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Behavior of FRP-confined FRP spiral reinforced concrete square columns (FCFRCs) under axial compression SCIE
期刊论文 | 2022 , 45 | JOURNAL OF BUILDING ENGINEERING
WoS核心集被引次数: 38
摘要&关键词 引用

摘要 :

Fiber-reinforced polymer (FRP) confinement has been demonstrated to be efficient in enhancing the deformation and strength capacities of concrete, while Polyethylene terephthalate (PET) FRP-confined concrete easily exhibits a strain-softening stress-strain behavior, especially for PET FRP-confined concrete in square columns. In this study, novel PET FRP-confined FRP spiral reinforced concrete square columns (FCFRSCs) are proposed. Capitalizing the benefits of internal FRP spiral reinforcement, the strain-softening behavior of PET FRP-confined concrete is expected to be alleviated, leading to excellent mechanical performance of the proposed square columns. The axial compressive behavior of FCFRSCs, as well as square concrete-filled PET FRP tube columns (CFFTs) and FRP reinforced concrete columns (FRCs) as reference columns, were investigated via experimentation. The experimental results show that the strain softening behavior of confined concrete in FCFRSCs has been substantially enhanced with the internal FRP reinforcement, confirming the viability of the system. The strain softening behavior of FRP-confined concrete after the first peak is prevented and a hardening behavior is achieved for concrete in FCFRSCs, especially when the GFRP spiral pitch is 30 mm.

关键词 :

Axial load-strain behavior Axial load-strain behavior Confinement Confinement Fiber-reinforced polymer (FRP) bars Fiber-reinforced polymer (FRP) bars FRP spiral FRP spiral Glass FRP (GFRP) Glass FRP (GFRP) Reinforced concrete columns Reinforced concrete columns

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GB/T 7714 Zhou, Jie-Kai , Lin, Wen-Kai , Guo, Shao-Xiong et al. Behavior of FRP-confined FRP spiral reinforced concrete square columns (FCFRCs) under axial compression [J]. | JOURNAL OF BUILDING ENGINEERING , 2022 , 45 .
MLA Zhou, Jie-Kai et al. "Behavior of FRP-confined FRP spiral reinforced concrete square columns (FCFRCs) under axial compression" . | JOURNAL OF BUILDING ENGINEERING 45 (2022) .
APA Zhou, Jie-Kai , Lin, Wen-Kai , Guo, Shao-Xiong , Zeng, Jun-Jie , Bai, Yu-Lei . Behavior of FRP-confined FRP spiral reinforced concrete square columns (FCFRCs) under axial compression . | JOURNAL OF BUILDING ENGINEERING , 2022 , 45 .
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一种外包FRP对纵筋侧向支撑刚度的计算方法 incoPat
专利 | 2021-01-08 | CN202110024647.8
摘要&关键词 引用

摘要 :

本发明公开了一种外包FRP对纵筋侧向支撑刚度的计算方法,根据柱截面纵筋的数量和截面的对称性进行等截面划分,确定曲线梁模型;采用分析导向应力应变模型,获得轴向应变、轴向应力、侧向应变和侧向应力及其增量形式;确定FRP约束混凝土在轴向的剪切模量以及FRP约束混凝土保护层在环向的弹性模量;将该组合截面梁等效为单一材料截面,并求出其截面特性;利用结构力学求解超静定结构的方法,求解在任一给定的荷载作用下,在该作用点发生的位移;求出等效刚度。本发明具有高准确性、可更新可修改等优点,且运用了成熟的结构力学求解超静定结构的计算方法,计算简单,准确性高,具有很强的研究应用价值。

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GB/T 7714 白玉磊 , 孙鹏轩 , 贾俊峰 et al. 一种外包FRP对纵筋侧向支撑刚度的计算方法 : CN202110024647.8[P]. | 2021-01-08 .
MLA 白玉磊 et al. "一种外包FRP对纵筋侧向支撑刚度的计算方法" : CN202110024647.8. | 2021-01-08 .
APA 白玉磊 , 孙鹏轩 , 贾俊峰 , 张玉峰 , 杨洪龙 . 一种外包FRP对纵筋侧向支撑刚度的计算方法 : CN202110024647.8. | 2021-01-08 .
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预应力连接预制节段桥墩拟静力试验数值仿真分析
会议论文 | 2021 | 第30届全国结构工程学术会议
摘要&关键词 引用

摘要 :

预应力连接预制节段桥墩已较为广泛地应用于美国低震区桥梁,但在我国的工程应用甚少。由于预制节段桥墩的震害资料缺乏,且其抗震机理不明确、设计方法不完善,在高震区应用较少。本文基于预应力连接预制节段桥墩缩尺模型的拟静力试验测试,采用有限元分析软件ABAQUS建立其精细化数值模型,进行了单、斜向往复荷载作用下墩柱拟静力试验数值仿真,将桥墩的损伤情况、滞回行为与试验结果进行了对比分析。结果表明,数值模型输入的相关参数和设置的相互作用关系可较好地再现试验结果,试验和模拟结果均表明斜向加载的构件较单向加载的构件损伤更为严重,构件更早屈服,残余位移较大,墩柱构件最大偏移率为4%时其残余偏移率已超过1%。常规设...

