Improved Finite Element Model Updating of a Highway Viaduct Using Acceleration and Strain Data.

Area of Science:

• Structural Engineering
• Computational Mechanics
• Bridge Engineering

Background:

• Finite Element Model Updating (FEMU) for bridges often relies on acceleration data due to cost and convenience.
• Strain and displacement-based FEMU are less common, leading to a gap in comprehensive studies incorporating strain measurements.

Purpose of the Study:

• To perform and compare strain- and acceleration-based FEMU on a multi-span concrete highway viaduct.
• To evaluate the effectiveness of residual minimization versus the error-domain model falsification (EDMF) methodology in FEMU.

Main Methods:

• Strain-based FEMU utilized mid-span strains under heavy vehicles.
• Acceleration-based FEMU used frequencies and mode shapes.
• Analyses adjusted Young's modulus factors for structural elements using residual minimization and EDMF.

Main Results:

• Strain- and frequency-based FEMU indicated a ~20% increase in superstructure design stiffness.
• EDMF provided more sensible updated variables by incorporating strain data alongside acceleration data.
• EDMF resulted in an overestimated design stiffness of 25-50% for internal main girders.

Conclusions:

• The error-domain model falsification (EDMF) methodology offers advantages over residual minimization for FEMU.
• Integrating strain measurements alongside acceleration data improves the accuracy and sensibility of updated finite element models for bridges.
• Further refinement of EDMF may be needed to avoid overestimation of stiffness in specific structural components.