scholarly journals Degradation of the In-plane Shear Modulus of Structural BFRP Laminates Due to High Temperature

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3361 ◽  
Author(s):  
Yu-Jia Hu ◽  
Cheng Jiang ◽  
Wei Liu ◽  
Qian-Qian Yu ◽  
Yun-Lai Zhou
Keyword(s):  
High Temperature ◽  
Shear Modulus ◽  
Image Correlation ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Fiber Direction ◽  
Fiber Reinforced ◽  
Plane Shear ◽  
Analytical Derivation ◽  
Reinforced Polymer

The behavior of fiber reinforced polymer (FRP) composites at high temperature is a critical issue that needs to be clearly understood for their structural uses in civil engineering. However, due to technical difficulties during testing at high temperature, limited experimental investigations have been conducted regarding the thermal behavior of basalt fiber reinforced polymer (BFRP) composites, especially for the in-plane shear modulus of BFRP laminates. To this end, both an analytical derivation and an experimental program were carried out in this work to study the in-plane shear modulus of BFRP laminates. After the analytical derivation, the in-plane shear modulus was investigated as a function of the elastic modulus in different directions (0°, 45° and 90° of the load-to-fiber angle) and Poisson's ratio in the fiber direction. To obtain the in-plane shear modulus, the four parameters were tested at different temperatures from 20 to 250 °C. A novel non-contacting digital image correlation (DIC) sensing system was adopted in the high-temperature tests to measure the local strain field on the FRP samples. Based on the test results, it was found that the elastic moduli in different directions were reduced to a very low level (less than 20%) from 20 to 250 °C. Furthermore, the in-plane shear modulus of BFRP at 250 °C was only 3% of that at 20 °C.

Shear Failure Analysis of Concrete Beams Reinforced with Newly Developed GFRP Stirrups

2006 ◽  
Vol 324-325 ◽  
pp. 995-998
Author(s):  
Cheol Woo Park ◽  
Jong Sung Sim
Keyword(s):  
Failure Modes ◽  
Shear Failure ◽  
Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Shear Stresses ◽  
Fiber Reinforced ◽  
Shear Span ◽  
Reinforced Polymer ◽  
A New Technique

Even though the application of fiber reinforced polymer (FRP) as a concrete reinforcement becomes more common with various advantages, one of the inherent shortcomings may include its brittleness and on-site fabrication and handling. Therefore, the shape of FRP products has been limited only to a straight bar or sheet type. This study suggests a new technique to use glass fiber reinforced polymer (GFRP) bars for the shear reinforcement in concrete beams, and investigates its applicability. The developed GFRP stirrup was used in the concrete instead of ordinary steel stirrups. The experimental program herein evaluates the effectiveness of the GFRP stirrups with respect to different shear reinforcing ratios under three different shear span-to-depth testing schemes. At the same shear reinforcing ratio, the ultimate loads of the beams were similar regardless the shear reinforcing materials. Once a major crack occurs in concrete, however, the failure modes seemed to be relatively brittle with GFRP stirrups. From the measured strains on the surface of concrete, the shear stresses sustained by the stirrups were calculated and the efficiency of the GFRP stirrups was shown to be 91% to 106% depending on the shear span-to-depth ratio.

scholarly journals Seismic Retrofitting of Traditional Masonry with Pultruded FRP Profiles

2020 ◽  
Vol 10 (7) ◽  
pp. 2489 ◽  
Author(s):  
Francesca Sciarretta
Keyword(s):  
Maximum Load ◽  
Seismic Retrofitting ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Future Research ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Before And After ◽  
Basic Frame

This paper presents a study on the potentiality of seismic retrofitting solutions with pultruded Fiber Reinforced Polymer (FRP) profiles. This material can be used in connected frames providing lightweight, corrosion-free and reversible retrofitting of masonry buildings with the moderate requirements of surface preservation. In a hypothetical case study, an experimental program was designed; monotonic shear tests on a half-size physical model of the sample wall were performed to assess the structural performance before and after retrofitting with a basic frame of pultruded Glass Fiber Reinforced Polymer (GFRP) C-shaped profiles, connected to the masonry by steel threaded bar connections. During the tests, the drift, the diagonal displacements in the masonry and the micro-strain in the profiles were measured. The retrofitted system has proven very effective in delaying crack appearance, increasing the maximum load (+85% to +93%) and ultimate displacement (up to +303%). The failure mode switches from rocking to a combination of diagonal cracking and bed joint sliding. The gauge recordings show a very limited mechanical exploitation of the GFRP material, despite the noticeable effectiveness of the retrofit. The application seems thus promising and worth a deeper research focus. Finally, a finite element modelling approach has been developed and validated, and it will be useful to envisage the effects of the proposed solution in future research.