关键词 :

单、斜向往复荷载 单、斜向往复荷载 抗震性能 抗震性能 有限元分析模型 有限元分析模型 节段拼装桥墩 节段拼装桥墩 预应力筋 预应力筋

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GB/T 7714 张凯迪 , 贾俊峰 , 白玉磊 et al. 预应力连接预制节段桥墩拟静力试验数值仿真分析 [C] //第30届全国结构工程学术会议论文集(Ⅱ册) . 2021 .
MLA 张凯迪 et al. "预应力连接预制节段桥墩拟静力试验数值仿真分析" 第30届全国结构工程学术会议论文集(Ⅱ册) . (2021) .
APA 张凯迪 , 贾俊峰 , 白玉磊 , 郭扬 . 预应力连接预制节段桥墩拟静力试验数值仿真分析 第30届全国结构工程学术会议论文集(Ⅱ册) . (2021) .
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Experimental evaluation of seismic performance of corroded precast RC bridge columns and the retrofit measure using CFRP jackets SCIE
期刊论文 | 2021 , 245 | ENGINEERING STRUCTURES
WoS核心集被引次数: 8
摘要&关键词 引用

摘要 :

Precast reinforced concrete (RC) bridge columns are critical substructure components for Accelerated Bridge Construction (ABC), which attracts significant attention all over the world in recent decades. However, seismic behavior of precast RC bridge columns in corrosive environment and related retrofit methods are rarely studied. To fill out this knowledge gap, in this study, four, 1/4-scaled precast RC bridge columns of various corrosion levels were designed, constructed and tested in a pseudo-static manner to gain in-depth understanding of corrosion on the seismic behavior of this type of columns. Two of these columns with higher corrosion levels were retrofitted with carbon fiber reinforced polymer (CFRP) fabrics in the plastic hinge zone to assess the effectiveness of this retrofit measure. Corrosion levels of the specimens were obtained through an electrochemical method to accelerate the corrosion process at the plastic region. It was found that corrosion in the reinforcement was uneven across the section and was much severer at the joint of precast bridge columns. It was also found that even the low corrosion level of longitudinal reinforcement (i.e. 7.2%) can result in a significant decrease (i.e. >15%) in the lateral load capacity, energy dissipation, ductility and ultimate displacement. Hence, the retrofit of corroded precast RC bridge columns should be performed at low-level of corrosion. The test results also indicate that corrosion has more adverse effect on the ultimate displacement and ductility than the strength. In addition, retrofitting bridge columns of higher corrosion levels (i.e., >10%) using CFRP jackets could effectively protect the columns from damage in the plastic hinge zones. However, the damage pattern was shifted to fracture of the longitudinal rebars at the column-footing interface, resulting in substantial reduction in the ultimate displacement capacity. Therefore, it is not recommended to retrofit precast RC bridge columns of high corrosion level using CFRP jackets alone.

关键词 :

CFRP CFRP Corrosion Corrosion Precast RC bridge columns Precast RC bridge columns Quasi-static test Quasi-static test Seismic performance Seismic performance

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GB/T 7714 Wang, Xu , Wu, Suiwen , Jia, Junfeng et al. Experimental evaluation of seismic performance of corroded precast RC bridge columns and the retrofit measure using CFRP jackets [J]. | ENGINEERING STRUCTURES , 2021 , 245 .
MLA Wang, Xu et al. "Experimental evaluation of seismic performance of corroded precast RC bridge columns and the retrofit measure using CFRP jackets" . | ENGINEERING STRUCTURES 245 (2021) .
APA Wang, Xu , Wu, Suiwen , Jia, Junfeng , Li, Huaqiang , Wei, Yanjian , Zhang, Kaidi et al. Experimental evaluation of seismic performance of corroded precast RC bridge columns and the retrofit measure using CFRP jackets . | ENGINEERING STRUCTURES , 2021 , 245 .
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Rate-dependent compressive behavior of concrete confined with Large-Rupture-Strain (LRS) FRP SCIE
期刊论文 | 2021 , 272 | COMPOSITE STRUCTURES
WoS核心集被引次数: 19
摘要&关键词 引用

