Horizontal bridge-soil interaction assessment by dynamic testing |
| |
Authors: | J R Casas |
| |
Institution: | (1) Civil Engineering Department, Technical University of Catalunya, 08034 Barcelona, Spain |
| |
Abstract: | This paper presents a methodology to assess the real longitudinal stiffness of a bridge including the foundation-soil interaction.
The method is based on a dynamic test of the bridge complemented by structural identification. The experimentally obtained
natural frequencies of the bridge in the horizontal and vertical planes are used to derive, via a parameter identification
procedure and a dynamic model of the bridge, the most approximate values of the Winkler coefficients simulating the interaction
of foundation with ground. The theoretical background of the procedure is first presented and then demonstrated on a prestressed
concrete highway bridge with a total length of 2040 m (normal span length of 40 m). The bridge is located near the sea coast,
and large variations in the soil properties were observed between the piers. As a consequence, it was not possible to assess
in a reliable way the actual global stiffness of this bridge (due to the interaction of deck, piers, abutments and foundations)
in front of horizontal forces (vehicle braking, earthquake, wind and so on) based on the results of the geotechnical survey.
The dynamic excitation in the longitudinal direction was easily achieved by means of controlled vehicle braking at different
points on the bridge. The results show the feasibility of using dynamic testing with vehicle braking as excitation to deduce
the correct behavior of the bridge under the effect of horizontal loads. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|