Stress Field Design of Reinforced Concrete Members with Circular Cross Sections

2002 ◽  
Vol 12 (1) ◽  
pp. 36-39 ◽  
Author(s):  
Joseph Schwartz
Keyword(s):  
Reinforced Concrete ◽  
Stress Field ◽  
Cross Sections ◽  
Concrete Members

Verification and Validation of Corbels Strengthened by Unbonded Tendons and Bars

2020 ◽  
Vol 309 ◽  
pp. 157-162
Author(s):  
Lukáš Bobek ◽  
Lukáš Juříček ◽  
Michal Číhal ◽  
Jaromír Kabeláč ◽  
Michael Konečný
Keyword(s):  
Reinforced Concrete ◽  
Stress Field ◽  
Experimental Validation ◽  
Field Method ◽  
Load Bearing Capacity ◽  
Concrete Members ◽  
Unbonded Tendons ◽  
Independent Analysis ◽  
Real Behavior ◽  
Stiffening Effect

Reinforced corbels are frequently used in industrial halls. A number of existing corbels are prestressed by unbonded tendons or bars in order to increase their load-bearing capacity, decrease the deflections and restrain cracks spreading. The goal of the project was experimental validation of the reinforced concrete corbel strengthened using unbonded tendons via CSFM (Compatible Stress Field Method). The method is based on materially nonlinear calculation considering the tension stiffening effect of rebars and compression softening of concrete. These effects and other assumptions implemented in CSFM capture real behavior of reinforced concrete members. Besides, CSFM is verified using an independent analysis, which is based on similar assumptions as those in Compatible Stress Field Method.

scholarly journals ELASTIC-PLASTIC FRACTURE ANALYSIS OF STRUCTURAL COLUMNS

2006 ◽  
Vol 12 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Abdesselam Zergua ◽  
Mohamed Naimi
Keyword(s):  
Reinforced Concrete ◽  
Cross Sections ◽  
Correlation Study ◽  
Flow Rule ◽  
Elastic Plastic ◽  
Concrete Members ◽  
Proposed Model ◽  
Compression Region ◽  
Frame Work ◽  
Compressive Axial Load

This research is achieved in the general frame‐work of the study of the concrete behaviour. It has for objective the development of a numerical tool able to predict the behaviour of reinforced concrete columns with circular and square cross‐sections under an increasing compressive axial load. The concrete behaviour is assumed as elastic‐plastic model with an associated flow rule in compression region and as elastic with tension stiffening behaviour in the tension region. Two yield surfaces have been taken into account according to the Drucker‐Prager and Rankine failure criterions. However, the reinforcing steel is assumed as an elastic strain hardening model. A finite element method using solid cube elements for concrete, and bar elements for the reinforcement have been used. Correlation study between numerical and experimental results is conducted with the objective to establish the validity of the proposed model and identify the significance of the transverse reinforcement volumetric ratio effect on the response of reinforced concrete members. Good agreement has been observed in comparing these results.

scholarly journals Efficiency of Stress-Strain Models of Confined Concrete With and Without Steel Jacketing to Reproduce Experimental Results

2016 ◽  
Vol 10 (1) ◽  
pp. 65-86 ◽  
Author(s):  
G. Campione ◽  
L. Cavaleri ◽  
M.F. Ferrotto ◽  
G. Macaluso ◽  
M. Papia
Keyword(s):  
Reinforced Concrete ◽  
Cross Sections ◽  
Constitutive Law ◽  
Confined Concrete ◽  
Good Prediction ◽  
Existing Buildings ◽  
Combined System ◽  
Concrete Members ◽  
External Reinforcement ◽  
Strength And Deformation

The improvement and the capacity assessment of existing buildings has become the main topic of the last years so that different studies can be found devoted to damaged structures or structures not having a capacity compatible with the safety levels of the actual codes. Reinforced concrete framed structure buildings represent a conspicuous rate of the existing constructions so many efforts are addressed to them. Referring to this type of buildings, a good prediction of strength and deformation capacity requests models able to interpret the constitutive law of concrete confined by internal reinforcement or by eventual external reinforcement applied to increase capacity of cross-sections. Considering that one of the techniques much diffused for the improvement of the capacity of reinforced concrete members is the steel jacketing by the combined system of angles and battens, models able to predict the real contribution of this kind of intervention are desirable. In this connection the paper discusses the different confined concrete models available in the literature, analyzing all the characteristics and comparing the σ-ε constitutive laws for different type of RC cross sections. Also, an experimental campaign aimed to the validation of the above models is presented. Through the paper, the results of tests on columns reinforced with steel jacketing are described and the reliability of some costitutive laws for concrete confined by steel jacketing is examined.