摘要 :

The polyethylene naphthalene (PEN) and polyethylene terephthalate (PET) fibers have a tensile rupture strain of over 5%, and hence they are referred to as large-rupture-strain (LRS) fiber reinforced polymer (FRP) materials. Their large rupture strain characteristics may contribute to significant improvement of the impact resistance of reinforced concrete (RC) structures. This study investigates the strain rate effect on LRS FRP-confined concrete through Split Hopkinson Pressure Bar (SHPB) test. Results revealed that LRS FRP-confined concrete specimens exhibited superior impact resistance behaviors compared to the counterpart confined with CFRP composites when subjected to a single impact. The critical strain, compressive strength and toughness of the LRS FRP-confined concrete specimen increased with increasing strain rate. Due to the large rupture strain characteristics, the LRS FRP-confined concrete specimen virtually had no visible damage after a single impact. To study the damage evolution mechanism of concrete, the specimens were impacted for multiple times with the same energy until the failure of the specimen. Due to progressive concrete damage, the dynamic compressive strength and toughness experienced a decrease during multiple impacts. These findings might promote the application of LRS FRP materials in the field of impact resistance design of RC structures as a promising external jacketing material.

关键词 :

LRS FRP-confined concrete LRS FRP-confined concrete Repeated impact Repeated impact SHPB SHPB Strain rate effect Strain rate effect

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GB/T 7714 Yan, Zhi-Wei , Bai, Yu-Lei , Ozbakkaloglu, Togay et al. Rate-dependent compressive behavior of concrete confined with Large-Rupture-Strain (LRS) FRP [J]. | COMPOSITE STRUCTURES , 2021 , 272 .
MLA Yan, Zhi-Wei et al. "Rate-dependent compressive behavior of concrete confined with Large-Rupture-Strain (LRS) FRP" . | COMPOSITE STRUCTURES 272 (2021) .
APA Yan, Zhi-Wei , Bai, Yu-Lei , Ozbakkaloglu, Togay , Gao, Wan-Yang , Zeng, Jun-Jie . Rate-dependent compressive behavior of concrete confined with Large-Rupture-Strain (LRS) FRP . | COMPOSITE STRUCTURES , 2021 , 272 .
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Cyclic stress-strain model for large-rupture strain fiber-reinforced polymer (LRS FRP)-confined concrete EI
期刊论文 | 2021 , 42 | Journal of Building Engineering
摘要&关键词 引用

摘要 :

Large-rupture strain (usually larger than 5%) fiber-reinforced polymer (LRS FRP) composites are attractive materials for the seismic retrofit of concrete structures. Jacketing LRS FRP on concrete columns can effectively improve the ultimate strength and deformation of a concrete structure and make the concrete structure have excellent ductility and superior energy absorption capacity. In comparison with conventional FRP, the concrete under LRS FRP confinement experiences a more severe damage process when it is under large deformation. The confining pressure at the large deformation can alter the concrete plastic flow and significantly affect the cyclic stress-strain path of LRS-FRP confined concrete. This study evaluates the performance of existing cyclic models (e.g., unloading path, reloading path, and plastic strain) using a database including both traditional and LRS FRP-confined concrete. Through an analytical study on the cyclic response of LRS FRP-confined concrete, two key parameters (plastic strain and stress degradation) were found to significantly influence the cyclic behavior of LRS FRP-confined concrete. By defining these two critical parameters, a new cyclic stress-strain model was developed for LRS FRP confined-concrete with good performance. The proposed cyclic model was also applicable in predicting both post-peak strain hardening and softening behavior when used in a stiffness-based envelope model. © 2021 Elsevier Ltd

关键词 :

Concrete buildings Concrete buildings Concrete construction Concrete construction Fiber reinforced plastics Fiber reinforced plastics Plastic deformation Plastic deformation Reinforced concrete Reinforced concrete Reinforcement Reinforcement Stiffness Stiffness Strain hardening Strain hardening Stress-strain curves Stress-strain curves Unloading Unloading

