Bridge Deck Runoff: Water Quality Analysis and BMP Effectiveness

INE/AUTC 10.0

CONDITION MONITORING OF A LIGHTLY REINFORCED CONCRETE BEAM BY DYNAMIC MEASUREMENTS

The paper deals with the assessment of damage in a lightly reinforced concrete beam using the measured values of the first natural frequency. The aim of the presented laboratory experiment was the experimental investigation of the relationship between the degree of cracking and the first natural frequency under defined deterioration conditions. As a result of the test, a definite relationship between the investigated parameters could be demonstrated

Seismic fragility analysis of reinforced concrete bridges with chloride induced corrosion subjected to spatially varying ground motion

This paper studies the time-dependent seismic fragility of reinforced concrete bridges with chloride induced corrosion under spatially varying ground motions. The time-varying characteristic of the chloride corrosion current density and the uncertainties related to the structural, material and corrosion parameters are both considered in the probabilistic finite element modeling of the example RC bridge at different time steps during its life-cycle. Spatially varying ground motions at different bridge supports are stochastically simulated and used as inputs in the fragility analysis. Seismic fragility curves of the corroded RC bridge at different time steps are generated using the probabilistic seismic demand analysis (PSDA) method. Numerical results indicate that both chloride induced corrosion and ground motion spatial variations have a significant effect on the bridge structural seismic fragility. As compared to the intact bridge, the mean peak ground accelerations (PGAs) of the fragility curves of the RC bridge decrease by approximately 40% after 90 years since the initiation of corrosion. Moreover, the effect of ground motion spatial variations changes along with the process of chloride induced corrosion owing to the structural stiffness degradation. Neglecting seismic ground motion spatial variations may not lead to an accurate estimation of the lifetime seismic fragility of RC bridges with chloride induced corrosion

Durability of bond of EBR CFRP laminates to concrete under real-time field exposure and laboratory accelerated ageing

The durability of bond between carbon fibre-reinforced polymer (CFRP) laminates and concrete with the externally bonded reinforcement (EBR) technique was investigated under real-time field exposure (RTFE) and accelerated ageing. The experimental program, over two years, includes four outdoor environments inducing carbonation, freeze–thaw attack, extreme temperatures, and airborne chlorides from the ocean. A laboratory environment (20 ◦C/55% RH) was used as reference environment. Additionally, a water-immersion environment (20 ◦C) was also considered. Relatively low values of bond degradation were observed, where the maximum pullout force varied between − 4 % and +16 % under RTFE, while on water–immersed specimens, the maximum pullout force decreased by ~8 %.This work was carried out in the scope of the project FRPLongDur POCI-01-0145-FEDER-016900 (FCT PTDC/ECM-EST/1282/2014) and DURABLE-FRP (PTDC/ECI-EGC/4609/2020) funded by national funds through the Foundation for Science and Technology (FCT) and co-financed by the European Fund of the Regional Development (FEDER) through the Operational Program for Competitiveness and Internationalization (POCI) and the Lisbon Regional Operational Program and, was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020, and under the Associate Laboratory Advanced Production and Intelligent Systems ARISE under reference LA/P/0112/2020. The first author wishes also to acknowledge the grant SFRH/BD/131259/2017 provided by Fundação para a Ciência e a Tecnologia (FCT)