Experimental evaluation of the tensile bonding strength of the basalt fiber-reinforced polymer–concrete interface

2020 ◽  
Vol 23 (15) ◽  
pp. 3323-3334
Author(s):  
Buntheng Chhorn ◽  
WooYoung Jung
Keyword(s):  
High Temperature ◽  
Bonding Strength ◽  
Basalt Fiber ◽  
Fiber Reinforced Polymer ◽  
Polymer Concrete ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Interface Bonding Strength ◽  
Concrete Interface ◽  
Basalt Fiber Reinforced Polymer

The bonding performance of basalt fiber-reinforced polymer and concrete substrate has a significant effect on the reliability of externally strengthened existing concrete structure, due to being the most vulnerable element to failure in this fiber-reinforced polymer–concrete strengthening system. Its failure can result in the failure of the whole structure. Although many previous researchers have been interested in the tensile bonding strength of carbon fiber-reinforced polymer and glass fiber-reinforced polymer–concrete interface, that of basalt fiber-reinforced polymer–concrete interface has been very limited. Thus, the objective of this study is to experimentally assess the tensile bonding strength of the basalt fiber-reinforced polymer–concrete interface. The effects of high temperature, freezing–thawing cycles, type of resin, and concrete crack widths on the tensile bonding strength are also investigated. The pull-off experiment is conducted according to ASTM D7522/D7522M-15. A total of 205 core specimens of 50 mm diameter and 10 mm depth were taken from 41 concrete beams. The experimental results illustrate that both freezing–thawing and high-temperature condition have a substantial effect on the bonding strength of the basalt fiber-reinforced polymer–concrete interface. Bonding strength was decreased within the range of about 9%–30% when the number of freezing–thawing cycles increases from 100 to 300; likewise, it was decreased up to 30% when the exposure temperature rises to 200°C. Also, the specimens which were repaired to close their cracks by epoxy resin had no significant effect on the bonding strength of basalt fiber-reinforced polymer–concrete interface, when the specimens had crack width of less than 1.5 mm.

Seismic behavior of concrete bridge columns confined with fiber-reinforced polymer stay-in-place formwork

2017 ◽  
Vol 21 (4) ◽  
pp. 613-623 ◽  
Author(s):  
Gamal Elnabelsy ◽  
Murat Saatcioglu
Keyword(s):  
Carbon Fiber ◽  
Bridge Columns ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced Polymers ◽  
Carbon Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Carbon Fiber Reinforced ◽  
Polymer Tubes

One of the applications of fiber-reinforced polymers in bridge construction is stay-in-place formwork. Fiber-reinforced polymer stay-in-place formwork, in the form of preformed tubes, provides easy form assembly, protection of steel reinforcement and concrete against corrosion and chemical attacks while also improving the strength and ductility of structural elements in earthquake resistant construction. Experimental research was conducted to investigate the seismic performance of fiber-reinforced polymer stay-in-place formwork for bridge columns. Tests of large-scale specimens were conducted under simulated seismic loading. The experimental program included circular and square columns confined with carbon fiber–reinforced polymer tubes. The results indicate that the use of carbon fiber–reinforced polymer tubes increases column inelastic deformability significantly. Bridge columns under low levels of axial compression exhibit inelastic drift capacities in excess of 4% before failing in flexural tension due to the rupturing of longitudinal reinforcement. These observations and experimental results were used to develop a displacement-based design procedure for concrete confinement for fiber-reinforced polymer–encased concrete columns. This article presents an overview of the experimental program and the design approach developed.

scholarly journals Repair and Strengthening of Bridges in Indiana Using Fiber Reinforced Polymer Systems: Volume 2–FRP Flexural Strengthening and End Region Repair Experimental Programs

2021 ◽  
Author(s):  
William B. Rich ◽  
Robert R. Jacobs ◽  
Christopher S. Williams ◽  
Robert J. Frosch
Keyword(s):  
Effective Means ◽  
The State ◽  
Concrete Bridges ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Concrete Bridge ◽  
Fiber Reinforced ◽  
Near Surface ◽  
Flexural Strengthening ◽  
Reinforced Polymer

