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Structural Monitoring and Maintenance Volume 10, Number 2, June 2023 , pages 155-174 DOI: https://doi.org/10.12989/smm.2023.10.2.155 |
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Monitoring of bridge overlay using shrinkage-modified high performance concrete based on strain and moisture evolution |
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Yifeng Ling, Gilson Lomboy, Zhi Ge and Kejin Wang
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| Abstract | ||
| High performance concrete (HPC) has been extensively used in thin overlay for repair purpose due to its excellent strength and durability. This paper presents an experiment, where the sensor-instrumented HPC overlays have been followed by dynamic strain and moisture content monitoring for 1 year, under normal traffic. The vibrating wire and soil moisture sensors were embedded in overlay before construction. Four given HPC mixes (2 original mixes and their shrinkage-modified mixes) were used for overlays to contrast the strain and moisture results. A calibration method to accurately measure the moisture content for a given concrete mixture using soil moisture sensor was established. The monitoring results indicated that the modified mixes performed much better than the original mixes in shrinkage cracking control. Weather condition and concrete maturity at early age greatly affected the strain in concrete. The strain in HPC overlay was primarily in longitudinal direction, leading to transverse cracks. Additionally, the most moisture loss in concrete occurred at early age. Its rate was very dependent on weather. After one year, cracking survey was carried out by vision to verify the strain direction and no cracks observed in shrinkage modified mixes. | ||
| Key Words | ||
| dynamic moisture content; high performance concrete (HPC); overlay condition monitoring; soil moisture sensor; strain direction | ||
| Address | ||
| Yifeng Ling and Zhi Ge: Department of Qilu Transportation, Shandong University, Jinan 250002, Shandong Province, PR China Gilson Lomboy: Department of Civil and Environmental Engineering, Rowan University, 201 Mullica Hill Road, Glassboro, NJ 08028, USA Kejin Wang: Department of Civil, Construction and Environmental Engineering, Iowa State University, Ames, IA, 50011, USA | ||
