Flexural properties of load-holding reinforced concrete beams strengthened with textile-reinforced concrete under a chloride dry–wet cycle

Shiping Yin,Mingwang Na,Yulin Yu

doi:10.1177/1558925019845902

Abstract

To study the reinforcement effect of textile-reinforced concrete (TRC) on concrete structures in a marine environment, a four-point bending loading method was used for graded loading to analyze the influence of the dry–wet cycle number, the reinforcement method, and chopped fiber addition on the flexural properties of load-holding reinforced concrete beams reinforced with textile-reinforced concrete. The results show that with the increase of dry–wet cycle numbers, the crack width and deflection of beams develop faster and the bearing capacity decreases. The performance of the prefabricated textile-reinforced concrete plate is close to that of a cast-in-place textile-reinforced concrete in limiting crack, bearing capacity, and deflection deformation. The addition of chopped fibers in fine-grained concrete can improve the reinforcement effect of textile-reinforced concrete. Based on the experimental results and referring to the relevant design codes and literature, the calculation formula of the bearing capacity of TRC-strengthened beam with a secondary load is established, and the calculated values are in good agreement with the actual values.

Highlights

Damage of concrete structures caused by insufficient durability is very common, especially the durability problem of marine concrete structures, which shows a yearly increasing trend
The results of Yin et al.[13] and Sheng et al.[14] showed that the bonding performance between textile-reinforced concrete (TRC) and old concrete would be affected by the coupling effect of load and the dry–wet cycle with chloride; TRC still played a better role in improving the crack development and fatigue life of beams
The overall change range is lower; TRC is suitable for reinforcing damaged beams under a chloride environment

Summary

Introduction

Damage of concrete structures caused by insufficient durability is very common, especially the durability problem of marine concrete structures, which shows a yearly increasing trend. The results from Verbruggen et al.[9] showed that the TRC reinforcement layer had good crack bridging ability and its application on the full width of a beam was beneficial to bearing capacity improvement and crack width limitation. The results of Yin et al.[13] and Sheng et al.[14] showed that the bonding performance between TRC and old concrete would be affected by the coupling effect of load and the dry–wet cycle with chloride; TRC still played a better role in improving the crack development and fatigue life of beams. The crack width was measured via a crack width tester produced by Beijing Earth Long Science and Technology Co., Ltd., with an accuracy of 0.02 mm

Experimental results and analysis

H2 H3 H4 H5 H6

Conclusion