Page 36 - DOUCE HYDRO 2013

36
Preloaded
Spring dampers
Preloaded Spring Damper (PSD) is a unit designed to dissipate seismic energy on structures such as
bridges.The PSD reduces longitudinal and transversal displacement of the deck. Douce-Hydro/Jarret Structures
can provide two types of PSD: working in tension/compression, or acting only in compression. Douce-Hydro/
Jarret Structures can install the PSD compression type longitudinally between the deck and the abutment,
or install a PSD tension/compression unit in transversal position between the deck and the pier structure.
The PSD acts as a shear key which has the possibility to regenerate itself automatically after a dynamic event.
The seismic energy is dissipated in the PSD unit instead of being displaced in a steel or concrete structure.
According to their position, these devices can accommodate transversal and longitudinal seismic displacement,
and at the same time take into account longitudinal displacement such as creep shrinkage and thermal
expansion or contraction.
A
Transversal PSD on the Deck. (F= 2200 kN, Stroke = 50mm)
Motorway bridge A51,Viaduct of Monestier in France.
Transversal PSD (F= 2200 kN)
St. André Viaduc,
Fréjus in France
Longitudinal PSD on abutment
(F = 2500 kN, Stroke = 50mm)
High Speed railroad viaduct
of Epenottes, France.
B R I D G E S