Publications de Hammad El Jisr

Full-Scale Tests to Characterize the Effect of Framing Action and Slab Continuity on the Collapse Capacity of Composite Frames Under Cyclic Loading

This paper presents an experimental study that examined the role of the slab continuity and framing action on the overall hysteretic behavior of a composite-steel moment resisting frame (MRF) up until incipient collapse using advanced instrumentation. The ...

2024

Full Scale Experiments of a Composite Steel Moment Resisting Frame: Behavioral Insights and Implications on Seismic Design

Dimitrios Lignos, Hammad El Jisr

This paper discusses the cyclic performance of a heavily instrumented 2-bay full-scale composite-steel moment resisting frame (CMRF) sub-system from the onset of structural damage up until incipient collapse. The CMRF featured stiffened end plate bolted co ...

EEME2023

Proposed nonlinear macro-model for seismic risk assessment of composite-steel moment resisting frames

Dimitrios Lignos, Hammad El Jisr

This paper proposes a macro-model for simulating the hysteretic behavior of composite-steel beams as part of fully restrained beam-to-column connections in composite-steel moment-resisting frames (MRFs). Comparisons with experimental data suggest that the ...

WILEY2022

The Role of the Composite Floor System and Framing Action in the Seismic Performance of Composite Steel Moment-Resisting Frames

Hammad El Jisr

With the advent of performance-based earthquake engineering (PBEE), the need for reliable prediction of earthquake-induced collapse of structures is essential. Despite the significant progress that has been made towards this goal, there are several hurdles ...

EPFL2022

Hysteretic Behaviour of Shear Stud Connectors in Composite Steel Moment‐Resisting Frames

Dimitrios Lignos, Hammad El Jisr

In steel moment resisting frames (MRFs) with composite floor slabs, seismic loads are transmitted from the slab into the beam through shear studs. Shear strength degradation of the studs due to cyclic loading results into the loss of the load transfer mech ...

2021

Fragility Assessment of Beam-Slab Connections for Informing Earthquake-Induced Repairs in Composite-Steel Moment Resisting Frames

Dimitrios Lignos, Hammad El Jisr

Earthquake loss estimation in composite-steel moment resisting frames (MRFs) necessitates a proper estimation of the level of damage in steel beam-to-slab connections. These usually feature welded headed shear studs to ensure the composite action between t ...

2021

Hysteretic Behavior of Moment-Resisting Frames Considering Slab Restraint and Framing Action

Dimitrios Lignos, Hammad El Jisr, Ahmed Mohamed Ahmed Elkady

This paper examines the influence of framing action and slab continuity on the hysteretic behavior of composite steel moment-resisting frames (MRFs) by means of high-fidelity continuum finite-element (CFE) analyses of two-bay subsystems and typical crucifo ...

2020

Composite steel beam database for seismic design and performance assessment of composite-steel moment-resisting frame systems

Dimitrios Lignos, Hammad El Jisr, Ahmed Mohamed Ahmed Elkady

This paper discusses the development of a publicly available database of composite steel beam-to-column connections under cyclic loading. The database is utilized to develop recommendations for the seismic design and nonlinear performance assessment of ste ...

2019

Composite beam effects and implications to seismic design provisions

Dimitrios Lignos, Hammad El Jisr

Previous studies have investigated the slab effects on the cyclic behavior of composite beams in moment-resisting frames. Of interest in this paper, is the slab contribution to the flexural strength and effective stiffness of the beam. The former influence ...

2018