FRP-confined short concrete columns under compressive loading: experimental and modeling investigation

This paper explores the possibility to use Drucker-Prager model in Steel-Concrete composite section. Numerical simulation was conducted using finite element package to simulate the steel-concrete composite section subjected to uniaxial compressive loading. After calibration with experimental study, parametric study was conducted to evaluate the effect of the friction angle and the cohesion constant c on the stress-strain curve of composite section. Empirical relationship between the friction angle and the confined concrete compressive strength was developed and a range of cohesion constant c between 5-10 MPa was suggested for confined concrete strength range of 25 to 100 MPa, respectively.

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Experimental and numerical investigations on the size effect of moderate high-strength reinforced concrete columns under small-eccentric compression

International Journal of Damage Mechanics ◽

10.1177/1056789517699054 ◽

2017 ◽

Vol 27 (5) ◽

pp. 657-685 ◽

Cited By ~ 16

Author(s):

Liu Jin ◽

Zixing Ding ◽

Dong Li ◽

Xiuli Du

Keyword(s):

Compressive Strength ◽

Reinforced Concrete ◽

Size Effect ◽

Compressive Loading ◽

High Strength ◽

Concrete Columns ◽

Failure Behavior ◽

Reinforced Concrete Columns ◽

Failure Patterns ◽

Softening Behavior

The paper deals with an experimental investigation and numerical simulation of moderate high-strength reinforced concrete (RC) columns subjected to a small-eccentric compressive loading ( e0 = 0.25 h0). A series of tests on the behavior of 12 geometrically similar moderate high-strength reinforced concrete columns with two different stirrups ratios (i.e., 0% and 0.66%) were conducted. The maximum structural size of the square reinforced concrete columns was 800 mm. A 2D mesoscale method for the simulation of the behavior of reinforced concrete columns was established. The numerical tests on the reinforced concrete columns with larger stirrup ratios (1.2% and 2.4%) were carried out complementarily, based on the fact that the simulation results were consistent with the available test observations. The failure patterns, the nominal compressive stress–strain relationships, the nominal compressive strength, and the post-peak softening behavior of the reinforced concrete columns were studied. Furthermore, the influence of stirrups on failure behavior and size effect of the reinforced concrete columns was revealed. One can conclude that (1) the size effect exists in the nominal compressive strength of the eccentrically loaded high-strength reinforced concrete columns with the four different stirrup ratios; (2) comparison of the present test results and the “size effect law” proposed by Bažant shows good agreement; (3) the presence of stirrups improves the nominal strengths, makes the failure of columns less brittle, and weakens the size effect; and (4) the proposed mesoscale numerical method is capable of describing the mechanical behavior of eccentrically loaded reinforced concrete columns.

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Ductile Compressive Failure of Concrete Reinforced with High Strength Carbon Hybrid Composite

The Open Construction and Building Technology Journal ◽

10.2174/1874836801812010049 ◽

2018 ◽

Vol 12 (1) ◽

pp. 49-64

Author(s):

Hwai-Chung Wu ◽

Boubacar Diallo

Keyword(s):

Hybrid Composite ◽

Load Capacity ◽

Compressive Loading ◽

High Strength ◽

Plain Concrete ◽

Concrete Columns ◽

Steel Reinforced Concrete ◽

Steel Rebar ◽

High Load Capacity ◽

Very High

Background: For centuries, steel rebar has been the primary reinforcement in concrete despite its major drawbacks, such as its heavy weight, high electrical conductivity, and corrosiveness. Thus, in response to the need for better alternatives, innovative Hybrid Composite (HC) reinforcements have been developed. Objective: The focus of this paper is to investigate the performance of tubular HC reinforcements in concrete columns under axial compressive loading. Method: Concrete columns of different sizes were tested. Results and Conclusion: For the small columns, HC reinforced columns showed very high load capacity, which was more than 3 times the capacity of plain concrete. Moreover, significant ductility was achieved with an ultimate strain of up to 59%. For the large columns, HC reinforced columns showed similar load capacities, but much larger ultimate strains in comparison to the corresponding steel reinforced concrete columns.

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Assessment of Cores Using Electroacoustic Methods

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.322.214 ◽

2021 ◽

Vol 322 ◽

pp. 214-219

Author(s):

Sabina Hüblová ◽

Kristýna Hrabová ◽

Jaromír Láník ◽

Petr Cikrle

Keyword(s):

Reinforced Concrete ◽

20Th Century ◽

Compressive Loading ◽

Concrete Columns ◽

Reinforced Concrete Columns ◽

Ultimate Resistance

The paper focuses on the assessment of structures using the methods described in the new edition of the ČSN EN 1371 standard. An experiment will be conducted on cores taken from reinforced concrete columns under compressive loading up to the ultimate resistance. The concrete used to make the column should correspond to old concrete used in the second half of the 20th century. The column will be made with a deliberately created defect - such as stratification or bad compaction of the concrete. When the column is damaged, different degrees of damage to the concrete along its height occur. This can be detected by a thorough examination of cores through the ultrasonic and resonance methods.

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