scholarly journals Dynamic Characteristics of Reinforced Concrete Beams Made of Carbonate Concrete

2022 ◽  
Author(s):  
V. Belov
Keyword(s):  
Reinforced Concrete ◽  
Material Properties ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Dynamic Problems ◽  
Dynamic Stresses ◽  
Elastic Rebound ◽  
Dynamic Impacts ◽  
The Impact ◽  
Independent Parameters

Abstract. The ability of solid structures to absorb a certain part of the energy of dynamic impacts has not been properly reflected in impact theories. Meanwhile the effect of material properties on the various structures in the impact is so much that ignoring it when the solution of a large number dynamic problems makes it impossible to explain without distorting quantitatively and qualitatively, many of the actually observed phenomena, for example, equalization of dynamic stresses in places of their concentration and fluctuation of other parameters. In the article, two independent parameters for conventional reinforced concrete beams and those made of limestone concrete are compared, namely dynamic coefficient and the values of elastic rebound in impact. The effect of the reinforcement is not discussed in the paper.

Effect of cracking localization on the structural ductility of normal strength and high strength reinforced concrete beams with steel fibers

2019 ◽  
Vol 10 (4) ◽  
pp. 457-469 ◽  
Author(s):  
Avraham N Dancygier ◽  
Yuri S Karinski
Keyword(s):  
Reinforced Concrete ◽  
Transition Point ◽  
Concrete Beams ◽  
High Strength ◽  
Reinforcement Ratio ◽  
Steel Fibers ◽  
Reinforced Concrete Beams ◽  
Flexural Ductility ◽  
Ductility Ratio ◽  
The Impact

This article presents a study of cracking localization in normal and high strength concrete beams that include steel fibers and the influence of this localization on their structural ductility. It is shown that for a given fiber type and content, as the reinforcement ratio ρ decreases, the cracking localization level increases. The effect of ρ on the level of cracking localization is more pronounced for low amounts of conventional reinforcement. This range of conventional reinforcement ratio is typical of slabs and especially for the commonly thicker protective slabs. Examination of the effect of the reinforcement ratio on the flexural ductility shows that there exists a transition point below which the ductility ratio decreases with  ρ. This transition point is well above the minimum reinforcement ratio, which is required in design codes for plain reinforced concrete elements. Empirical analysis of the relation between cracking localization and ductility ratio shows that up to the same transition point, as cracking localization increases, the flexural ductility decreases. Findings of this study show that the positive effect of adding fibers on enhancing the impact resistance of slabs and beams is conflicted by their negative influence on reducing the structural ductility for low reinforcement ratios, which are typical of protective slabs.

scholarly journals Performance based design of reinforced concrete beams under impact

2010 ◽  
Vol 10 (6) ◽  
pp. 1069-1078 ◽  
Author(s):  
S. Tachibana ◽  
H. Masuya ◽  
S. Nakamura
Keyword(s):  
Reinforced Concrete ◽  
Collision Energy ◽  
Concrete Beams ◽  
Impact Load ◽  
Experimental Results ◽  
Reinforced Concrete Beams ◽  
Performance Based Design ◽  
Impact Action ◽  
The Impact ◽  
A Performance

Abstract. The purpose of this research is to collect fundamental data and to establish a performance-based design method for reinforced concrete beams under perpendicular impact load. Series of low speed impact experiments using reinforced concrete beams were performed varying span length, cross section and main reinforcement. The experimental results are evaluated focusing on the impact load characteristics and the impact behaviours of reinforced concrete beams. Various characteristic values and their relationships are investigated such as the collision energy, the impact force duration, the energy absorbed by the beams and the beam response values. Also the bending performance of the reinforced concrete beams against perpendicular impact is evaluated. An equation is proposed to estimate the maximum displacement of the beam based on the collision energy and the static ultimate bending strength. The validity of the proposed equation is confirmed by comparison with experimental results obtained by other researchers as well as numerical results obtained by FEM simulations. The proposed equation allows for a performance based design of the structure accounting for the actual deformation due to the expected impact action.

scholarly journals Stability Analysis of High-Rise Buildings by Altering the Beam Members: A Review

2021 ◽  
Vol 9 (10) ◽  
pp. 501-507
Author(s):  
Ankur Nagar
Keyword(s):  
Reinforced Concrete ◽  
Composite Beam ◽  
Concrete Beams ◽  
Tall Buildings ◽  
Reinforced Concrete Beams ◽  
Steel Beams ◽  
Lateral Loads ◽  
Rigid Frame ◽  
Lateral Rigidity ◽  
The Impact

