1. Study on early shrinkage and cracking of slab in UHPC light-weight composite deck based on ambient temperature and humidity effects.
- Author
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Wang, Cong, Yang, Yibo, Zhu, Jinsong, Wang, Yanlei, and Ding, Jingnan
- Subjects
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BRIDGE design & construction , *STEEL-concrete composites , *TEMPERATURE effect , *STRAINS & stresses (Mechanics) , *HIGH strength concrete , *CONSTRUCTION slabs , *COMPOSITE construction - Abstract
This study investigates the early performance and potential issues of ultra-high-performance concrete (UHPC) light-weight composite decks (LCBDs) used in municipal highway bridge design. The major objective of this research was to understand the complex evolution of temperature and humidity within immature UHPC thin layers, which can lead to deformation and secondary stress, potentially causing cracks and threatening the long-term applicability and safety of steel-concrete composite bridges. Understanding of the mechanism of this process will be the basis for subsequent work. The early performance of UHPC with ordinary concrete is compared. Besides, discussions are conducted on the basic thermal conductivity theory of three-dimensional porous media and the hydration mechanism of cement-based materials that are appropriate for early-stage UHPC. Subsequently, a refined thermo-mechanical coupling analysis method for steel-UHPC LCBD was proposed, implemented using ABAQUS, and validated through a UHPC composite beam test. This method was applied to calculate the early shrinkage of the UHPC layer in a steel-UHPC LCBD and evaluate the risk of cracking in an actual bridge expansion project, providing a rationality evaluation of a bridge design and its construction procedure. • An approach for early shrinkage and crack assessment of UHPC light-weight composite bridge decks (LCBD) is suggested. • The aforementioned method is validated by an existing experiment and data therein. • Parametric analysis based on varying curing conditions of the composite beam is performed. • The design of the upper deck is evaluated, and construction & maintenance tips for a certain bridge project are proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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