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GB/T 7714 Bai, Yu-Lei , Mei, Shi-Jie , Li, Pengda et al. Cyclic stress-strain model for large-rupture strain fiber-reinforced polymer (LRS FRP)-confined concrete [J]. | Journal of Building Engineering , 2021 , 42 .
MLA Bai, Yu-Lei et al. "Cyclic stress-strain model for large-rupture strain fiber-reinforced polymer (LRS FRP)-confined concrete" . | Journal of Building Engineering 42 (2021) .
APA Bai, Yu-Lei , Mei, Shi-Jie , Li, Pengda , Xu, Junjie . Cyclic stress-strain model for large-rupture strain fiber-reinforced polymer (LRS FRP)-confined concrete . | Journal of Building Engineering , 2021 , 42 .
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Compressive behavior and modelling of engineered cementitious composite (ECC) confined with LRS FRP and conventional FRP SCIE
期刊论文 | 2021 , 272 | COMPOSITE STRUCTURES
WoS核心集被引次数: 28
摘要&关键词 引用

摘要 :

A combination of core engineered cementitious composite (ECC) and external fiber-reinforced polymer (FRP) composites can solve the problems of insufficient ductility and durability of normal concrete (NC) in adverse environments and improve bearing capacity. However, existing studies on the performance of ECC strengthened by FRP are very limited-particularly the research on large rupture strain (LRS) FRP-confined ECC. In this study, an experimental investigation of LRS FRP and conventional glass FRP-confined ECC cylinders with different confinement levels under axial compression is presented. It is found that the application of external FRP jackets leads to a significant improvement in the compressive strength and deformation of the core ECC. LRS FRP-confined ECC exhibits a higher ultimate deformation than conventional FRP-confined ECC. The dilation behavior, axial stress-strain behavior, and energy dissipation capacity between FRP-confined ECC and FRPconfined NC under the same confinement level are compared, and the former exhibits a significantly larger ductility and energy dissipation capacity than the latter. The results also indicate that most existing models are unable to accurately predict the compressive behavior of FRP-confined ECC. To address this, a dilation model and an axial stress-strain model of FRP-confined NC are modified to extend their application to FRPconfined ECC.

关键词 :

Compressive behavior Compressive behavior Confinement Confinement Engineered cementitious composite (ECC) Engineered cementitious composite (ECC) Fiber-reinforced polymer (FRP) Fiber-reinforced polymer (FRP) Large rupture strain (LRS) Large rupture strain (LRS)

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GB/T 7714 Yuan, Wan-Ying , Han, Qiang , Bai, Yu-Lei et al. Compressive behavior and modelling of engineered cementitious composite (ECC) confined with LRS FRP and conventional FRP [J]. | COMPOSITE STRUCTURES , 2021 , 272 .
MLA Yuan, Wan-Ying et al. "Compressive behavior and modelling of engineered cementitious composite (ECC) confined with LRS FRP and conventional FRP" . | COMPOSITE STRUCTURES 272 (2021) .
APA Yuan, Wan-Ying , Han, Qiang , Bai, Yu-Lei , Du, Xiu-Li , Yan, Zhi-Wei . Compressive behavior and modelling of engineered cementitious composite (ECC) confined with LRS FRP and conventional FRP . | COMPOSITE STRUCTURES , 2021 , 272 .
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Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders SCIE
期刊论文 | 2021 , 276 | COMPOSITE STRUCTURES
WoS核心集被引次数: 20
摘要&关键词 引用

摘要 :

This paper presents an experimental study on the impact performance of concrete columns confined with largerupture-strain (LRS, tensile rupture strain >= 5%) fiber reinforced polymer (FRP) jackets. A total of 32 concrete specimens were prepared and tested using large-capacity drop-weight equipment. The test variables included four impact heights (2, 3, 4 and 5 m), three types of FRP, i.e., aramid FRP (AFRP), polyethylene naphthalate (PEN) FRP and polyethylene terephthalate (PET) FRP and two layers of FRP jackets (1 and 2). The time histories of impact force and FRP rupture strain as well as failure modes were obtained from the test. Compared to the AFRP-confined concrete specimen with similar jacket stiffness, the core concrete of the LRS FRP-confined specimen was less damaged due to the large-rupture-strain characteristic. The impact force increased and the impact duration decreased with increasing impact height. The impact duration of concrete specimens confined with LRS FRP was longer than that of the AFRP-confined concrete column. Results showed that the impactresistance behaviours of LRS FRP-confined concrete column outperformed its companion column confined with AFRP. Besides, increasing the thickness of FRP jacket can enhance the impact resistance capacity. These findings may facilitate the impact resistance strengthening/retrofitting of RC structures with the application of LRS FRP composites.

