Behavior of Glulam Columns Reinforced by Near-Surface-Mounted CFRP Laminates under Eccentric Compression Loading

2016 ◽  
Vol 142 (11) ◽  
pp. 04016109
Author(s):  
Weidong Lu ◽  
Lu Wang ◽  
Jianjin Wu ◽  
Weiqing Liu ◽  
Huifeng Yang ◽  
...  
Keyword(s):  
Near Surface ◽  
Compression Loading ◽  
Cfrp Laminates ◽  
Eccentric Compression ◽  
Near Surface Mounted

scholarly journals Bond Behaviour of Near-Surface Mounted Strips in RC Beams—Experimental Investigation and Numerical Simulations

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4362
Author(s):  
Renata Kotynia ◽  
Hussien Abdel Baky ◽  
Kenneth W. Neale
Keyword(s):  
Concrete Strength ◽  
Element Model ◽  
Steel Reinforcement ◽  
Reinforcement Ratio ◽  
Experimental Program ◽  
Fe Model ◽  
Bond Behaviour ◽  
Near Surface ◽  
Cfrp Laminates ◽  
Near Surface Mounted

This paper presents an investigation of the bond mechanism between carbon fibre reinforced polymer (CFRP) laminates, concrete and steel in the near-surface mounted (NSM) CFRP-strengthened reinforced concrete (RC) beam-bond tests. The experimental program consisting of thirty modified concrete beams flexurally strengthened with NSM CFRP strips was published in. The effects of five parameters and their interactions on the ultimate load carrying capacities and the associated bond mechanisms of the beams are investigated in this paper with consideration of the following investigated parameters: beam span, beam depth, longitudinal tensile steel reinforcement ratio, the bond length of the CFRP strips and compressive concrete strength. The longitudinal steel reinforcement was cut at the beam mid-span in four beams to investigate a better assessment of the influence of the steel reinforcement ratio on the bond behaviour of CFRP to concrete bond behaviour. The numerical analysis implemented in this paper is based on a nonlinear micromechanical finite element model (FEM) that was used for investigation of the flexural behaviour of NSM CFRP-strengthened members. The 3D model based on advanced CFRP to concrete bond responses was introduced to modelling of tested specimens. The FEM procedure presents the orthotropic behaviour of the CFRP strips and the bond response between the CFRP and concrete. Comparison of the experimental and numerical results revealed an excellent agreement that confirms the suitability of the proposed FE model.

Study on flexural behaviour of glulam beams reinforced by Near Surface Mounted (NSM) CFRP laminates

2015 ◽  
Vol 91 ◽  
pp. 23-31 ◽  
Author(s):  
Weidong Lu ◽  
Zhibin Ling ◽  
Qifan Geng ◽  
Weiqing Liu ◽  
Huifeng Yang ◽  
...  
Keyword(s):  
Flexural Behaviour ◽  
Near Surface ◽  
Cfrp Laminates ◽  
Near Surface Mounted

Flexural Behavior of near Surface Mounted CFRP Bars Strengthened Reinforced Concrete Beams

2012 ◽  
Vol 535-537 ◽  
pp. 1702-1710 ◽  
Author(s):  
Shuaib H. Ahmad ◽  
Abdullah Bin Najm ◽  
Antonio Naani
Keyword(s):  
Reinforced Concrete ◽  
Analytical Model ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Flexural Behavior ◽  
Rc Beams ◽  
Near Surface ◽  
Rc Structures ◽  
Cfrp Laminates ◽  
Near Surface Mounted

In recent decades, use of fibre reinforced polymers (FRP) materials has become very popular for strengthening / re-strengthening of reinforced concrete (RC) structures. This includes flexural and shear strengthening of RC structural members such as slabs, beams and columns.In this study, a computerized analytical model is presented to predict the load-deflection response of flexure critical RC beams externally strengthened with near surface mounted (NSM) CFRP laminates. The analyical model utilizes constitutive material properties of concrete, reinforcing steel, CFRP laminate materials, strain compatibility, sectional analysis to develop moment-curvature relationships, which then are used to generate the load-rotations and load-deflection of the flexure critical RC Beams strengthend with NSM CFRP laminates. For validation of the analytical model, the predictions of the analytical model are compared with the experimental results of flexure critical RC beams strengthened with NSM CFRP laminates and the comparisons are judged to be good.As a part of the experimental investigation of this study, a series of 18 full scale beams Reinforced Concrete Beams strengthened with carbon fiber reinforced polymer (CFRP) laminates will be tested in flexure and shear. The results of flexural tests will be analyzed and compared with the predictions of the analytical model.

