scholarly journals Flexural and Shear Tests on Reinforced Concrete Bridge Deck Slab Segments with a Textile-Reinforced Concrete Strengthening Layer

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4210 ◽  
Author(s):  
Viviane Adam ◽  
Jan Bielak ◽  
Christian Dommes ◽  
Norbert Will ◽  
Josef Hegger
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Large Scale ◽  
Shear Failure ◽  
Bridge Deck ◽  
High Strength ◽  
Shear Capacity ◽  
Strengthening Effect ◽  
Textile Reinforced Concrete ◽  
Carbon Fibre Reinforced Polymer

Many older bridges feature capacity deficiencies. This is mainly due to changes in code provisions which came along with stricter design rules and increasing traffic, leading to higher loads on the structure. To address capacity deficiencies of bridges, refined structural analyses with more detailed design approaches can be applied. If bridge assessment does not provide sufficient capacity, strengthening can be a pertinent solution to extend the bridge’s service lifetime. For numerous cases, applying an extra layer of textile-reinforced concrete (TRC) can be a convenient method to achieve the required resistance. Here, carbon fibre-reinforced polymer reinforcement together with a high-performance mortar was used within the scope of developing a strengthening layer for bridge deck slabs, called SMART-DECK. Due to the high tensile strength of the carbon and its resistance to corrosion, a thin layer with high strength and low additional dead load can be realised. While the strengthening effect of TRC for slabs under flexural loading has already been investigated several times, the presented test programme also covered increase in shear capacity, which is the other crucial failure mode to be considered in design. A total of 14 large-scale tests on TRC-strengthened slab segments were tested under static and cyclic loading. The experimental study revealed high increases in capacity for both bending and shear failure.

scholarly journals Mechanical Properties of High-Strength High-Performance Reinforced Concrete Shaft Lining Structures in Deep Freezing Wells

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Shilong Peng ◽  
Chuanxin Rong ◽  
Hua Cheng ◽  
Xiaojian Wang ◽  
Mingjing Li ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Shear Failure ◽  
High Performance Concrete ◽  
High Strength ◽  
Strength Criterion ◽  
Hydraulic Pressure ◽  
Element Analysis ◽  
Deep Freezing ◽  
Shaft Lining

As coal resources must be mined from ever deeper seams, high-strength, high-performance concrete shaft linings are required to resist the load of the soil surrounding the deep freezing well. In order to determine the optimal concrete mix for the unique conditions experienced by such high-strength high-performance reinforced concrete shaft lining (HSHPRCSL) structures in deep freezing wells, an experimental evaluation of scaled HSHPRCSL models was conducted using hydraulic pressure load tests. It was observed that as the specimens ruptured, plastic bending of the circumferential reinforcement occurred along the failure surface, generated by compression-shear failure. These tests determined that HSHPRCSL capacity was most affected by the ultimate concrete uniaxial compressive strength and the thickness-diameter ratio and least affected by the reinforcement ratio. The experimental results were then used to derive fitting equations, which were compared with the results of theoretical expressions derived using the three-parameter strength criterion for the ultimate bearing capacity, stress, radius, and load in the elastic and plastic zones. The proposed theoretical equations yielded results within 8% of the experimentally fitted results. Finally, the finite element analysis method is used to verify the abovementioned results, and all errors are less than 12%, demonstrating reliability for use as a theoretical design basis for deep HSHPRCSL structures.

scholarly journals Flexural Performance of Prefabricated Ultra-High-Strength Textile Reinforced Concrete (UHSTRC): An Experimental and Analytical Investigation

Buildings ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 68
Author(s):  
Egodawaththa Ralalage Kanishka Chandrathilaka ◽  
Shanaka Kristombu Baduge ◽  
Priyan Mendis ◽  
Petikirige Sadeep Madhushan Thilakarathna
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
High Strength ◽  
Analytical Investigation ◽  
Experimental Program ◽  
Textile Reinforced Concrete ◽  
Load Bearing ◽  
Mesh Density ◽  
Potential Improvement ◽  
Analytical Program

