Advances in the study of soil-structure interaction effects on the dynamic response of piled structures

[EN]This Ph. D. thesis presents a simple and stable procedure for the estimation of periods and dampings of pile shear buildings taking soil-structure interaction into account. The coupled-system response is obtained by using a substructuring model. A boundary element-finite element coupling formulation is used to compute impedances and kinematic interaction factors of the pile group configurations under investigation. The proposed procedure is applied to perform parametric analyses to determine the influence of the main parameters of soil-structure interaction problems on the dynamic response of the superstructure. The scope of this thesis also encompasses the study of foundations including battered piles.

Dynamic structure-soil-structure interaction between nearby piled buildings under seismic excitation by BEM-FEM model

[EN]The dynamic throug-soil interaction between nearby pile supported structures in a viscoelastic half-space, under incident S and Rayleigh waves, is numerically studied. To this end, a three-dimensional viscoelastic BEM-FEM formulation for the dynamic analysis of piles and pile groups in the frequency domain is used, where soil is modelled by BEM and piles are simulated by one-dimensional finite elements as Bernouilli beams.

Structure-soil-structure interaction effects on the dynamic response of piled structures under obliquely-incident seismic shear waves.

[EN] This work studies the structure-soil-structure interaction (SSSI) effects on the dynamic response of nearby piled structures under obliquely-incident shear waves. For this purpose, a three-dimensional, frequency-domain, coupled boundary element-finite (BEM-FEM) model is used to analyse the response of configuration of three buildings aligned parallel to the horizontal component of the wave propagation direction.

Effects of soil-structure interaction on the dynamic properties and seismic response of piled structures.

[EN]This paper presents a simple and stable procedure for the estimation of periods and dampings of piled shear buildings taking soil-structure interaction into account. A substructuring methodology that incluedes the three-dimensional character of the foundations is used.

Soil-structure interaction during tunnelling in urban area: observations and 3D numerical modelling

This work illustrates a soil-tunnel-structure interaction study performed by an integrated,geotechnical and structural,approach based on 3D finite element analyses and validated against experimental observations.The study aims at analysing the response of reinforced concrete framed buildings on discrete foundations in interaction with metro lines.It refers to the case of the twin tunnels of the Milan (Italy) metro line 5,recently built in coarse grained materials using EPB machines,for which subsidence measurements collected along ground and building sections during tunnelling were available.Settlements measured under freefield conditions are firstly back interpreted using Gaussian empirical predictions. Then,the in situ measurements’ analysis is extended to include the evolving response of a 9 storey reinforced concrete building while being undercrossed by the metro line.In the finite element study,the soil mechanical behaviour is described using an advanced constitutive model. This latter,when combined with a proper simulation of the excavation process, proves to realistically reproduce the subsidence profiles under free field conditions and to capture the interaction phenomena occurring between the twin tunnels during the excavation. Furthermore, when the numerical model is extended to include the building, schematised in a detailed manner, the results are in good agreement with the monitoring data for different stages of the twin tunnelling. Thus, they indirectly confirm the satisfactory performance of the adopted numerical approach which also allows a direct evaluation of the structural response as an outcome of the analysis. Further analyses are also carried out modelling the building with different levels of detail. The results highlight that, in this case, the simplified approach based on the equivalent plate schematisation is inadequate to capture the real tunnelling induced displacement field. The overall behaviour of the system proves to be mainly influenced by the buried portion of the building which plays an essential role in the interaction mechanism, due to its high stiffness.

A new multimodality technique accurately maps the primary lymphatic landing sites of the bladder

Pathoanatomic studies have failed to map accurately the primary lymphatic landing sites of the urinary bladder.

Fluorescent Chrysotile From Sterling Hill, New Jersey

Minerals of the serpentine group, notably chrysotile and to a lesser extent lizardite, are widely present at both Franklin and Sterling Hill. They are late-stage hydrous magnesium silicate minerals that formed by hydrothermal alteration of earlier species, among them willemite and tephroite, and are also common components of hydrothermal veins cutting the ore bodies and the enclosing marble (Dunn, 1995). Although long recognized in the area (Fowler, 1825), local serpentine was not documented as a fluorescent mineral until 2004, when a brief description of a fluorescent serpentine from Franklin appeared in The Picking Table (Cianciulli, 2004). In the present paper, we describe additional examples of fluorescent serpentine, most from Sterling Hill.