For bridges that are experiencing deterioration, action is needed to ensure the structural performance is adequate for the demands imposed. Innovate repair and strengthening techniques can provide a cost-effective means to efficiently and safely extend the service lives of bridges. The use of fiber reinforced polymer (FRP) systems for the repair and strengthening of concrete bridges is increasing in popularity. Recognizing the potential benefits of the widespread use of FRP, a research project was initiated to determine the most appropriate applications of FRP in Indiana and provide recommendations for the use of FRP in the state for the repair and strengthening of bridges. The details of the research are presented in two volumes. Volume 1 provides the details of a study conducted to (i) summarize the state-of-the-art for the application of FRP to concrete bridges, (ii) identify successful examples of FRP implementation for concrete bridges in the literature and examine past applications of FRP in Indiana through case studies, and (iii) better understand FRP usage and installation procedures in the Midwest and Indiana through industry surveys. Volume 2 presents two experimental programs that were conducted to develop and evaluate various repair and strengthening methodologies used to restore the performance of deteriorated concrete bridge beams. The first program investigated FRP flexural strengthening methods, with focus placed on adjacent box beam bridges. The second experimental program examined potential techniques for repairing deteriorated end regions of prestressed concrete bridge girders. Externally bonded FRP and near-surface-mounted (NSM) FRP were considered in both programs.

scholarly journals Manufacturing of Banana Fiber Composites for different Compositions and its Experimental Tensile Testing

2021 ◽  
Author(s):  
Popat B Asabe ◽  
Shrikrushn B Bhosale ◽  
Sonali S Patil ◽  
Avinash K Parkhe
Keyword(s):  
Composite Materials ◽  
Polymer Composites ◽  
Resin Composite ◽  
Engineering Application ◽  
Fiber Composites ◽  
Fiber Reinforced Polymer ◽  
Fiber Direction ◽  
Fiber Reinforced ◽  
Banana Fiber ◽  
Reinforced Polymer

The world's attention is now focused on resources that are environmentally friendly and recyclable. Due to growing environmental concerns, a bio composite made of standard fiber and polymeric resin is one of the most recent breakthroughs in the industry and establishes the current scope of experimental activity. In the engineering application, the use of composite materials is gradually growing. The matrix and fiber are the two primary segments of the composite. The availability of high-quality fiber and ease of assembly has prompted inventors all over the world to test regionally accessible low-cost yarn and determine their ability to protect grit and how much they can perform the thankful facts of great reinforced polymer composites intended for structural use. Fiber reinforced polymer compounds have everyday preferences, such as requiring less effort to create, being easier to create, and having a higher quality disparity than perfect polymer. For this reason, fiber reinforced polymer composites are used in a variety of applications as a structural material. Composite materials are mostly developed in response to technological needs. Natural fibers have recently piqued the interest of scientists and technologists due to the advantages they offer over traditional reinforcement materials, and the creation of bio fiber composites has been a hot topic in recent years. The present work spotlight on study of mechanical properties of banana fiber/epoxy resin composite at 30%, 40% and 50% volume fractions of banana fiber and different fiber direction 00, 450 & 900.The mechanical property like tensile strength is experimentally evaluated.

Development of Creep Test Method for Thermoplastic Fiber-Reinforced Polymer Composite Tubes Under Pure Hoop Loading Condition

2019 ◽  
Author(s):  
Hai G. M. Doan ◽  
Hossein Ashrafizadeh ◽  
Pierre Mertiny
Keyword(s):  
Creep Behavior ◽  
Axial Loading ◽  
Test Method ◽  
Image Correlation ◽  
Fiber Reinforced Polymer ◽  
Time Dependent ◽  
Loading Conditions ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Dependent Behavior

Abstract Piping made from thermoplastic fiber reinforced polymer composites (TP-FRPCs) is receiving increasing attention in the oil and gas industry. Creep and time-dependent behavior is one of the main factors defining the service life of TP-FRPC structures. The lifetime and time-dependent behavior of TP-FRPC structures can be predicted using simulation tools, such as finite element analysis, to aid in the design optimization by modeling the long-term behavior of the material. Composite material time-dependent properties are required inputs for such models. While there is previous research available on creep testing of TP-FRPCs in laminate geometry, such tests may not enable accurate determination of the composite properties due to edge effects. On the other hand, coupons with tubular geometry not only provide improved load distribution between the fibers and matrix with minimal end effects, they also enable certain loading conditions experienced during typical piping operations such as internal pressure. In this study, a testing method to capture the creep behavior of tubular TP-FRPC specimens subjected to multi-axial loading conditions was developed. Tubular coupons were prototyped by an automated tape placement process. Strain was measure using digital image correlation technique and strain gauges. The development of the test setup forms the foundation for further testing of tubular TP-FRPC coupons at different multi-axial loading conditions. As a preliminary test, the creep behavior of a TP-FRPC tube subjected to pure hoop stress condition was evaluated using the developed testing process.

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