Fatigue Characteristics of Double Damage Reinforced Prestressed Hollow Slab Beams under Freeze-Thaw Cycle Erosion
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Published:2021-08-21
Issue:16
Volume:11
Page:7692
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ISSN:2076-3417
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Container-title:Applied Sciences
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language:en
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Short-container-title:Applied Sciences
Author:
Zheng Yuanxun,Liu Jiaqi,Guo Pan,Gan Chao
Abstract
A bridge structure is subjected to different external loads and environmental effects during its operation, which results in different types and degrees of damage to the structure during its service life. Reinforcement is often required to maintain regular operation and extend its service life. However, a reinforced bridge structure continues to be subjected to vehicle loads and environmental erosion. Therefore, research on the durability deterioration mechanisms and fatigue life decay of reinforced structures is key to ensuring the long service lives of bridge structures. To study the influence of freeze–thaw cycle erosion on the basic mechanical properties and fatigue characteristics of a bridge structure and a strengthened structure, 2 m long prestressed hollow slab beams were designed and fabricated based on the principle of a similarity ratio and subsequently pre-cracked by fatigue failure. The prestressed hollow slab beams were strengthened after fatigue damage by two methods: pasting steel plates and pasting carbon fiber cloths. After this, a freeze–thaw cycle test was conducted to study the dynamic and static mechanical index changes and the attenuation of the fatigue characteristics of the prestressed strengthened hollow slab beams under freeze–thaw cycle erosion. Meanwhile, a numerical model for reinforced structures was established based on the ABAQUS software to study the mechanisms governing the attenuation of the fatigue life of the prestressed hollow slab beams with different freeze–thaw cycles. The results showed that the deflections and strains observed for the two methods were less than those prior to reinforcement. For instance, the deflection in the span decreased by 14–15%, and the compressive strain decreased by 5.2% to 6%. Under the fatigue load, the prestressed hollow slab beams strengthened by the two methods could withstand a fatigue load cycle of 2 million, and the reinforced components exhibited good fatigue resistance. Under cyclic erosion and fatigue loading, the deflections and strains in the reinforced prestressed hollow slab beams were increased by varying degrees, such as a 30–40% increase in the tensile strain and a 65–70% increase in the span. The fatigue life of the reinforced hollow slab beams decreased with the increasing number of freeze–thaw cycles, and the decay rate of the fatigue life was accelerated.
Funder
National Natural Science Foundation of China
Key Research and Development and Promotion Special Project of Henan Province in 2020
Subject
Fluid Flow and Transfer Processes,Computer Science Applications,Process Chemistry and Technology,General Engineering,Instrumentation,General Materials Science
Reference44 articles.
1. The significance of critical degrees of saturation at freezing of porous and brittle materials;Fagerlund,1975
2. Research on influence of air content on frost resistance of fly ash concrete;Ban;J. Water Resour. Water Eng.,2014
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