Article
Chemistry, Physical
Jacob Wittrup Schmidt, Christian Overgaard Christensen, Per Goltermann, Jose Sena-Cruz
Summary: A novel ductile near-surface mounted reinforcement (NSMR) CFRP strengthening system with high CFRP utilization is introduced in this paper, providing significant strengthening and ductility control. Experimental results show significant improvements in average deflection and yielding regimes compared to traditional strengthening methods, with reproducible and predictable strengthening effects.
Article
Construction & Building Technology
Jacob Wittrup Schmidt, John Dalsgaard Sorensen, Christian Overgaard Christensen
Summary: Introducing novel and complex structural solutions in the building industry can be challenging. This study presents a method to address these challenges and provides results from laboratory tests and a pilot project.
Article
Construction & Building Technology
Ceyhun Aksoylu
Summary: This study experimentally and analytically investigates the performance of shear deficient RC beams externally bonded with high strength CFRP and GFRP strips composite. The strengthened beams showed significant improvements in flexural ductility, energy dissipation, and inelastic performance. Based on the test results, GFRP, which is cheaper than CFRP, may be preferred for strengthening applications.
STEEL AND COMPOSITE STRUCTURES
(2022)
Article
Engineering, Civil
Haya H. Mhanna, Rami A. Hawileh, Jamal A. Abdalla, Ahmad S. D. Salama, Tarek Alkhrdaji
Summary: By anchoring high-modulus CFRP U-wrap shear reinforcement with properly designed CFRP anchors, this research program successfully delayed debonding of the U-wraps, significantly improved shear strength and ductility of beam specimens, and allowed for a higher strain in the CFRP laminates. The comparison between experimental and theoretical values also provided reasonable predictions on the shear capacity of anchored specimens.
JOURNAL OF COMPOSITES FOR CONSTRUCTION
(2021)
Article
Construction & Building Technology
Liying Guo, Mingke Deng, Ruizhe Li, Tong Li, Zhifang Dong
Summary: This study investigated the shear behaviors of RC short columns retrofitted with TR-FRC system and found that the strengthened columns had superior shear capacity, deformability, ductility and energy dissipation capacity compared to as-built counterparts. The stiffness degradation of the strengthened columns was further delayed with increased reinforcement ratio of CFRP grid. TR-FRC system remained effective in increasing the shear capacity of RC columns under smaller shear span-to-depth ratio.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Engineering, Civil
Leonardo Medeiros da Costa, Tiago Ancelmo de Carvalho Pires, Jose Jeferson Rego Silva
Summary: The aim of this study is to evaluate the efficiency of using the near-surface mounted (NSM) technique with carbon fiber-reinforced polymer (CFRP) laminates to strengthen fire-damaged reinforced concrete (RC) beams. Thirteen RC beams were heated for different durations according to the standard fire curve and then strengthened with NSM CFRP laminates at varying spacings. The NSM CFRP system effectively enhanced the shear strength of the beams, recovering or even increasing their initial capacity. Smaller spacing between laminates resulted in higher load capacities and stiffness, but a spacing of 75 mm led to failure due to peeling-out in the strengthening region.
ENGINEERING STRUCTURES
(2023)
Article
Mechanics
Mostafa E. Mobasher, Peter Taylor, Pawel B. Woelke, Norman A. Fleck, John W. Hutchinson, Allan Zhong
Summary: This study investigates the crucial problem of well casing connection in oil and gas exploration. Detailed simulations using the shear-extended GTN model show that the connection strength increases linearly with increasing indentation depth.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Construction & Building Technology
Nazar K. Oukaili, Hammad D. Merie
Summary: This paper investigates the influence of creating an opening near a column on the punching shear resistance of reinforced concrete bubbled slabs and the effectiveness of strengthening with CFRP sheets. The results show that openings decrease the load-carrying capacity of bubbled slabs, but CFRP strengthening can improve it.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2021)
Article
Polymer Science
Tae-Kyun Kim, Jong-Sup Park
Summary: The performance of concrete structures can degrade, but can be improved through strengthening methods such as FRPs and PS strands. Evaluation of ductility index using load-displacement results showed that most RC structures are in ductility or semi-ductility sections, while most PSC structures are brittle.
Article
Construction & Building Technology
Lokman Gemi, Mohammed Alsdudi, Ceyhun Aksoylu, Sakir Yazman, Yasin Onuralp Ozkilic, Musa Hakan Arslan
Summary: This study experimentally investigates the behavior of shear deficient reinforced concrete beams with rectangular cross-sections externally strengthened with CFRP composite under vertical load. The research finds that the direction and weight of CFRP composite are critical factors influencing the beam behavior, and should be considered in the calculation of shear capacity formulas.
