TIDC Research Thrust: Transportation infrastructure monitoring and assessment for enhanced life.
PI: Tzuyang Yu (UMass Lowell)
Co-PIs: Susan Faraji (UML), Changhoon Lee (WNEU), Moochul Shin (WNEU)
Institutions: University of Massachusetts Lowell (UML) and Western New England University (WNEU)
PI Email: Tzuyang_Yu@uml.edu
PI Phone: 978-934-2288
The problem we are trying to solve is the condition assessment of corroded prestressed concrete (PC) bridge girders in New England. The problem is important because that PC bridge girders are a critical component of highway bridges. Concrete spalling and prestressing strand corrosion not only cause losses in prestress but also lead to premature failures of PC bridges. We propose to
- Conduct multiplysical field inspection (using 3D photogrammetry, radar, impact-echo, and ultrasound) and to
- Develop an integrated assessment framework for predicting the level of structural damage and prestress losses for PC bridge girders. Fig. 1 provides an overview of the proposed research.
The objectives of this project are to:
- Develop a damage pattern database by conducting multiphysical nondestructive testing/evaluation including optical (3D photogrammetry), electromagnetic (radar), and mechanical (impact-echo, ultrasound) methods on field PC bridge girders.
- Develop structural degradation model/algorithms based on geometric change and material property change at the cross sectional level for condition assessment and decision-making.
- Develop an integrated assessment framework for predicting capacity reduction.
This project will enhance the transportation infrastructure durability as follows: Efficient condition assessment algorithm – The chemical-mechanical model proposed by this research will provide a theoretical, but computationally efficient algorithm for assessing the remaining structural strength of PC bridge girders. Data-driven decision-making – The vulnerability function for defining multiple damage states adopts the Bayesian framework, a data-driven method. The outcome can be customized improve the durability of PC bridges through effective structural repair.
December 30, 2019: We conducted laboratory accelerated corrosion test (ACT) on reinforced concrete (RC) cylinders (3” by 6”) for their pull-out test. Preliminary data for the pull-out test were developed.
March 31, 2020: We continued conducting the laboratory ACT on RC cylinders (3” by 6”) for their pull-out test. We corroded the RC cylinders with different levels of corrosion. 100%, 75%, and 50% corrosion RC cylinders were carried out for this project. We monitored the environmental condition (e.g., temperature and pH value) inside the corrosion reactor during the course of each artificial corrosion test to understand what is happening during the ACT experiment.
The experimental relationship between the initial current and the corrosion time for three RC cylinders was developed. In addition, we also continued conducting the laboratory SAR imaging of RC cylinders in order to develop condition assessment criteria for corroded concrete bridges.