Textile Reinforced Concrete (TRC) is a prefabricated novel lightweight high-performance composite material that can be used as a load-bearing or non-load-bearing component of prefabricated buildings. Making TRC with Ultra-High-Strength Concrete (UHSC) (≥100 MPa) can be considered as a potential improvement method to further enhance its properties. This paper investigated the performance of Ultra-High-Strength Textile Reinforced Concrete (UHSTRC) under flexural loading. A detailed experimental program was conducted to investigate the behavior of UHSC on TRC. In the experimental program, a sudden drop in load was observed when the first crack appeared in the UHSTRC. A detailed analytical program was developed to describe and understand such behavior of UHSTRC found in experiments. The analytical program was found to be in good agreement with the experimental results and it was used to carry out an extensive parametric study covering the effects of the number of textile layers, textile material, textile mesh density, and UHSTRC thickness on the performance of UHSTRC. Using a high number of textile layers in thin UHSTRC was found to be more effective than using high-thickness UHSTRC. The high modulus textile layers effectively increase the performance of UHSTRC.

scholarly journals Experimental investigation of reinforced concrete beams with and without CFRP wrapping

2012 ◽  
Vol 20 (3) ◽  
pp. 15-26
Author(s):  
K.V. Venkatesha ◽  
S.V. Dinesh ◽  
K. Balaji Rao ◽  
B.H. Bharatkumar ◽  
S.R. Balasubramanian ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Failure Mode ◽  
Shear Failure ◽  
Shear Capacity ◽  
Reinforced Concrete Beams ◽  
Experimental Investigations ◽  
Flexural Failure ◽  
Carbon Fibre Reinforced Polymer ◽  
Fibre Reinforced Polymer ◽  
Cfrp Wrapping

AbstractThis paper presents the results of experimental investigations on six reinforced concretebeams, with three different shear span-to-depth ratios, which were tested under two-pointloading. The aim of the work was to study the efficacy of Carbon Fibre Reinforced Polymer(CFRP) strips in enhancing shear capacity and/or changing the failure mode from brittleshear failure to ductile flexural failure. The results of the study indicate that while thereis a marginal increase in first crack and ultimate loads, it is possible to achieve a changein the failure mode, and the monitored strain gauge data can be used to explain the failurepattern observed.

scholarly journals High-Strength Concrete Circular Columns with TRC-TSR Dual Internal Confinement

Buildings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 218
Author(s):  
Rami Eid ◽  
Avi Cohen ◽  
Reuven Guma ◽  
Eliav Ifrach ◽  
Netanel Levi ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
High Strength Concrete ◽  
Large Scale ◽  
Load Capacity ◽  
High Strength ◽  
Construction Method ◽  
Textile Reinforced Concrete ◽  
Rc Columns ◽  
Strength Concrete ◽  
Ductile Behavior

The standard requirements for transverse steel reinforcement (TSR) confinement in reinforced-concrete (RC) columns are mainly to provide the following: ductile behavior, minimum axial load capacity of the column’s core, and prevention of longitudinal bars buckling. It is well-known that the passive confinement due the TSR action is less effective in high-strength concrete (HSC) compared to normal-strength concrete (NSC). Therefore, the TSR amounts required by the standards for HSC columns are high, and in some cases, especially in the lower stories columns of high-rise buildings, are impractical. This paper presents a new construction method using textile-reinforced concrete (TRC) as internal confinement together with reduced TSR amounts. Moreover, comparison of the proposed method with RC columns casted in fiber-reinforced polymer (FRP) stay-in-place forms as additional external confinement, is presented. Eleven large-scale column specimens were tested under axial compression. The results give an insight on the application feasibility of the proposed construction method. It is shown that the TRC-TSR dual internal confinement action can be an option to reduce the standard required TSR amounts while maintaining similar levels of ductile behavior.

