopy 's analysis will show us caracterization more fine of these slices., L'utilisation du pénétromètre PANDA à l'occasion d'une fouille à Tours a suscité la mise en place de méthodes descriptives et statistiques liant données géotechniques et archéologiques. Un premier objectif consiste à distinguer le dépôt archéologique du toit des alluvions qui forment le sol géologique. Cet objectif se révèle accessible sans trop de difficultés et les données du pénétromètre peuvent être confirmées par géo-endoscopie. Les résultats obtenus ouvrent la possibilité de réaliser un maillage pour restituer l'épaisseur du dépôt archéologique et le modelé du toit des alluvions à l'échelle de la ville. Un deuxième objectif, plus lointain, est de caractériser le sol traversé par le pénétromètre. Les travaux en cours portent sur la définition d'une échelle d'interprétation compatible avec celles de l'archéologie et de la géotechnique. Pour définir cette échelle, l'hypothèse retenue est que la variété stratigraphique reflète l'intensité de l'activité le plus souvent humaine, parfois d'origine naturelle. Par la construction d'un référentiel lié à la résistance des différents types de couches archéologiques et par l'étude de l'intensité de la variation du signal enregistré, il est envisagé de subdiviser l'ensemble d'une stratification de plusieurs mètres en tranches affectées d'un indice de complexité reflétant le taux d'activité. L'analyse de la structuration spatiale des mesures pénétrométriques permet aussi de faire la part de l'agitation aléatoire, résultant de bruits de mesures, d'une agitation structurée, révélatrice des propriétés du milieu traversé. Elle permetd'attacher un indice de qualité à chaque série de mesures. Une caractérisation plus fine de ces tranches nécessitera une autre méthoded'investigation par analyse géo-endosco- pique., Galinié Henri, Laurent Amélie, Rodier Xavier, Breysse Denys, Niandou Halilou, Breul Pierre. Utilisation du pénétrométre dynamique de type Panda en milieu urbain pour l'évaluation et la caractérisation du dépôt archéologique.. In: Revue d'Archéométrie, n°27, 2003. pp. 15-26.

Physiologic stress associated with illness and hospitalization is known to result in gastrointestinal ulceration, especially among the critically ill. The complication of this stress-related mucosal disease could be prevented with appropriate application of pharmacologic prophylaxis. Vigilance by the nursing staff is required to properly detect and manage the condition.