scholarly journals Comparison of the stress-strain state of the reinforced concrete structure under various mathematical models of concrete

2018 ◽  
Vol 251 ◽  
pp. 04032
Author(s):  
Dmitriy Sidorov ◽  
Vladimir Dorozhinskiy
Keyword(s):  
Reinforced Concrete ◽  
Mathematical Models ◽  
Strain State ◽  
Concrete Structures ◽  
Seismic Action ◽  
Reinforced Concrete Structure ◽  
Reinforcing Bars ◽  
Plastic Deformations ◽  
Regulatory Documents ◽  
Structural Engineer

Nowadays, reinforced concrete structures are most often used as load-bearing elements of buildings and structures. In the case of alternating loads such as seismic action, there is accumulation of residual plastic deformations in the concrete structures, which leads to a significant complication in the calculation of structures by “standard” methods. For such problems, it is advisable to use computational complexes in which mathematical models of structural materials are implemented, which allow to describe the work of concrete and reinforcing bars for various types of impacts more properly. However, when applying such methods, the results obtained should not contradict the requirements of the existing regulatory documents, which, in the first place, the structural engineer should be guided by. Before solving more complex problems, the applied methods should be verified and analyzed for fairly simple structures and types of loads.

scholarly journals Samples of concrete of small sizes

2019 ◽  
Vol 91 ◽  
pp. 02043
Author(s):  
Andrew Varlamov ◽  
Sergey Tverskoi ◽  
Vadim Gavrilov
Keyword(s):  
Reinforced Concrete ◽  
Strain State ◽  
Concrete Structures ◽  
Small Samples ◽  
Reinforced Concrete Structures ◽  
Standard Samples ◽  
Stress Strain ◽  
Strength And Deformation ◽  
Loss Of Strength ◽  
Reference Samples

The article analyzes the sizes of concrete samples. We revealed a possibility to reduce sizes of samples. We simultaneously carried out tests of standard and small (25x25x100 mm) concrete samples. Small samples were obtained by cutting standard samples. In the course of study, the density, strength, and deformation of standard and small specimens were measured. The results are presented in tables and graphs. The strength of small samples was lower than the strength of reference samples. We identified loss of strength of the samples when cutting concrete. The average characteristics of deformation of concrete remained. Small samples are recommended for use in assessing the stress-strain state of reinforced concrete structures.

scholarly journals Bearing capacity of RC beams reinforced with high strength rebars and steel plate

2018 ◽  
Vol 230 ◽  
pp. 02003 ◽  
Author(s):  
Taras Bobalo ◽  
Yaroslav Blikharskyy ◽  
Rostyslav Vashkevich ◽  
Myhailo Volynets
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Steel Plate ◽  
Concrete Structures ◽  
High Strength ◽  
Strength Properties ◽  
Rc Beams ◽  
Reinforcing Bars ◽  
External Reinforcement ◽  
Effective Use

Nowadays, reducing the material content of not only buildings and structures in general, but also individual constructions is a topical task that can be realized through the use of high-strength concrete and reinforcement, as well as with the use of external reinforcement. The concentrated location of sheet reinforcement on the external the most tense facets of steel and concrete structures increases the operating height of the cross-section, makes it possible to more effectively use the strength properties of steel in comparison with conventional reinforced concrete, and with the same bearing capacity to economize on expenses. Composite and monolithic reinforced concrete structures with external reinforcement are used in various construction sectors around the world. This contributed to the expansion of the use of reinforced concrete for special buildings of power-engineering and hydrotechnical construction. The technical nd econom efficiency, as well as the possibility of using external rebar as formwork for monolithic concrete construction, have been proved. Therefore, there is a need for the study of structures with combined reinforcement, in which high rigidity of steel and concrete structures is combined with an effective use of high-strength reinforcing bars (rebar) without prior tension

scholarly journals Modeling Blast Loading on Buried Reinforced Concrete Structures with Zapotec

