Keynote Speaker

Stefano Pagliara

Professor of Hydraulic Construction,
University of Pisa, Italy

Title of the Talk : “Hydraulic Behaviour of In-Stream Low Head Structures for River Restoration“

Abstract:

Small hydraulic structures such In-stream grade-control structures are used to protect riverbanks, and to improve and rebuild aquatic habitats. In the last decades many of these structures have been analyzed. Among the others, block ramp, cross vane, j-hook, chevron type and wood logs.

All these structures have a great value for river restoration. The paper will show some experimental studies that highlight the behaviour of these structures.

Fig.1 basin of a block ramp

The lecture will show the study of the scour phenomena and morphologies downstream of these structures. Experiments have been conducted in clear-water conditions. The results showed the important effect on the position in the channel (straight or curved) and the effect of the structures angles and slopes.

One important parameter is the protection of the side banks from the scour process. Useful empirical relationships have been proposed in order to evaluate the main features of the scour geometry for all the tested situation.

Fig.2 j-hook in ba bend channel

A comparison between different structures type has been done in order to show pro and contras of each geometry.

Among the analyzed structures some are made of wood. This is an important advance in the construction of these small structures due to the low environmental impact and of their ecological use.

Fig.3 wood log frame

About the Speaker

Stefano Pagliara is full professor of Hydraulic structures at the University of Pisa, Italy. He has been Fulbright researcher at the University of Illinois at Urbana/Champaign and researcher for the Japanese government at the Public Work Research Institute at Tsukuba – Ibaraki – Japan. He has been Visiting Professor at ETH Zurich (CH). He is author of 300 papers mainly in international journals, board member of IAHR and chairman of the Hydraulic structure committee of IAHR. His research interests are on hydraulic structures, jet scour, river restoration, urban drainage and flood risk and mitigation.