A REVIEW TO PUNCHING SHEAR CAPACTY OF NORMAL AND HIGH PERFORMANCE FIBER CEMENTIOUSE COMPOSITES

2021 ◽  
Vol 25 (Special) ◽  
pp. 4-115-4-126
Author(s):  
Liwaa Abd Alhussen ◽  
◽  
Layth A. Al-jaberi ◽  
Ra’id F. Abbas ◽  
◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Shear Failure ◽  
High Performance Concrete ◽  
Shear Capacity ◽  
Punching Shear ◽  
Concrete Slabs ◽  
Slab Thickness ◽  
Shear Stresses ◽  
Reinforced Concrete Slabs

The reaction of column to flat slabs may cause what is known as “punching shear stresses” when the stress is normally concentrated within the perimeter around the loaded area. In general, the reinforced concrete slabs are not designed for any shear failure due to the sudden nature of this type of failure. Many solutions can be followed to overcome such issue like increasing the depth of slab and diameter of columns. Increasing the slab thickness may add extensive dead loads and can breaks the economy justifications of this structural member. On the other hand, increasing the diameter of any column may un accepted due to architectural purposes. The high performance concrete is such type of concrete that illustrate high levels of mechanical performance “structural behavior as a consequence” if compared with normal concrete. Due to that, the high performance concrete may give good alternative an exceeds the problem of punching as a result. The basic aim of this study is to propose a brief review regarding this field of research. However, this study is divided to three parts, the first is devoted to view a suitable background about the punching shear capacity of traditional concrete slabs. The second part is registered to view the past experience in reinforced concrete slabs punching capacity and have steel fibers while the second part is devoted to present the state of art concerning the punching shear of high performance concrete slabs.

scholarly journals Structural Behavior of Large-Scale I-Beams with Combined Textile and CFRP Reinforcement

2020 ◽  
Vol 10 (13) ◽  
pp. 4625 ◽  
Author(s):  
Jan Bielak ◽  
Maximilian Schmidt ◽  
Josef Hegger ◽  
Frank Jesse
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
Large Scale ◽  
Concrete Strength ◽  
Limit State ◽  
Shear Capacity ◽  
Flexural Behavior ◽  
Ultimate Limit State ◽  
Full Potential ◽  
Line Load

With the innovative composite material carbon-reinforced concrete, thin-walled, high-performance components can be realized. A combination of carbon fiber reinforced polymer (CFRP) bars and non-metallic textile grids is advantageous as it exploits the full potential of the high-performance materials to reduce dead loads, increases durability, and extends lifespan. For new components with such mixed reinforcement, applicable design concepts and engineering rules are necessary to accurately determine the structural and deformation behavior. To validate models and detailing rules previously developed, three large carbon reinforced concrete I-beams were designed and tested to failure with a realistic line load. CFRP bars served as principal bending reinforcement, whereas shear and flange reinforcement consisted of textile grids. Results showed that existing models for bending using variation of strain distribution as well as non-linear finite-element analysis predicted the flexural behavior of structural components with mixed reinforcement in ultimate limit state (ULS) appropriately. Yet, calculation of shear capacity requires further studies to determine textile reinforcement contribution and estimate reduction for concrete strength in reinforced compression struts. For serviceability limit state (SLS), three methods for determination of deflection delivered good results. In future, a rethinking is required with regard to the ductility and robustness of CFRP-reinforced concrete components. In this respect, pronounced cracking as well as the large ultimate strain and deflection compensate for the lacking yield capacity of the reinforcement.

scholarly journals Influence of Patching on the Shear Failure of Reinforced Concrete Beam without Stirrup

2021 ◽  
Vol 6 (7) ◽  
pp. 97
Author(s):  
Stefanus Adi Kristiawan ◽  
Halwan Alfisa Saifullah ◽  
Agus Supriyadi
Keyword(s):  
Reinforced Concrete ◽  
Shear Failure ◽  
Numerical Study ◽  
Unsaturated Polyester ◽  
Reinforced Concrete Beam ◽  
Concrete Cover ◽  
Shear Capacity ◽  
Rc Beam ◽  
Shear Span ◽  
Shear Cracking