2008 ◽  
Vol 15 (2) ◽  
pp. 137-146 ◽  
Author(s):  
Greg C. Bessette
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structure ◽  
Explosive Charge ◽  
High Explosive ◽  
Concrete Structures ◽  
Blast Loading ◽  
Reinforced Concrete Structures ◽  
Reinforced Concrete Structure ◽  
Solution Approach ◽  
Coupling Algorithm

A coupled Euler-Lagrange solution approach is used to model the response of a buried reinforced concrete structure subjected to a close-in detonation of a high explosive charge. The coupling algorithm is discussed along with a set of benchmark calculations involving detonations in clay and sand.

Numerical Interpretation of Bond Between Steel and Concrete in Presence of Corrosion and Cyclic Action

2009 ◽  
Vol 417-418 ◽  
pp. 349-352 ◽  
Author(s):  
Luca Giordano ◽  
Giuseppe Mancini ◽  
Francesco Tondolo
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Stress Transfer ◽  
Experimental Tests ◽  
Radial Pressure ◽  
Mechanical Action ◽  
Concrete Cover ◽  
Reinforcing Bars ◽  
Cyclic Action ◽  
Bond Slip

Bond between steel and concrete in reinforced concrete structures plays a fundamental role. The stress transfer mechanism depends on the condition of the contact surface between the two materials, the mechanical characteristics of concrete near the rebar and on the available level of confinement. Corrosion of reinforcing bars in concrete structures modifies those three factors. Because of corrosion, on the rebar surface a granular oxide layer is present and with its expansion it generates a significant radial pressure; consequently tensile stresses grow till cracking of the concrete cover with a subsequent reduction of the confinement effect. Moreover the presence of a mechanical action modifies the resisting mechanism producing an increasing damage. In this study, a model is presented for the numerical simulation of experimental tests on r.c. ties subjected to mechanical action; furthermore some considerations on reinforced concrete ties subjected also to corrosion effect are reported. From those analyses it is possible to estimate a modified bond-slip law between the reinforcing bars and the concrete, in order to take into account the level of damage.

Experimental Evaluation of Corrosion Effect on Bond Between Steel and Concrete in Presence of Cyclic Action

2009 ◽  
Vol 417-418 ◽  
pp. 345-348 ◽  
Author(s):  
Luca Giordano ◽  
Giuseppe Mancini ◽  
Francesco Tondolo
Keyword(s):  
Reinforced Concrete ◽  
Cyclic Load ◽  
Crack Opening ◽  
Concrete Structures ◽  
Electrochemical Corrosion ◽  
Reinforced Concrete Structures ◽  
Reinforcing Bars ◽  
Cyclic Action ◽  
In Series ◽  
Ultimate Condition

Corrosion modifies the steel-concrete interface in reinforced concrete structures. The efficiency of the connection between the two materials is reduced and the structural behavior both in service and in ultimate condition is affected. Moreover in structures subjected to cyclic load, a simultaneous mechanical deterioration due to the load is present. In this work an experimental analysis on reinforced concrete structures under both cyclic load and corrosion of reinforcing bars is presented. Three couples of reinforced concrete ties are connected in series and subjected to the same stress variation in order to produce the cracking conditions and to activate the bond mechanism. However, while one of the two reinforced concrete ties is only subjected to cyclic load, the second one is also corroded using an accelerated electrochemical corrosion process. The simultaneous effect of the cyclic load and corrosion is evaluated monitoring the crack opening on the structures during the test and by means of visual inspection of the sample. The test results show the correlation between the mechanism of bond and the average level of stresses for an amplified stress range.

scholarly journals Estimation of the pull-off resistance models of reinforced concrete structures by a numerical method

2021 ◽  
Vol 350 ◽  
pp. 00011
Author(s):  
Mikalai Shalabyta ◽  
Elizabeth Matweenko ◽  
Nikifor Matweenko ◽  
Valery Rakhuba
Keyword(s):  
Numerical Modeling ◽  
Reinforced Concrete ◽  
Comparative Analysis ◽  
Strain State ◽  
Numerical Models ◽  
Tensile Force ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
New Information ◽  
Concrete Elements

Comparative analysis of calculations of calculation numerical models for pulling out embedded parts in reinforced concrete structures is carried out. Based on the results of numerical modeling, new information about the stress-strain state in reinforced concrete elements from the local action of the tensile force has been obtained.

