Comportement longitudinal en flexion d’une conduite enterrée dans un remblai hétérogène

Abstract

Longitudinal flexural behavior of a pipe buried in an heterogeneous embankment Abstract A simple model which describes the soil-pipe interaction and accounts for the longitudinal soil variation has been developed. It is used for the analysis of the static response of a section of a buried sewer. A probabilistic analysis (Monte-Carlo method) enabling to quantify the influence of spatial variability of the geomechanical characteristics of the soil makes possible to study the parameters which can influence and drive the longitudinal response of a section of sewer. The system response is complex, soil-structure interaction depending on three different stiffnesses : soil stiffness, pipe components stiffness and joints stiffness. Various analysis have been performed to identify the parameters whose influence is the larger. A specific attention has been devoted to the fluctuation scale of the soil properties and to the stiffness of joints.

Longitudinal variability of soils and structural response of sewer networks

“…From a parametric study [31,32] it was concluded that, if variation of k can be interpreted like resulting from the space variability of the soil properties, one will not have to stick too exclusively to the values of this parameter, since an uncertainty of about 100% can result from the simple choice of the k model which is used. Reversely, once a k model is (more or less arbitrary) given, the effects of the space variations of k(x) can be studied and quantitative results can be drawn.…”

Spatial variations in soil properties and their influence on structural reliability

“…Building such a model is justified by the fact that a level 3 model must have a comparable level of sophistication regarding soil description or regarding structural behaviour. The fact that a large number of failures in sewer systems are induced by soil heterogeneity has justified this study (Elachachi et al 2004a). The model is analysed using Monte-Carlo simulations.…”

“…The stiffness of the springs is given by k, which links pressure p to settlement s(p(x) = k(x) · s(x)) and which corresponds to the subgrade reaction of the soil (in N/m 3 ). The value of this parameter k depends on the soil Young modulus and on the geometry of the structure (mainly its width), it is derived from common semi-empirical expressions (Elachachi et al 2004a).…”

Variability of subgrade soil rigidity and its effects on the roughness of flexible pavements: a probabilistic approach

“…Using a statistical analysis of the digital simulation results, the risks of exceeding critical values (stresses, displacement) are then estimated to assess structure performance. This approach allows the study of the behaviour of the longitudinal direction of the pavement based on the variability of the subgrade soil properties in terms of the redistribution of forces and displacements of the pavement [4,7]. Pavement deformation depends, among other things, on the rigidity ratio between the subgrade soil and pavement structure [1,2].…”