STEEL AND COMPOSITE STRUCTURES
(2022)
Article
Engineering, Civil
R. W. Li, N. Zhang, H. Wu
Summary: The study investigates the effectiveness of carbon fiber reinforced polymer (CFRP) in enhancing the resistance of double-column RC bridge piers (DCBPs) to lateral consecutive impact. Experimental tests and numerical simulations were conducted, and a prototype bridge model was established for further simulations. The results demonstrate that CFRP strengthening can improve the impact resistance of piers and reduce deformation and damage to the entire bridge.
ENGINEERING STRUCTURES
(2022)
Article
Chemistry, Physical
Zheng-Nan Jing, Rong-Gui Liu, Gui-Hua Xie, Dan Liu
Summary: Experimental tests show that the performance features of deep T-beams do not meet the assumption of plane cross-section, and the 'strut-and-tie' model is applicable in such structures. Optimizing reinforcement systems can significantly improve the shear capacity of deep T-beams.
Article
Chemistry, Physical
Jian Wang, Tianqi Qiao, Aidong Wang, Xiudong Li, Tao Wang
Summary: A method of constructing high strength and toughness at the interface of Al/CFRP/Al laminate is proposed by adding resin and carbon nanotubes. Experimental results show that gullies and micropores on the surface of aluminum can increase the contact area between aluminum and matrix. Adding resin to the Al/CFRP interface improves the shear and bending strength as well as impact resistance. Mixing carbon nanotubes into the resin further enhances the mechanical properties. Carbon nanotubes between the CFRP layers strengthen and toughen the resin at the interface, increasing the bending strength and impact resistance by resisting resin damage and hindering crack propagation.
Review
Engineering, Civil
Amr Abdel Havez, Adil Al-Mayah
Summary: Carbon fiber-reinforced polymer (CFRP) materials are widely used for flexural strengthening of concrete structures. Non-prestressed CFRP materials increase the ultimate capacity but have little effect on serviceability. Prestressed CFRP laminates provide active repair and efficiently utilize the material's tensile strength. This paper reviews the use of prestressed CFRP laminates in conventionally and internally prestressed concrete structures, discussing the flexural behavior, failure modes, and serviceability performance of the strengthened members.
JOURNAL OF COMPOSITES FOR CONSTRUCTION
(2023)
Article
Construction & Building Technology
Yunxiao Lei, Shengwei Liu, Jianchang Zhao, Jiawei Zhang, Chenygu Bai
Summary: The mechanical properties of the bonding interface between CFRPs and wood were evaluated through testing and various models were proposed to investigate the interfacial bonding performance. Factors such as CFRP bond length and width were considered, and the results showed good agreement with the theoretical models. The research provides valuable information on the strengthening of wood structures using CFRPs.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Polymer Science
Yingwu Zhou, Yitao Weng, Limiao Li, Biao Hu, Xiaoxu Huang, Zhongfeng Zhu
Summary: This study investigated the influence of different volume replacement ratios of recycled FRP aggregate (RFA) on the compressive performance of recycled FRP aggregate concrete (RFAC). The results showed that as the RFA replacement ratio increased, the compressive strength and elastic modulus of RFAC gradually decreased, but its post-peak brittleness was significantly mitigated compared to natural coarse aggregate concrete (NAC).
Article
Construction & Building Technology
Xiaoxu Huang, Yiqi Bei, Lili Sui, Longyuan Li, Biao Hu, Yingwu Zhou
Summary: This study focused on the safety of maximum crack width in RC beams with high-strength steel bars, and proposed an optimized design procedure to control the crack width for reliability level. Compared with low-strength steel bars, high-strength ones require a relatively small steel ratio while maintaining equivalent bearing capacity and crack width safety level, demonstrating the economic advantages of high-strength steel bars through reasonable design.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Polymer Science
Yingwu Zhou, Guojian Wu, Limiao Li, Zhipei Guan, Menghuan Guo, Lei Yang, Zongjun Li
Summary: An innovative type of sustainable concrete containing LC3, seawater, sea sand, and surface-treated recycled aggregates is proposed in this study to replace traditional concrete, aiming to address resource shortage and carbon dioxide emissions. The bond behavior between sand-coated CFRP bars and the advanced sustainable concrete was investigated. The results showed that the slip increased with increased confinement, and the bond strength reached a critical ratio when LC3 was introduced. A multisegmented modified bond-slip model was developed to describe the four-stage bond behavior.
Article
Polymer Science
Guoqiang Gong, Menghuan Guo, Yingwu Zhou, Shuyue Zheng, Biao Hu, Zhongfeng Zhu, Zhenyu Huang
Summary: Limestone calcined clay cement (LC3) is successfully used to fabricate engineered cementitious composites (ECC) with high tensile strength and ductility. LC3 improves the bond strength between fibers and matrix, enhances fiber dispersion homogeneity, and contributes to strain hardening behavior. It also generates hydration products that densify the ECC matrix. Partial replacement of ordinary Portland cement (OPC) with LC3 reduces energy consumption and equivalent CO2 emissions.