Fuzzy uncertainty and its applications in reinforced concrete structures

2020 ◽  
Vol 18 (5) ◽  
pp. 1175-1191
Author(s):  
Utino Worabo Woju ◽  
A.S. Balu
Keyword(s):  
Reinforced Concrete ◽  
Material Properties ◽  
Concrete Structure ◽  
Concrete Structures ◽  
Fuzzy Relation ◽  
Reinforced Concrete Structures ◽  
Reinforced Concrete Structure ◽  
Intermediate Grades ◽  
Content Type ◽  
Degree Of Membership

Purpose The aim of this paper is mainly to handle the fuzzy uncertainties present in structures appropriately. In general, uncertainties of variables are classified as aleatory and epistemic. The different sources of uncertainties in reinforced concrete structures include the randomness, mathematical models, physical models, environmental factors and gross errors. The effects of imprecise data in reinforced concrete structures are studied here by using fuzzy concepts. The aim of this paper is mainly to handle the uncertainties of variables with unclear boundaries. Design/methodology/approach To achieve the intended objective, the reinforced concrete beam subjected to flexure and shear was designed as per Euro Code (EC2). Then, different design parameters such as corrosion parameters, material properties and empirical expressions of time-dependent material properties were identified through a thorough literature review. Findings The fuzziness of variables was identified, and their membership functions were generated by using the heuristic method and drawn by MATLAB R2018a software. In addition to the identification of fuzziness of variables, the study further extended to design optimization of reinforced concrete structure by using fuzzy relation and fuzzy composition. Originality/value In the design codes of the concrete structure, the concrete grades such as C16/20, C20/25, C25/30, C30/37 and so on are provided and being adopted for design in which the intermediate grades are not considered, but using fuzzy concepts the intermediate grades of concrete can be recognized by their respective degree of membership. In the design of reinforced concrete structure using fuzzy relation and composition methods, the optimum design is considered when the degree of membership tends to unity. In addition to design optimization, the level of structural performance evaluation can also be carried out by using fuzzy concepts.

On the seismic vulnerability evaluation of RC bridges exposed to corrosion

2021 ◽  
Author(s):  
Marco Zucca ◽  
Pietro Crespi ◽  
Giuseppe Pasqualato
Keyword(s):  
Reinforced Concrete ◽  
Seismic Vulnerability ◽  
Concrete Structures ◽  
Concrete Bridges ◽  
Reinforced Concrete Structures ◽  
Seismic Action ◽  
Efficient Procedure ◽  
Reinforced Concrete Bridges ◽  
Strength Capacity ◽  
Wide Range

<p>Recently, the engineering interest about the durability of existing reinforced concrete structures has significantly increased as confirmed by the conspicuous scientific literature. The results of these studies are influencing the development of new structural codes. Among the wide range of existing reinforced concrete structures, motorway viaducts stand out for their strategic relevance. Most of these structures were built between ’60 and ’70 years and, nowadays, the materials degradation phenomena are leading to strength capacity reduction, either in serviceability condition or in presence of exceptional loads such as the seismic action. In order to evaluate the degradation phenomena effects on the seismic vulnerability of motorway viaducts, this paper shows an efficient procedure to evaluate the seismic performance of reinforced concrete bridges starting from the modelling of the materials degradation, according to several scenarios, and by carrying out multimodal pushover analyses.</p>

Sign in / Sign up

Export Citation Format

Share Document