Deteriorated concrete cover, e.g., spalling or delamination, especially when it occurs at the web of a reinforced concrete (RC) beam within the shear span, can reduce the shear capacity of the beam. Patching of this deteriorated area may be the best option to recover the shear capacity of the beam affected. For this purpose, unsaturated polyester resin mortar (UPR mortar) has been formulated. This research aims to investigate the efficacy of UPR mortar in limiting the shear cracking and so restoring the shear capacity of the deteriorated RC beam. The investigation is carried out by an experimental and numerical study. Two types of beams with a size of 150 × 250 × 1000 mm were prepared. The first type of beams was assigned as a normal beam. The other was a beam with a cut off in the non-stirrup shear span, which was eventually patched with UPR mortar. Two reinforcement ratios were assigned for each type of beams. The results show that UPR mortar is effective to hamper the propagation of diagonal cracks leading to increase the shear failure load by 15–20% compared to the reference (normal) beam. The increase of shear strength with the use of UPR mortar is consistently confirmed at various reinforcement ratios.

scholarly journals Resistance of an Optimized Ultra-High Performance Fiber Reinforced Concrete to Projectile Impact

Buildings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 63
Author(s):  
Anna L. Mina ◽  
Michael F. Petrou ◽  
Konstantinos G. Trezos
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
High Performance Concrete ◽  
High Strength ◽  
Fiber Reinforced Concrete ◽  
Steel Fibers ◽  
Fiber Reinforced ◽  
Depth Of Penetration ◽  
Projectile Impact ◽  
High Performance Fiber

The scope of this paper is to investigate the performance of ultra-high performance fiber reinforced concrete (UHPFRC) concrete slabs, under projectile impact. Mixture performance under impact loading was examined using bullets with 7.62 mm diameter and initial velocity 800 m/s. The UHPFRC, used in this study, consists of a combination of steel fibers of two lengths: 6 mm and 13 mm with the same diameter of 0.16 mm. Six composition mixtures were tested, four UHPFRC, one ultra-high performance concrete (UHPC), without steel fibers, and high strength concrete (HSC). Slabs with thicknesses of 15, 30, 50, and 70 mm were produced and subjected to real shotgun fire in the field. Penetration depth, material volume loss, and crater diameter were measured and analyzed. The test results show that the mixture with a combination of 3% 6 mm and 3% of 13 mm length of steel fibers exhibited the best resistance to projectile impact and only the slabs with 15 mm thickness had perforation. Empirical models that predict the depth of penetration were compared with the experimental results. This material can be used as an overlay to buildings or to construct small precast structures.

Verstärkung für Fahrbahnplatten von Massivbrücken aus Textilbeton: Versuche zur Realisierung eines Demonstrators/Strengthening of Solid Bridge Deck Slabs with Textile Reinforced Concrete: Demonstrator Tests

Bauingenieur ◽  
2020 ◽  
Vol 95 (03) ◽  
pp. 85-95
Author(s):  
Viviane Adam ◽  
Norbert Will ◽  
Josef Hegger
Keyword(s):  
Reinforced Concrete ◽  
Bridge Deck ◽  
Textile Reinforced Concrete ◽  
Deck Slabs ◽  
Bridge Deck Slabs ◽  
Solid Bridge

Zusammenfassung Verkehrssteigerungen erhöhen die Anforderungen an den Brückenbestand. In einem vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Verbundprojekt wurde eine dünne Ergänzungsschicht aus Textilbeton – Smart-Deck – für Brückenfahrbahnplatten mit drei Eigenschaften entwickelt: Feuchtemonitoring, präventiver kathodischen Korrosionsschutz und Erhöhung der Tragfähigkeit. Am Institut für Massivbau der RWTH Aachen (IMB) wurde die Verstärkungswirkung in Hinblick auf die Biege- und Querkrafttragfähigkeit untersucht. Nach einigen Laborversuchen zur Findung geeigneter Materialkombinationen und gezielten Untersuchung der oben genannten Funktionen der carbonbewehrten Zusatzschicht wurde ein erster Demonstrator realisiert, an dem die baustellengerechte Herstellung von Smart-Deck und weiterhin die nach realitätsnaher Herstellung erreichbaren Funktionen überprüft werden konnten. Im nachfolgenden Beitrag werden die experimentellen Untersuchungen vorgestellt, über die der Beitrag von Smart-Deck zur Tragfähigkeit der Demonstratorplatte ermittelt werden konnte. Dazu wurden Streifen mit unterschiedlichem Biegezugbewehrungsgrad entnommen und am IMB mit variierenden Laststellungen getestet.

Sign in / Sign up

Export Citation Format

Share Document