Load Distribution of a Prestressed Self-Consolidating Concrete Bridge

Eli S Hernandez,John J Myers

doi:10.3389/fbuil.2019.00096

Abstract

Bridge A7957 is the first Missouri Department of Transportation (MoDOT) large-scale project using self-consolidating concrete (SCC) and high-strength self-consolidating concrete (HS-SCC). The objective of this research was to monitor the initial in-service behavior of the precast-prestressed concrete primary elements of Bridge A7957 and to obtain the load distribution of the bridge using field and finite element models (FEM) data. An initial series of diagnostic load tests was conducted on the bridge superstructure. Embedded sensors recorded strain variations at different section of the instrumented girders for different load configurations. An automated total station (ATS) collected the vertical deflection of the girders at several locations during the application of different test loads. The load distribution for moment was obtained experimentally (using deflection and strain data), FEMs, and using the AASHTO LRFD Bridge Design Specifications. The distribution factors for moment estimated with the AASHTO LRFD equations resulted in larger values compared to field test and FEM results. No difference was observed between the response of the SCC and conventional concrete members during the first series of field load tests.

Highlights

During the last two decades, self-consolidating concrete (SCC) and high-strength self-consolidating consolidating concrete (HS-SCC) have been successfully implemented in infrastructure projects due to its effective characteristics (Ouchi et al, 2003; McSaveney et al, 2011; Keske et al, 2014; Hernandez and Myers, 2015b)
In the case of Bridge A7957, the experimental distribution factor obtained for spans 1 and 3 (Tables 5, 6) were comparable showing that this parameter is independent of the type of material employed to fabricate the prestressed concrete girders
The maximum difference observed was close to 4%, suggesting that the calibrated finite element models (FEM) can reproduce the behavior of the bridge with an acceptable level of accuracy for the level of load applied during the load tests

Summary

Introduction

During the last two decades, self-consolidating concrete (SCC) and high-strength self-consolidating consolidating concrete (HS-SCC) have been successfully implemented in infrastructure projects due to its effective characteristics (Ouchi et al, 2003; McSaveney et al, 2011; Keske et al, 2014; Hernandez and Myers, 2015b). HS-SCC brings an enhanced flexural performance to conventional SCC because of its greater compressive strength. This stronger flexural characteristic brings the possibility to reduce the number of main carrying members and interior supports of bridge structures. It is essential to monitor the in-service response of full-scale highway infrastructure utilizing self-consolidating and high-strength self-consolidating precast-prestressed concrete members

Objectives

Results

Conclusion