Title: Diagnostic Test for Load Rating of a Prestressed SCC Bridge
Author(s): E.S. Hernandez and J.J. Myers
Publication: Symposium Paper
Appears on pages(s): 11.1-11.16
Keywords: assessment of bridge structures, diagnostic load tests, long-term monitoring, service evaluation of bridges
Self-consolidating concrete (SCC) has emerged as an alternative to build stronger structures with longer service life. Despite the advantages of using SCC, there are some concerns related to its service performance. The effect of a smaller coarse aggregate size and larger paste content is of special interest. It is fundamental to monitor the response to service loads of infrastructure employing SCC in prestressed concrete members. Bridge A7957 was built employing normal-strength and high-strength self-consolidating concrete in its main supporting members. The diagnostic test protocol implemented in this research included static and dynamic tests and the calibration of refined finite element models simulating the static loads acting on the structure during the first series of diagnostic tests. The main objective of this study centered on (a) presenting a diagnostic test protocol using robust and reliable measurement devices (including noncontact laser technology) to record the bridge’s initial service response; and (b) obtaining the initial spans’ performance to evaluate and compare the SCC versus conventional concrete girders’ response when subjected to service loads. The initial response of the end spans (similar geometry and target compressive strength, but with girders fabricated using concrete of different rheology) was compared, and no significant difference was observed.