Study On Compressive Properties Of Small Eccentric RC Columns Strengthened With TRC Under Chloride Corrosion Environment

Textile reinforced concrete(TRC)is a new kind of composite material which is made up of textile and high performance concrete.In terms of reinforcement,TRC not only has some of the advantages of FRP,but also has the following advantages: Firstly,the use of high performance concrete can improve the coordination between the reinforced layer and the concrete foundation,and can resist the high temperature environment.Secondly,the high performance concrete with self-sealing property,antisegregation,high fluidity,can repair cracks on the surface of damaged structure well,and can make the reinforced component add a layer of anti-corrosion protection layer.In this paper,based on the special subject of scientific frontiers research subject of China University of Mining and Technology-“The degradation mechanism of RC eccentric columns strengthened with TRC under the marine dry-wet environment”,the mechanical properties of small eccentric RC columns reinforced with TRC under chloride dry-wet cycle were studied.The specific contents were summarized as follows:(1)This paper studied the mechanical properties of small eccentric RC columns reinforced with TRC in consideration of textile layers,slenderness ratio,steel ratio,PVA short fiber content,chloride dry-wet cycles,coupling effect of load and chloride environment.The results showed that TRC had good effect on the reinforcement of small eccentric columns under chloride dry-wet environment.With the number of TRC layers increased,the reinforcement effect was improved,but when the number of TRC layers were increased to 4,the reinforcement effect was slowing down.The reduction of slenderness ratio was helpful to improve the bearing capacity of reinforced column.With the increase of steel ratio and PVA short cut fiber,the reinforcement effect of TRC could be improved.With the increase of the number of wet-dry cycles,the reinforcement effect of TRC had a decreasing trend.The coupling effect of load and chloride environment on the compressive properties of columns strengthened with TRC was more obvious,and with the load increased,the damage would increase further.(2)In the study of the compressive behavior of small eccentric corroded RC columns strengthened with TRC,the effects of different textile layers and the comparison with the no corrosion RC columns were considered.The results showed that the brittle characteristic of the corroded column was more significant than that of the no corrosion column,and the strengthening effect of TRC was good,which provided a resistance to chloride corrosion and confinement effect for the columns strengthened with TRC.The bearing capacity of corroded columns strengthened with one TRC layer increased obviously,but with the number of TRC layers increase,the increase of bearing capacity was slowing down.When the TRC reinforcement layer was increased to 3,the failure mode of the corroded column had been changed,and the failure position was moved from the upper part of the column to the middle of the column.(3)On the basis of the calculation model of the normal section bearing capacity of small eccentric compression columns,and considering the influence of chloride drywet cycle and TRC’s constraint,the calculation model of the bearing capacity of small eccentric columns strengthened with TRC under chloride dry-wet was obtained.Camparing the theoretical values with the experimental values,there was a little deviation.