Deflection of GFRP-reinforced concrete beams

2021 ◽  
pp. 002199832110029
Author(s):  
Katarína Gajdošová ◽  
Róbert Sonnenschein ◽  
Stanislav Blaho
Keyword(s):  
Reinforced Concrete ◽  
Cross Sections ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Bending Test ◽  
Fiber Reinforced Polymers ◽  
Concrete Members ◽  
Glass Fiber Reinforced ◽  
Gfrp Reinforcement

This paper presents an investigation of the performance of concrete beams reinforced with glass fiber-reinforced polymers (GFRP) under short-term loading. A total of six specimens with rectangular cross-sections (75 mm in height and 150 mm in width) were tested under a four-point bending test to failure. Each specimen was reinforced with two GFRP bars with diameters of 8 mm. The results of this study demonstrated the behavior of GFRP-reinforced concrete members and a validation of the available calculation methods for the deflection of these members and assumed possibilities of the use of a GFRP reinforcement over the long term. The results of the study presented show a very good agreement of an experimentally measured and theoretically calculated instantaneous deflection when using the approaches in the European and American standards. In calculations of long-term deflections, the results are highly inconsistent and seem to be quite overestimated in some cases. The study shows the necessity of real-time long-term measurements to demonstrate the real deformations to be assumed during design of structures reinforced with GFRP reinforcement.

scholarly journals Effect of stirrup type on shear capacity of reinforced concrete members with circular cross section

2020 ◽  
Vol 156 ◽  
pp. 05022
Author(s):  
Sri Hartati Dewi ◽  
Rendy Thamrin ◽  
Zaidir ◽  
Taufik
Keyword(s):  
Reinforced Concrete ◽  
Cross Sections ◽  
Circular Cross Section ◽  
Shear Capacity ◽  
Shear Behaviour ◽  
Test Results ◽  
Flexural Mode ◽  
Concrete Members ◽  
Monotonic Loads ◽  
Test Result

An experimental study of shear behaviour of reinforced concrete members with solid circular cross sections is presented. The test variables were ratio of longitudinal reinforcement and type of stirrups. The test was carried out on nine beams. Three beams were designed without stirrups, three with closed hoop stirrups, and the other with spiral stirrups. All tested beams were subjected to two-point monotonic loads. The test results showed that all beams without stirrups failed due to the shear force. Beams with hoop or spiral stirrups failed in flexural mode. The flexural capacity of beams with hoops and spiral stirrups was similar but the beams with spiral stirrups showed a slightly higher ductility. Analytical predictions showed that the chosen numerical model predicted the test result with good accuracy.

EXPERIMENTAL INVESTIGATION ON STRENGTHENING OF REINFORCED CONCRETE COLUMNS WITH CARBON CONCRETE COMPOSITE

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Klaus Holschemacher ◽  
Dennis Messerer ◽  
Wladislaw Polienko
Keyword(s):  
Reinforced Concrete ◽  
Carbon Fiber ◽  
Bearing Capacity ◽  
Cross Sections ◽  
Concrete Columns ◽  
Experimental Program ◽  
Load Bearing Capacity ◽  
Reinforced Concrete Columns ◽  
Load Bearing ◽  
Concrete Members

The application of textile reinforced concrete is well-approved technique for strengthening of reinforced concrete members. When using carbon fiber meshes and carbon fiber reinforced polymer bars as reinforcement, this material is called carbon concrete composite. Based on the outstanding properties of carbon fibers, carbon concrete composite is characterized by high bending and tensile strength, and good durability. Therefore, carbon concrete composite is increasingly applied as replacement for ordinary steel bar or steel mesh reinforced concrete. It is favorable building material for production of new buildings and for strengthening of existing reinforced concrete members. In the context of strengthening of existing reinforced concrete columns, it is a usual procedure to cover the member’s surface with a thin layer of carbon concrete composite aiming on reduction of lateral strains of the core concrete when load is increasing. The result is an increased load-bearing capacity of the strengthened column. However, there is insufficient knowledge about the influence of curvature of the carbon meshes in circular cross-sections and in the corners of rectangular cross-sections on their load-bearing capacity. For this reason, an experimental program started to study the influence of curvature, number and type of mesh layers and specimen dimensions on structural behavior of strengthened columns under axial loading. As main outcome it can be stated that besides the curvature other parameters like yarn properties are of essential importance.

Sign in / Sign up

Export Citation Format

Share Document