Experimental study on thermal performance of ultra-high performance concrete with coarse aggregates at high temperature

The Ultra High Performance Concrete (UHPC) is a very promising material suitable for application in special structures. However, the knowledge of performance of this relatively new material is rather limited. The exceptional mechanical properties of UHPC allow for a modification of the design rules, which are applicable in ordinary or high strength concrete. This paper deals in more detail with impact of thermal stress on bond properties between prestressing strands and UHPC and an influence of high temperature to final material properties of different UHPC mixtures. Specimens in the first experimental part were subjected to the cycling freeze-thaw testing. The relationship between bond behavior of both type of material (UHPC and ordinary concrete) and effect of cycling freeze-thaw tests was investigated. The second part of experimental work was focused on mechanical properties of UHPC exposure to the high temperature (Tmax = 200°C to Tmax = 1000°C). Tested mechanical properties were compressive and flexural strengths, the fracture properties will be presented in the next paper. The obtained experimental data serve as a basis for further systematic experimental verification and more accurate information about the significantly higher material properties of UHP(FR)C and its behavior in extreme conditions.

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Combined curing as a novel approach to improve resistance of ultra-high performance concrete to explosive spalling under high temperature and its mechanical properties

Cement and Concrete Research ◽

10.1016/j.cemconres.2018.04.011 ◽

2018 ◽

Vol 109 ◽

pp. 147-158 ◽

Cited By ~ 14

Author(s):

Gai-Fei Peng ◽

Xu-Jing Niu ◽

Ya-Jie Shang ◽

Deng-Ping Zhang ◽

Xi-Wang Chen ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

High Performance ◽

High Performance Concrete ◽

Ultra High Performance Concrete ◽

Explosive Spalling ◽

Novel Approach

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Effect of Fiber on Residual Strength and High Temperature Burst Performance of Ultra High Performance Concrete

Forest Chemicals Review ◽

10.17762/jfcr.vi.203 ◽

2021 ◽

pp. 224-231

Author(s):

Huijie Shang, Qianqian Peng

Keyword(s):

Compressive Strength ◽

High Temperature ◽

Mass Loss ◽

Ultrasonic Wave ◽

Wave Velocity ◽

Residual Strength ◽

High Performance ◽

High Performance Concrete ◽

Ultra High Performance Concrete ◽

Burst Performance

In this paper, the effects of fiber on the residual strength and high temperature burst performance of ultra-high performance concrete are studied. This paper analyzes the performance change law of concrete after high temperature from three aspects: mass loss, ultrasonic wave velocity and compressive strength. The results show that with the increase of heating temperature, the mass loss increases and the ultrasonic wave velocity decreases. The compressive strength of concrete increases gradually before 300 ℃ and decreases gradually after 400 ℃. Mixing PVA fiber and steel fiber can not only improve the burst resistance of ultra-high performance concrete at high temperature, but also have high residual strength. This paper discusses the high temperature burst mechanism of ultra-high performance concrete, which is caused by the change of steam pressure and microstructure.

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