Corrosion macrocell behavior of reinforcing steel in partially submerged concrete columns

In the present work, it is proposed to include in the theoretical curves of moment-curvature (m- φ) the effect of corrosion by obtaining the decrease in the area of longitudinal reinforcing steel. The corrosion depth will be obtained from the crack width and corrosion length observed in the cover concrete. With the depth of corrosion, the area of steel that is lost will be obtained and this modification will be incorporated into the theoretical procedure to elaborate the m- φ curves. The forces of the steel will be obtained from an elastoplastic model with curved hardening and the forces of the concrete with a model that considers the effect of confinement.

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The Ways to Reduce the Materials Consumption of Compressed Reinforced Concrete Elements

Materials Science Forum ◽

10.4028/www.scientific.net/msf.931.321 ◽

2018 ◽

Vol 931 ◽

pp. 321-327

Author(s):

Viktor A. Muradyan

Keyword(s):

Reinforced Concrete ◽

Bearing Capacity ◽

Concrete Columns ◽

Fracture Pattern ◽

Reinforcing Steel ◽

Optimal Parameters ◽

Reinforced Concrete Columns ◽

Concrete Elements

The article deals with the main advantages of reinforced concrete columns with recessed fittings. The method of testing the prototype columns is described. In addition, the influence of various factors on the fracture pattern and bearing capacity of such columns is explained. The standard reinforced concrete columns are given below and the optimal parameters for saving reinforcing steel are observed [1-7].

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Structural Behavior of Unbalanced Section self-compacting reinforced concrete axially Loaded columns

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.37.24088 ◽

2018 ◽

Vol 7 (4.37) ◽

pp. 127

Author(s):

Aamer Najim Abbas ◽

Nura Jasim Muhammed

Keyword(s):

Reinforced Concrete ◽

Large Deformations ◽

Concrete Columns ◽

Element Model ◽

Asymmetric Distribution ◽

Reinforcing Steel ◽

Test Results ◽

Normal Concrete ◽

Steel Bars ◽

Control Column

Eight (120 mm) square and (1 m) long reinforced concrete columns were tested under axial load to large inelastic deformations. The main purpose of this research was to investigate the behavior of column sections confined by rectilinear ties. Major variables considered in this program included: (1) Distribution of longitudinal and lateral steel, including unbalanced section due to the asymmetric distribution of reinforcing steel bars (2) type of concrete; normal concrete and self-compacting concrete. Finite element model was performed to validate the experimental results of this investigation. Test results indicate that a asymmetric distribution longitudinal bars results in desired performance of columns. Unsupported longitudinal bars and its number effective only at large deformations and result in rapid deterioration of column behavior at a later stage. There is 8.75% and 35.65% decrease in ultimate capacity under the control column, asymmetric distribution of reinforcing steel bars appears a more brittle while symmetric bars yields more elastic than brittle, it adds safety when failure happens.

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Tingkat Efisiensi Perhitungan Kolom Beton (Perbandingan PBI 1971 Dengan SNI 1991)

BENTANG : Jurnal Teoritis dan Terapan Bidang Rekayasa Sipil ◽

10.33558/bentang.v7i2.1750 ◽

2019 ◽

Vol 7 (2) ◽

pp. 79-103

Author(s):

Sri Nuryati ◽

Sigit Suwanto

Keyword(s):

Structural Analysis ◽

Concrete Columns ◽

Concrete Column ◽

Reinforcing Steel ◽

Structural Elements ◽

Steel Quality ◽

Constant Area ◽

Concrete Quality ◽

Calculation Results ◽

Manual Calculation

The collapse of a column causes the collapse of the entire building that need a large cost for repairing. Therefore, special attention is needed when planning the columns, i.e. by providing a backup strength on columns which greater than other beams and other horizontal structural elements since there is no initial warning in a press-type of collapse. This study aims to determine the efficiency of square concrete column dimensions in case of column calculations after the revision of PBI 1971 to SNI 1991 standard both by manual calculation and using the Turbo Pascal-based application. Calculation utilized the elastic method and ultimate method with the assumption that column conditions are similar as well as the column data is taken from the calculation of reinforced portal structures. Concrete columns are made rectangle with dimensions of size 35 x 35 cm and size 75 x 75 cm, concrete quality K 225, steel quality U24 (2400 kg / cm²), modulus of steel elasticity 2.1. 10⁶ kg / cm² and 5 cm thick of concrete blanket, with the assumption that structural analysis has been conducted for calculating the boundary and moment loads, assuming that the column conditions are similar. In case of the ability to retain the load and moment by the column, assuming the constant area of reinforcement in various dimensions, the results of the elastic method (PBI 1071) were smaller than the ultimate method (SK SNI 1991). The calculation results showed that the ultimate method was more efficient than the elastic method in terms of the efficiency of reinforcing steel use.

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Influence of GFRP Confinement of Reinforced Concrete Columns on the Corrosion of Reinforcing Steel in a Salt Water Environment

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0001039 ◽

2015 ◽

Vol 27 (1) ◽

pp. 04014107 ◽

Cited By ~ 7

Author(s):

B. Sena da Fonseca ◽

A. S. Castela ◽

Manuel A. G. Silva ◽

R. G. Duarte ◽

M. G. S. Ferreira ◽

...

Keyword(s):

Reinforced Concrete ◽

Salt Water ◽

Water Environment ◽

Concrete Columns ◽

Reinforcing Steel ◽

Reinforced Concrete Columns

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Optimization of reinforcing steel with genetic algorithms for the design of concrete columns

10.31224/osf.io/mwxzn ◽

2021 ◽

Author(s):

Luis Fernando Verduzco

Keyword(s):

Construction Industry ◽

Cross Sections ◽

Optimization Algorithm ◽

Structural Engineering ◽

Heuristic Algorithms ◽

Concrete Columns ◽

Reinforcing Steel ◽

Structural Elements ◽

Optimization Program ◽

Concrete Elements

Is presented hereby the creation of an optimization program for the design of reinforcing steel for any type of structural elements which may be considered as columns, pillar, pilots or dies, subjected to flexo-compression mechanic stresses for rectangular cross sections elements with the support of numeric methods and meta-heuristic algorithms for the optimization of constructions costs, particularly the Genetic algorithm, adapting such algorithms to the optimization problem so that it makes the resultant designs practical and convenient for its application in the construction industry, based on certain criteria from NTC-17 and questioning other. It will be shown how such optimization algorithm was adapted to the problem, as well as other general numeric methods for engineering and others developed specifically for structural engineering for the optimal design of this sort of concrete elements. Moreover, sensibility cost analysis of unitary construction prices are presented as well, with which the objective function for the optimization algorithm was created. At the end, results of various experiments with and without the optimization program are shown, making comparisons between different structural models regarding cost and geometry.

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