{"title":"腐蚀和火灾对热轧钢筋承载响应的综合影响","authors":"Faraz Tariq","doi":"10.1108/jsfe-09-2023-0034","DOIUrl":null,"url":null,"abstract":"PurposeAlthough separate studies on the influence of corrosion and fire exposure on the constitutive relationship of concrete and steel have been done, there is still a gap in knowledge on the influence of corrosion-temperature superimposition as nonlinear phenomenon. The current study is focused to investigate the response of hot-rolled steel bars subjected to corrosion-temperature superimposition.Design/methodology/approachUsing the accelerated corrosion-impressed-current technique, hot-rolled specimens with different levels of corrosion were obtained. The hot-rolled rebars were first corroded to target levels such as (6, 12, 18, 24, 30 and 36%) and subsequently subjected to target temperatures (250 °C, 400 °C, 550 °C, 800 °C and 950 °C), before tensile tests were carried out to evaluate the residual mechanical response.FindingsThe outcomes showed a significant decline in the parameters governing the mechanical properties of steel reinforcement due to the combined damage due to corrosion and fire. Corroded reinforcement still showed ductile failure after exposure to fire. Moreover, the combined loss of load-bearing characteristics due to corrosion and fire has little influence on the modulus of elasticity. The outcomes of this investigation provide a theoretical database for the assessment of aged structural elements exposed to combination after exposure to fire.Originality/valueThe information concerning structural material's response to corrosion-temperature combined damage is still limited. The cover of the reinforcement is designed to safeguard the reinforcing bars from foreign agencies but is often damaged and spalled off due to corrosion, rendering the reinforcing bars directly exposed. The study aims at the experimental production of fire conditions in a corrosion-damaged infrastructure to cover the aforementioned research gap. The effects of corrosion being superimposed by exposure to elevated temperatures on key parameters affecting mechanical behavior were examined.HighlightsInfluence of corrosion-temperature superimposition on the mechanical properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on the macro and microstructure properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on stress-strain curves of hot-rolled rebars.Influence of corrosion-temperature superimposition on tensile strength, modulus of elasticity and elongation of hot-rolled rebars.","PeriodicalId":45033,"journal":{"name":"Journal of Structural Fire Engineering","volume":null,"pages":null},"PeriodicalIF":0.9000,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Combined effects of corrosion and fire on load-carrying response of hot-rolled steel reinforcement\",\"authors\":\"Faraz Tariq\",\"doi\":\"10.1108/jsfe-09-2023-0034\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"PurposeAlthough separate studies on the influence of corrosion and fire exposure on the constitutive relationship of concrete and steel have been done, there is still a gap in knowledge on the influence of corrosion-temperature superimposition as nonlinear phenomenon. The current study is focused to investigate the response of hot-rolled steel bars subjected to corrosion-temperature superimposition.Design/methodology/approachUsing the accelerated corrosion-impressed-current technique, hot-rolled specimens with different levels of corrosion were obtained. The hot-rolled rebars were first corroded to target levels such as (6, 12, 18, 24, 30 and 36%) and subsequently subjected to target temperatures (250 °C, 400 °C, 550 °C, 800 °C and 950 °C), before tensile tests were carried out to evaluate the residual mechanical response.FindingsThe outcomes showed a significant decline in the parameters governing the mechanical properties of steel reinforcement due to the combined damage due to corrosion and fire. Corroded reinforcement still showed ductile failure after exposure to fire. Moreover, the combined loss of load-bearing characteristics due to corrosion and fire has little influence on the modulus of elasticity. The outcomes of this investigation provide a theoretical database for the assessment of aged structural elements exposed to combination after exposure to fire.Originality/valueThe information concerning structural material's response to corrosion-temperature combined damage is still limited. The cover of the