Publications de Tamara Ghilardi

Analysis of Ballast Transport in the Event of Overflowing of the Drainage System on High Speed Lines

Giovanni De Cesare, Tamara Ghilardi, Mona Jafarnejad Chaghooshi, Elena Battisacco

The transport of ballast caused by the overflowing of longitudinal drains is a prime example of the interactions between the railway track and its environment. In such conditions, water flowing from the platform, along with debris, may drag the ballast off ...

2015

Analyse de risques pour les circulations ferroviaires d’un débordement de drainage sur ligne à grande vitesse (LGV)

Giovanni De Cesare, Tamara Ghilardi

RÉSUMÉ. – Suite à un incident survenu en 2000 sur la Ligne à Grande Vitesse (LGV) Paris‑Lyon sur la commune de Sarry dû à un emportement de ballast par débordement des eaux du drainage longitudinal de la plateforme ferroviaire, la SNCF a engagé en tant que ...

Edp Sciences S A2015

Period and amplitude of bedload pulses in a macro-rough channel

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

It is known that bedload fluctuates over time in steep rivers with wide grain size distributions, even under conditions of constant sediment feed and water discharge. Bedload fluctuations, which are a consequence of grain sorting, are periodic and are rela ...

American Geophysical Union2014

Sediment transport in steep channels with large roughness elements

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

Most sediment transport equations overestimate the bedload transport rate by several times when applied to mountain rivers. This is due to the fact that the presence of large relatively immobile boulders, which disrupt the flow, is generally not taken into ...

CRC Press/Balkema2014

Bulk velocity measurements by video analysis of dye tracer in a macro-rough channel

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

Steep mountain rivers have hydraulic and morphodynamic characteristics that hinder velocity measurements. The high spatial variability of hydraulic parameters, such as water depth (WD), river width and flow velocity, makes the choice of a representative cr ...

Institute of Physics2014

Bed load fluctuations in a steep channel

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

Bedload transport rate fluctuations have been observed over time in steep rivers and flumes with wide grain size distributions even under constant sediment feeding and water discharge. The observed bedload transport rate pulses are periodic and a consequen ...

American Geophysical Union2014

Sediment Transport and Flow Conditions in Steep Rivers with Large Immobile Boulders

Tamara Ghilardi

Recent flood events in Switzerland and across Europe pointed out several deficiencies in hazard assessment, planning, and prediction methods for flood risk mitigation. A good understanding of the dynamics of mountain rivers, grounded on a sound physical-ba ...

EPFL2013

Temporal evolution of bedload in a steep channel over a long duration experiment

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Tamara Ghilardi

Bedload fluctuations over time in steep rivers with wide grain size distributions have been observed, even under constant sediment feeding and water discharge. Observed bedload pulses are periodical and a consequence of grain sorting. Along with bedload, f ...

TPU2013

Experimental study on bedload pulses in a steep flume with boulders

Tamara Ghilardi

High-velocity plunging water jets, such as those formed by spillways of high-head dams, cause scour on the rock foundations. The scour process is the result of complex physical phenomena concerning the three media involved, namely, water, rock and air. Air ...

TPU2013