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The Time-Dependent Effect in Ultra High-Performance Concrete According to the Curing Methods.
Kwangmo Lim1, Kyongchul Kim1, Kyungtaek Koh1
1Korean Peninsula Infrastructure Special Committee, Korea Institute of Civil Engineering and Building Technology, Goyang-si 10223, Korea.
Materials (Basel, Switzerland)
|July 27, 2022
Summary
Ultra-high-performance concrete (UHPC) strength varies with curing. Steam curing yields superior long-term performance, crucial for managing precast bridge components and ensuring structural integrity.
Area of Science:
- Materials Science
- Civil Engineering
- Structural Engineering
Background:
- Ultra-high-performance concrete (UHPC) is vital for advanced structures like long-span bridges.
- Precast bridge girders often have varying ages due to different curing schedules.
- Understanding long-term UHPC performance under diverse conditions is essential for structural reliability.
Purpose of the Study:
- To compare the long-term performance of UHPC under different storage conditions after initial steam curing.
- To analyze the development of compressive strength, modulus of elasticity (MOE), and flexural strength up to 365 days.
- To develop prediction models for UHPC's long-term mechanical properties.
Main Methods:
- UHPC specimens were subjected to long-term storage under air, moist, and steam curing conditions after an initial 3-day steam cure.
- Compressive strength, MOE, and flexural strength were measured up to 365 days.
- Statistical analysis and prediction modeling were employed to evaluate performance trends.
Main Results:
- At 365 days, compressive strengths were 197 MPa (steam), 191 MPa (moist), and 169 MPa (air).
- Steam curing resulted in the highest strength development, while air curing showed the lowest.
- Flexural strength remained consistent across ages due to steel fiber reinforcement.
Conclusions:
- Curing conditions significantly impact the long-term mechanical properties of UHPC.
- Steam curing is optimal for maximizing UHPC strength development.
- The findings aid in managing strength variations in precast UHPC members for large-scale infrastructure projects.
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