Shear strength model for RC joints, consistent with the shear design rules for prismatic members in the second-generation Eurocodes

Fardis, Michael N.

doi:10.1007/s10518-020-01000-0

Cited by 12 publications

(4 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The representative value of resistance 𝑅 𝑘 in the design Equation ( 19) is taken equal to the median. Consistently with current practice, for both the first 22 and draft second-generation Eurocode 8, 66 the seismic action effect is not amplified by a partial factor, i.e., 𝛾 𝐸 = 1.0. Factor 𝛾 𝑅 is taken proportional to the uncertainty in resistance, equal to 1.5 and 2.7, for 𝜎 ln 𝑅 = 0.2 and 0.5, respectively.…”

Section: Reliability Analysissupporting

confidence: 71%

“…The first-generation Part 3 58 also included a "seismic" shear strength model, 60 which was in line with other international proposals. [61][62][63] This model is included in the second generation Eurocode 8 56,64 in an updated 65,66 form, compatible with the shear strength model for vertical loads. Formally, all these deformation and strength models are now included in Part 1-1, 64 for displacement-based design of new structures whereby rules to modify them for existing non-conforming members are given in Part 3.…”

Section: Probability Distribution Of Capacitymentioning

confidence: 99%

See 1 more Smart Citation

Reliability‐based partial factors for seismic design and assessment consistent with second‐generation Eurocode 8

Franchin

Noto

2023

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

Second‐generation Eurocode 8 introduces displacement‐based design alongside the traditional force‐based one with reduced equivalent forces; it provides resistance models needed to apply the approach to reinforced concrete, steel and composite frame or wall‐frame structures: chord rotation for members, and shear strength for members and joints; finally, it declares a target reliability level for near collapse. This paper discusses the formulation of partial factors to achieve a target reliability when using the displacement‐based approach. The factors are derived following a traditional, time‐invariant way of performing code‐calibration for other non‐seismic design situations, starting from the probability distributions for the seismic action effect and the resistance. It is shown that the problem can be simplified to one with two Lognormal variables, a uniform reliability can be achieved over the calibration space when both a load‐side and a resistance‐side factor are used, and constant sensitivity coefficients can be used, with values different from the original König and Hosser ones and reflecting the larger weight of the action‐related uncertainty in the seismic case. The problem with this otherwise good result is that a partial factor on the load side must be used and, further, that its value is site dependent. This approach is not in line with current European practice, thus a corrected site‐independent resistance‐side partial factor is proposed, which is compatible with the framework of Eurocode 8. As a further advantage, the proposed format coincides with that proposed in the second‐generation EN1990/EN1992 for the assessment of existing structures under non‐seismic design situations.

show abstract

Section: Reliability Analysissupporting

confidence: 71%

Section: Probability Distribution Of Capacitymentioning

confidence: 99%

Reliability‐based partial factors for seismic design and assessment consistent with second‐generation Eurocode 8

Franchin

Noto

2023

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

show abstract

“…Models at L‐o‐A II are more rational, more robust and objective and of wider applicability. The one presented in this paper is consistent with the fib Model Codes10‐12; a different version, consistent with the second‐generation Eurocode 2 3, has also been proposed 19. Despite their simplicity, L‐o‐A II models for joints do not lend themselves to “back‐of‐the‐envelope” calculation, as the inclination of the compression field that maximizes the shear strength and gives optimum agreement with the experimental data is sought by sweeping practically the full range of possible values, and, as a matter of fact, in an iterative way.…”

Section: Discussionsupporting

confidence: 59%

A levels‐of‐approximation approach to seismic design or assessment of beam‐column joints in shear

Fardis

2020

Structural Concrete

Self Cite

View full text Add to dashboard Cite

Models are proposed for the shear strength of joints, for seismic design or assessment. At first Level‐of‐Approximation, the joint reinforcement and the column axial force are lumped in a single central Tie in the corresponding direction, whose ends are connected through concrete Struts to the two compressed corners of the joint. Concrete strength and Strut widths are independent of strains. At the second Level‐of‐Approximation, any reinforcement is smeared in the volume of the joint and compressive stresses are taken as uniform in a continuous compression field. Concrete strength is taken to decrease with load cycling and increasing transverse tensile strain. As this approach gives zero strength for unreinforced joints without column axial load, a minimum shear strength is added to that from the compression field model. Its magnitude and the reduction in the strength of the compression field with load cycling, as well as the Strut widths for the first Level‐of Approximation, are calibrated using a database of 277 interior and 389 exterior joints tested to shear failure.

show abstract

“…Beam-column joints are the most critical locations of concrete structures whose failure can lead to the collapse of the entire structural system. This beam-column performance and its crucial role in overall structural safety (particularly under lateral seismic loads) is discussed in detail in [14,15]. Damage propagation in a framed system entails significant uncertainties-due to, e.g., the seismic excitation but also the distribution of strength and stiffness in beams and columns-and, therefore, robustness criteria need to be applied by assigning adequate capacity in selected elements of the structure [16].…”

Section: Introduction 1motivation Fundamental Principles and Backgrou...mentioning

confidence: 99%

Minimally Invasive Retrofitting of RC Joints with Externally Applied SMA Plate—Adaptive Design Optimisation through Probabilistic Damage Simulation

2023

View full text Add to dashboard Cite

Beam–column joints are the critical section of many reinforced concrete (RC) structure types in which any failure could lead to the collapse of the entire structure. This paper attempts to employ a superelastic shape memory alloy plate as an innovative and adaptive external strengthening element to rehabilitate existing concrete beam–column joints and enhance the structure’s performance. An experimentally investigated beam–column joint is used as the case study, and it is investigated numerically to validate the effects of an innovative strengthening technique based on shape memory alloys. The results show that the proposed technique could increase the joint’s stiffness and reduce the risk of overall failure. A particular innovation in the proposed method is associated with the novel material itself but also with the fact that the increased potential costs of using special alloys are counteracted by its potential to produce these elements in an optimised industrially produced fastened plate. This fits-all construction product further allows a rapid and minimally invasive strengthening technique. Moreover, to achieve this, the plate is adaptively designed against random critical load combinations through probabilistic damage prediction.

show abstract

Shear strength model for RC joints, consistent with the shear design rules for prismatic members in the second-generation Eurocodes

Cited by 12 publications

References 6 publications

Reliability‐based partial factors for seismic design and assessment consistent with second‐generation Eurocode 8

Reliability‐based partial factors for seismic design and assessment consistent with second‐generation Eurocode 8

A levels‐of‐approximation approach to seismic design or assessment of beam‐column joints in shear

Minimally Invasive Retrofitting of RC Joints with Externally Applied SMA Plate—Adaptive Design Optimisation through Probabilistic Damage Simulation

Contact Info

Product

Resources

About