Article
Mechanics
Zhongfeng Zhu, Yingwu Zhou, Zongjun Li, Haixiang Li, Biao Hu, Pengda Li
Summary: The utilization of fiber reinforced polymers (FRPs) is an effective solution against concrete deterioration. External FRP enhances the strength and durability of concrete and improves the internal concrete performance through confinement effect. A comprehensive database was established and reviewed, and the stress-strain relationship and confinement mechanisms were summarized to develop a versatile continuous model for FRP-confined concrete.
COMPOSITE STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Yingwu Zhou, Guoqiang Gong, Bin Xi, Menghuan Guo, Feng Xing, Cheng Chen
Summary: This study proposes the use of LC3 and FAC to produce sustainable lightweight ECC, investigating the effect of LC3 weight fraction on its properties and microstructure. Replacing OPC with LC3 slightly decreased compressive and tensile strength, but increased ductility. The high reactivity of LC3 decreased porosity and pore size.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Engineering, Civil
Yingwu Zhou, Xiaohan Wang, Biao Hu, Lili Sui, Fang Yuan
Summary: This study investigates the seismic retrofit of coastal bridge piers using FRP and ECC. Experimental results show that the retrofit significantly improves the seismic performance of the piers, especially for mildly corroded ones.
JOURNAL OF COMPOSITES FOR CONSTRUCTION
(2023)
Article
Construction & Building Technology
Fang Yuan, Yu-Fei Wu, Biao Hu
Summary: This study investigated the influence of compression reinforcement on the shear strength of RC beams through experimental testing and finite-element modeling. The research findings showed that the effect of compression reinforcement on shear strength is comparable to that of tensile reinforcement. A new model was developed to describe the additional shear strength contribution of compression reinforcement in RC members.
JOURNAL OF STRUCTURAL ENGINEERING
(2023)
Article
Construction & Building Technology
Yingwu Zhou, Ruyin Zhang, Ran Zhu, Zhipei Guan, Feng Xing, Menghuan Guo, Wanlin Cao, Biao Hu
Summary: A method of strengthening recycled coarse aggregate (RCA) by applying a fiber reinforced coating layer is proposed. The strengthening layer composition is explored, reducing the crushing index of the strengthened RCA (SRCA) by 37.4%. Microstructure investigations demonstrate densified interfacial transition zones (ITZs) in SRCA-made concrete (SRC), contributing to strength improvement. In SRC, distributed cracks are generated without major cracks, and the compressive strength is increased by 29.7% at 28 days. Numerical analyses show that cracks mainly develop in new mortar, while damage localization in both new and old ITZs is negligible until 80% post-peak.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Mechanics
Xiaoxu Huang, Yingwu Zhou, Weiwen Li, Biao Hu, Jiaxin Zhang
Summary: This paper investigates the reliability level of design guidelines for concrete structures shear strengthened with fiber reinforced polymer (FRP) and compares the accuracy and economy of different guidelines. The results show that the Chinese guideline is the most accurate for U-jacketing and fully wrapping, while both Chinese and American guidelines show satisfying predictions for side bonding. The reliability index for U-jacketing is generally larger than that for side bonding and smaller than fully wrapping. The Australian guideline provides the largest reliability indexes for U-jacketing and side bonding, while the British guideline provides the largest reliability indexes for fully wrapping. Besides the reliability level, the design economy also relies on the sensitivity of ss to design factors.
COMPOSITE STRUCTURES
(2023)
Article
Nanoscience & Nanotechnology
Yingwu Zhou, Li Zhuang, Zhiheng Hu, Biao Hu, Xiaoxu Huang, Shan Li, Menghuan Guo, Zhongfeng Zhu
Summary: This study solves the problem of using fiber-reinforced polymer (FRP) bars as reinforcement in concrete members by developing a compression yield (CY) structural system. The ductility of the concrete beam in this system comes from the compressive side, rather than the tensile side. Experimental and finite element modeling results are used to propose parametric equations and constitutive models to predict the mechanical behavior of the CY material.
REVIEWS ON ADVANCED MATERIALS SCIENCE
(2022)
Article
Nanoscience & Nanotechnology
Yingwu Zhou, Li Zhuang, Zhiheng Hu, Biao Hu, Xiaoxu Huang, Zhongfeng Zhu
Summary: This study aims to develop compression yielding (CY) materials by designing and optimizing perforations inside a mild steel block. The effects of key parameters on the stiffness, strength, and ductility of CY materials were experimentally investigated, and a finite element model was developed to predict their behavior.
REVIEWS ON ADVANCED MATERIALS SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Zhi Liang, Zhiheng Hu, Yingwu Zhou, Yufei Wu, Xiaoqing Zhou, Biao Hu, Menghuan Guo
Summary: This article introduces a new method to improve and reuse recycled aggregate concrete (RAC) by using compression casting and nano-silica treatment. The study finds that the combination of compression casting and nano-silica treatment can significantly enhance the compressive strength and reduce porosity of RAC.
NANOTECHNOLOGY REVIEWS
(2022)