关键词 :

Drop-weight Drop-weight Failure mode Failure mode Impact resistance Impact resistance LRS FRP-confined concrete LRS FRP-confined concrete

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GB/T 7714 Yan, Zhi-Wei , Bai, Yu-Lei , Ozbakkaloglu, Togay et al. Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders [J]. | COMPOSITE STRUCTURES , 2021 , 276 .
MLA Yan, Zhi-Wei et al. "Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders" . | COMPOSITE STRUCTURES 276 (2021) .
APA Yan, Zhi-Wei , Bai, Yu-Lei , Ozbakkaloglu, Togay , Gao, Wan-Yang , Zeng, Jun-Jie . Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders . | COMPOSITE STRUCTURES , 2021 , 276 .
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Mechanical behavior of large-rupture-strain (LRS) polyethylene naphthalene fiber bundles at different strain rates and temperatures SCIE
期刊论文 | 2021 , 297 | CONSTRUCTION AND BUILDING MATERIALS
WoS核心集被引次数: 23
摘要&关键词 引用

摘要 :

This paper presents the results of an experimental study aimed at investigating the effects of strain rate and temperature on the tensile mechanical properties of polyethylene naphthalene (PEN) fiber bundles by using a drop-weight impact system. A total of 65 specimens with a gauge length of 25 mm were prepared and tested. The test variables included five different strain rates (1/600, 40, 80, 120 and 160 s(1)) and five different temperatures (-50, -25, 0, 25 and 50 degrees C). The results indicated that the tensile strengths and elastic moduli of the specimens increased with the strain rate, whereas the failure strain decreased and the toughness remained almost unchanged with the increase of the strain rate. The tensile strength, toughness and failure strain initially improved and then reduced with an increasing temperature from - 50 degrees C to 50 degrees C. A Weibull distribution model was implemented to describe the degree of variability in the tensile strength of PEN fiber bundles for future use. (C) 2021 Elsevier Ltd. All rights reserved.

关键词 :

Polyethylene naphthalene (PEN) fiber Polyethylene naphthalene (PEN) fiber Strain rate Strain rate Temperature effect Temperature effect Tensile mechanical properties Tensile mechanical properties Weibull analysis Weibull analysis

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GB/T 7714 Bai, Yu-Lei , Yan, Zhi-Wei , Ozbakkaloglu, Togay et al. Mechanical behavior of large-rupture-strain (LRS) polyethylene naphthalene fiber bundles at different strain rates and temperatures [J]. | CONSTRUCTION AND BUILDING MATERIALS , 2021 , 297 .
MLA Bai, Yu-Lei et al. "Mechanical behavior of large-rupture-strain (LRS) polyethylene naphthalene fiber bundles at different strain rates and temperatures" . | CONSTRUCTION AND BUILDING MATERIALS 297 (2021) .
APA Bai, Yu-Lei , Yan, Zhi-Wei , Ozbakkaloglu, Togay , Gao, Wan-Yang , Zeng, Jun-Jie . Mechanical behavior of large-rupture-strain (LRS) polyethylene naphthalene fiber bundles at different strain rates and temperatures . | CONSTRUCTION AND BUILDING MATERIALS , 2021 , 297 .
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自复位U形钢板耗能支撑设计与滞回性能分析
期刊论文 | 2021 , 51 (5) , 754-761 | 东南大学学报(自然科学版)
摘要&关键词 引用

摘要 :

为控制地震作用下结构的残余变形,提出了一种自复位U形钢板耗能支撑,采用组合碟簧作为复位系统提供复位能力,将U形钢板作为耗能系统提供耗能能力.在耗能系统和复位系统的双线性弹性模型基础上,建立了支撑恢复力模型,并对支撑进行数值模拟,分析不同设计参数对支撑滞回性能的影响.结果 表明,自复位U形钢板耗能支撑具有稳定的耗能能力和良好的自复位能力,且耗能能力随U形钢板宽度的增加而增强,复位能力随组合碟簧初始预压力的增大而增强,建议将组合碟簧的预压力取值为大于耗能系统的屈服强度且小于耗能系统的极限强度.

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GB/T 7714 贾俊峰 , 赵凌云 , 白玉磊 et al. 自复位U形钢板耗能支撑设计与滞回性能分析 [J]. | 东南大学学报(自然科学版) , 2021 , 51 (5) : 754-761 .
MLA 贾俊峰 et al. "自复位U形钢板耗能支撑设计与滞回性能分析" . | 东南大学学报(自然科学版) 51 . 5 (2021) : 754-761 .
APA 贾俊峰 , 赵凌云 , 白玉磊 , 周述美 , 刘钊 , 李茂昌 . 自复位U形钢板耗能支撑设计与滞回性能分析 . | 东南大学学报(自然科学版) , 2021 , 51 (5) , 754-761 .
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