reinforcement is designed to safeguard the reinforcing bars from foreign agencies but is often damaged and spalled off due to corrosion, rendering the reinforcing bars directly exposed. The study aims at the experimental production of fire conditions in a corrosion-damaged infrastructure to cover the aforementioned research gap. The effects of corrosion being superimposed by exposure to elevated temperatures on key parameters affecting mechanical behavior were examined.HighlightsInfluence of corrosion-temperature superimposition on the mechanical properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on the macro and microstructure properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on stress-strain curves of hot-rolled rebars.Influence of corrosion-temperature superimposition on tensile strength, modulus of elasticity and elongation of hot-rolled rebars.\",\"PeriodicalId\":45033,\"journal\":{\"name\":\"Journal of Structural Fire Engineering\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2024-07-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Structural Fire Engineering\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1108/jsfe-09-2023-0034\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"CONSTRUCTION & BUILDING TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Structural Fire Engineering","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1108/jsfe-09-2023-0034","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
摘要
目的虽然已经分别研究了腐蚀和火灾暴露对混凝土和钢材构成关系的影响,但对于腐蚀-温度叠加这一非线性现象的影响仍然缺乏了解。本研究主要探讨热轧钢筋在腐蚀-温度叠加作用下的响应。首先将热轧钢筋腐蚀至目标水平(6%、12%、18%、24%、30% 和 36%),然后将其置于目标温度(250 °C、400 °C、550 °C、800 °C 和 950 °C)下,再进行拉伸试验以评估残余机械响应。被腐蚀的钢筋在遭受火灾后仍会出现延展性破坏。此外,腐蚀和火灾共同造成的承重特性损失对弹性模量的影响很小。这项研究成果为评估暴露于火灾后的老化结构元件提供了一个理论数据库。钢筋保护层的设计是为了保护钢筋不受外来机构的破坏,但往往会因腐蚀而损坏和剥落,使钢筋直接暴露在外。本研究的目的是在腐蚀损坏的基础设施中进行火灾条件实验,以弥补上述研究空白。研究重点腐蚀-温度叠加对热轧钢筋机械性能的影响。腐蚀-温度叠加对热轧螺纹钢宏观和微观结构特性的影响腐蚀-温度叠加对热轧螺纹钢应力-应变曲线的影响腐蚀-温度叠加对热轧螺纹钢抗拉强度、弹性模量和延伸率的影响
Combined effects of corrosion and fire on load-carrying response of hot-rolled steel reinforcement
PurposeAlthough separate studies on the influence of corrosion and fire exposure on the constitutive relationship of concrete and steel have been done, there is still a gap in knowledge on the influence of corrosion-temperature superimposition as nonlinear phenomenon. The current study is focused to investigate the response of hot-rolled steel bars subjected to corrosion-temperature superimposition.Design/methodology/approachUsing the accelerated corrosion-impressed-current technique, hot-rolled specimens with different levels of corrosion were obtained. The hot-rolled rebars were first corroded to target levels such as (6, 12, 18, 24, 30 and 36%) and subsequently subjected to target temperatures (250 °C, 400 °C, 550 °C, 800 °C and 950 °C), before tensile tests were carried out to evaluate the residual mechanical response.FindingsThe outcomes showed a significant decline in the parameters governing the mechanical properties of steel reinforcement due to the combined damage due to corrosion and fire. Corroded reinforcement still showed ductile failure after exposure to fire. Moreover, the combined loss of load-bearing characteristics due to corrosion and fire has little influence on the modulus of elasticity. The outcomes of this investigation provide a theoretical database for the assessment of aged structural elements exposed to combination after exposure to fire.Originality/valueThe information concerning structural material's response to corrosion-temperature combined damage is still limited. The cover of the reinforcement is designed to safeguard the reinforcing bars from foreign agencies but is often damaged and spalled off due to corrosion, rendering the reinforcing bars directly exposed. The study aims at the experimental production of fire conditions in a corrosion-damaged infrastructure to cover the aforementioned research gap. The effects of corrosion being superimposed by exposure to elevated temperatures on key parameters affecting mechanical behavior were examined.HighlightsInfluence of corrosion-temperature superimposition on the mechanical properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on the macro and microstructure properties of hot-rolled rebars.Influence of corrosion-temperature superimposition on stress-strain curves of hot-rolled rebars.Influence of corrosion-temperature superimposition on tensile strength, modulus of elasticity and elongation of hot-rolled rebars.