scholarly journals New Shear Strengthening Configurations of Near-Surface-Mounted CFRP Laminates for RC Beams

2016 ◽  
Vol 113 (6) ◽  
Author(s):  
Joaquim A.O. Barros ◽  
Salvador J. E. Dias ◽  
Hadi Baghi ◽  
A. Ventura-Gouveia
Keyword(s):  
Rc Beams ◽  
Shear Strengthening ◽  
Near Surface ◽  
Cfrp Laminates ◽  
Near Surface Mounted

scholarly journals Torsional strengthening of thin-walled tubular reinforced concrete structures using NSM-CFRP laminates: Experimental work

2019 ◽  
Author(s):  
Chandan C. Gowda ◽  
Joaquim A. O. Barros ◽  
Maurizio Guadagnini
Keyword(s):  
Reinforced Concrete ◽  
Limited Attention ◽  
Full Potential ◽  
Box Girders ◽  
Reinforced Polymers ◽  
Near Surface ◽  
Cfrp Laminates ◽  
Near Surface Mounted ◽  
Thin Walled ◽  
Nsm Technique

<p>Torsional strengthening of thin walled tubular reinforced concrete elements, such as bridge box girders and spandrel beams, has received only limited attention, and investigations generally focus on the use of conventional strengthening methods such as span shortening, steel encasing, member enlargement, shotcrete etc. However, research on the use of innovative fibre reinforced polymers (FRP) as near surface mounted (NSM) reinforcement for torsional strengthening is still very limited and more work should be undertaken to examine the full potential of the NSM technique over more traditional solutions. The current paper assesses experimentally, four different strengthening configurations using NSM technique applied on three faces of two beams using straight CFRP laminates, and on four faces of two beams using special L-CFRP laminates.</p><p>The results show that the proposed strengthening configurations can effectively control crack propagation and increase the torsional moment carrying capacity of the RC element, thus resulting in increased performance and durability.</p>

scholarly journals Activated Ductile CFRP NSMR Strengthening

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2821
Author(s):  
Jacob Wittrup Schmidt ◽  
Christian Overgaard Christensen ◽  
Per Goltermann ◽  
José Sena-Cruz
Keyword(s):  
Failure Modes ◽  
Elastic Response ◽  
Applied Theory ◽  
Strengthening Effect ◽  
The Novel ◽  
Near Surface ◽  
Linear Elastic ◽  
Near Surface Mounted ◽  
High Elongation ◽  
Strengthened Beam

Significant strengthening of concrete structures can be obtained when using adhesively-bonded carbon fiber-reinforced polymer (CFRP) systems. Challenges related to such strengthening methods are; however, the brittle concrete delamination failure, reduced warning, and the consequent inefficient use of the CFRP. A novel ductile near-surface mounted reinforcement (NSMR) CFRP strengthening system with a high CFRP utilization is introduced in this paper. It is hypothesized that the tailored ductile enclosure wedge (EW) end anchors, in combination with low E-modulus and high elongation adhesive, can provide significant strengthening and ductility control. Five concrete T-beams were strengthened using the novel system with a CFRP rod activation stress of approximately 980 MPa. The beam responses were compared to identical epoxy-bonded NSMR strengthened and un-strengthened beams. The linear elastic response was identical to the epoxy-bonded NSMR strengthened beam. In addition, the average deflection and yielding regimes were improved by 220% and 300% (average values), respectively, with an ultimate capacity comparable to the epoxy-bonded NSMR strengthened beam. Reproducible and predictable strengthening effect seems obtainable, where a good correlation between the results and applied theory was reached. The brittle failure modes were prevented, where concrete compression failure and frontal overload anchor failure were experienced when failure was initiated.

Sign in / Sign up

Export Citation Format

Share Document