Bond-Slip Behavior between Stainless Steel Rebars and Concrete

In recent years, as a result of the large-scale use of stainless steel bars in production and life, people’s demand for stainless steel bars has increased. However, existing research information on stainless steel bars is scant, especially the lack of research on the mechanical properties of duplex stainless steel bars and the bonding properties of duplex stainless steel bars to concrete. Therefore, this paper selects 177 duplex stainless steel bars with different diameters for room temperature tensile test, and then uses mathematical methods to provide suggestions for the values of their mechanical properties. The test results show that the duplex stainless steel bar has a relatively high tensile strength of 739 MPa, no significant yield phase, and a relatively low modulus of elasticity of 1.43 × 105 MPa. In addition, 33 specimens were designed to study the bonding properties of duplex stainless steel bars to concrete. In this paper, the effects of concrete strength, duplex stainless steel reinforcement diameter, the ratio of concrete cover to reinforcing steel diameter, and relative anchorage length on the bond stress were investigated, and a regression model was established based on the experimental results. The results show that, with the concrete strength concrete strength from C25 to C40, the compressive strength of concrete increased by 56.1%, the bond stress increased by 27%; the relative anchorage length has been increased from 3 to 6, the relative anchorage length has doubled, and the bond stress has increased by 13%; and, the ratio of concrete cover to reinforcing steel diameter increased to a certain range on the bond stress has no significant effect and duplex stainless steel reinforcement diameter has little effect on the bond stress. The ratio of concrete cover to reinforcing steel diameter from 3.3 to 4.5 and the bond stress increased by 24.7%. A ratio of concrete cover to reinforcing steel diameter greater than 4.5 has no significant effect on the bond stress, with the average bond stress value of 20.1 MPa. The duplex stainless steel bar diameter has little effect on the bond stress for the diameters of 12 mm, 16 mm, 25 mm duplex stainless steel bar, and their average bond stress is 19.9 MPa.

Section: Introductionmentioning

confidence: 99%

Basic Mechanical Properties of Duplex Stainless Steel Bars and Experimental Study of Bonding between Duplex Stainless Steel Bars and Concrete

Cui

Wang

2021

“…Despite the higher cost of the stainless-steel material, the usage of this material is most beneficial in cases of structures with heavy traffic volumes or those exposed to such aggressive environment as was discussed for the case of the steel ASTM A1010 in a recent cost-efficiency study by Daghas et al [ 2 ]. Usage possibilities of the stainless-steel material in combination with different materials have been recently studied by Pauletta et al [ 3 ], who investigated the bond-slip behavior between stainless-steel reinforcement bars and concrete, or by Corradi et al [ 4 ], who reviewed the use of stainless-steel profiles to reinforce or repair historical wooden structures. Research is also conducted also on the enhancement of the stainless-steel corrosion resistance by Dinu et al [ 5 ], who proposed a certain improvement of the grade AISI 304 stainless steel.…”

Section: Introductionmentioning

confidence: 99%

Validation of Stainless-Steel CHS Columns Finite Element Models

Jindra

Kala

2021

Stainless-steel elements are increasingly used in a wide range of load-bearing structures due to their strength, minimal maintenance requirements, and aesthetic appearance. Their response differs from standard steels; therefore, it is necessary to choose a different procedure when creating a correct computational model. Seven groups of numerical models differing in the used formulation of elements integration, mesh density localization, nonlinear material model, and initial geometric imperfection were calibrated. The results of these advanced simulations were validated with published results obtained by an extensive experimental approach on circular hollow sections columns. With regard to the different slenderness of the cross-sections, the influence of the initial imperfection in the form of global and local loss of stability on the response was studied. Responses of all models were validated by comparing the averaged normalized ultimate loads and the averaged normalized deflections with experimentally obtained results.

“…In view of the importance of the bond between steel and concrete, many scholars have conducted extensive research. In the past few decades, many studies have proposed characteristic parameters for this complex problem [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 ]. However, due to the complexity of the bond interface, data dispersion, and other test conditions, the bond–slip constitutive relationship proposed by different scholars has certain differences and is often only applicable to specific situations.…”

Section: Introductionmentioning

confidence: 99%

Modeling Local Bond Stress–Slip Relationships of Reinforcing Bars Embedded in Concrete with Different Strengths

Tang

Cheng

2020

Although many different analytical models of local bond stress–slip have been proposed, considering the possible differences between materials in different countries, their applicability needs to be further explored. In this paper, the local bond stress–slip characteristics of reinforcing bars embedded in concrete with different strengths were experimentally studied. The experimental variables included the concrete strength (20, 40, and 60 MPa) and deformed rebar size (#4, #6, and #8). The experimental results of the bond stress–slip relationship were compared with the Euro-International Concrete Committee (CEB-Comité Euro-International du Béton)-International Federation for Prestressing (FIP-Fédération Internationale de la Précontrainte) Model Code and prediction models found in the literature. In addition, based on the test results, an empirical model of the bond stress–slip relationship was proposed. The evaluation and comparison results show that, regardless of the concrete strength grades, the predicted value calculated using the CEB-FIP Model Code will underestimate the bond strength of the specimens with different steel bar diameters. From this perspective, it is more conservative. In contrast, the proposed model can predict the test results with a reasonable accuracy.