Abstract: For buildings larger than 15 to 20 floors, a system with a clean rigid frame is not adequate because it does not provide the required lateral rigidity and causes excessive deflection of the building. These requirements are met in two ways. By introducing the effective section such as beam, column etc in to the structure. This increases the stability and rigidity of the structure, and also limits the requirement for deformation. Now days the composite beam is also used for tall buildings. The Paper present the short summery report of use of various beam elements in building to get the effective out comes to sustained under the lateral forces response. The literature review focus on the impact on the building analysis by altering the Beam Members. Reinforced Concrete Beams, Steel Beams, and Composite Beams. The articles reviewed the concept on introducing the alternating beam in the structure are effective and achieve the higher resisting capacity against the lateral loads. Keywords: Reinforced Concrete Beams, composite beam, Steel Beams, tall buildings, deformation, stability

scholarly journals Calculation of damage RC constructions according to deformation model

2020 ◽  
Vol 2020 (2) ◽  
pp. 99-106
Author(s):  
Yaroslav Blikharskyy ◽  
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Concrete Beams ◽  
Concrete Structures ◽  
Physical And Mechanical Properties ◽  
Reinforced Concrete Beams ◽  
Core Material ◽  
Deformation Model ◽  
Reinforced Concrete Structures ◽  
The Impact

This article presents results of a theoretical study of reinforced concrete beams with damaged reinforcement. The change of micro-hardness of a reinforcing rebar’s with a diameter of 20 mm of A500C steel in the radial direction is investigated and the thickness of the heat-strengthened layer is established. It is established that the thickness of the thermo-strengthened steel layer of the reinforcing bar with a diameter of 20 mm of A500C is approximately 3 mm. It is shown that the strength characteristics of this layer are on 50% higher compared to the core material of the rebar, while the plasticity characteristics are lower. The aim of the work is to determine the strength and deformability of reinforced concrete structures without damaging the reinforcement and in case of damage. Determining the impact of changes in the physical characteristics of reinforcement on the damage of reinforced concrete structures, according to the calculation to the valid norms, in accordance with the deformation model. To achieve the goal of the work, theoretical calculations of reinforced concrete beams were performed according to the deformation model, according to valid norms. This technique uses nonlinear strain diagrams of concrete and rebar and is based on an iterative method. According to the research program 3 beam samples were calculated. Among them were undamaged control sample with single load bearing reinforcement of ∅20 mm diameter – BC-1; sample with ∅20 mm reinforcement with damages about 40% without changes in the physical and mechanical properties of reinforcement – BD-2 and sample with ∅20 mm reinforcement with damages about 40% with changes in the physical and mechanical properties of reinforcement – BD-3. The influence of change of physical and mechanical characteristics of rebar’s on bearing capacity of the damaged reinforced concrete beams is established.

scholarly journals Behavior of fiber-reinforced polymer-strengthened reinforced concrete beams under static and impact loads

2016 ◽  
Vol 8 (1) ◽  
pp. 3-24 ◽  
Author(s):  
Thong M Pham ◽  
Hong Hao
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Impact Loads ◽  
Fiber Reinforced ◽  
Static Loads ◽  
Reinforced Polymer ◽  
Longitudinal Fiber ◽  
The Impact

This study investigates the behavior of fiber-reinforced polymer-strengthened reinforced concrete beams under static and impact loads. The experimental program includes six beams tested in static loads and seven beams tested against impact loads. Longitudinal fiber-reinforced polymer strips and fiber-reinforced polymer U-wraps were used to strengthen these beams. The section of four beams was modified to have a curved soffit in order to reduce the stress concentration of fiber-reinforced polymer U-wraps and provide confinement effect on longitudinal fiber-reinforced polymer strips. The experimental results showed that the proposed modification significantly increased the beam capacities as compared to their rectangular counterparts strengthened with the same amount of fiber-reinforced polymer material. In addition, this article also provides explanations and discussions on the phenomenon of shifting of the flexure failure mode under static loads to the shear–flexure failure mode under impact loads of all the beams tested in the study, as well as the proper interpretations of the measured impact forces in the tests. From the experimental results, it is recommended that the impact force and inertial force at the very early stage of an impact event should be used to design the impact resistance.

Sign in / Sign up

Export Citation Format

Share Document