Search results for " push-out tests"

Travi reticolari miste- Problemi locali nella trasmissione degli sforzi

2009

Experimental test results on the local behavior of the typical Italian typology of hybrid steel-to-concrete beam are presented and discussed in order to provide insight on transfer mechanism between different components of the beam. Preliminarily, in order to investigate on the bearing capacity of the welding and on the local instability problems that can arise in the trusses before concrete casting, tensile tests on specimens reproducing different types of welded joints, and push-out tests on bare specimen have been performed. Then, the transfer mechanism between steel trusses and concrete is investigated by means of push-out tests carried out also in displacement controlled mode. Results …

FEM analysis of push-out test response of Hybrid Steel Trussed Concrete Beams (HSTCBs)

2015

Abstract Aiming to investigate the steel truss–concrete stress transfer mechanism in Hybrid Steel Trussed–Concrete Beams (HSTCBs), a three-dimensional (3D) nonlinear Finite Element (FE) model is developed. The constitutive relationship of the steel composing the plates and the rebars is modeled by means of a quadri-linear law, while the concrete behavior is defined by means of a Concrete Damaged Plasticity (CDP) model, suitable for modeling concrete and brittle materials. Two main failure mechanisms are considered, namely the tensile cracking and the compressive crushing. In order to accurately grasp the complicate dowel and bond phenomena arising at the steel–concrete interface, a 3D solid…

Assessment of push-out test response of hybrid steel trussed-concrete beams by FE model

2013

Aiming to investigate the truss-concrete stress transfer mechanism in Hybrid Steel Trussed-Concrete Beams (HSTCBs), a three-dimensional nonlinear FE model is developed. The constitutive laws of the steel composing the plates and the bars is modeled by means of a quadri-linear law, while the concrete behavior is defined by means of a Concrete Damaged Plasticity (CDP) model, suitable for modeling concrete and brittle materials. The CDP model uses the concept of isotropic damaged elasticity in combination with isotropic tensile and compressive plasticity and is able to properly account for the concrete confinement effect. Two main failure mechanisms are considered, namely the tensile cracking …

Analytical prediction of the shear connection capacity in composite steel–concrete trussed beams

2016

Steel–concrete trussed composite beams are a particular types of composite girders constituted by a steel truss embedded in a concrete core. The truss is typically composed by a steel plate or a precast concrete slab working as bottom chord while coupled rebars are generally used to form the upper chord. Moreover, a system of ribbed or smooth steel rebars welded to the plate and forming the diagonals of the truss, works as web reinforcement. In the present study, the attention is focused on the evaluation of the shear resistance of the connection between bottom steel plate (the bottom chord) and concrete core through the diagonal bars of the truss developing a mechanical model able to accou…

Experimental analysis, numerical and analytical modeling of shear strength mechanisms in Hybrid Steel Trussed Concrete Beams

2014

Testing and Modeling of Hybrid Steel-Trussed Concrete Beams in Shear

2014

Evaluation of the shear connection strength of precast hybrid steel-trussed-concrete composite beams

2015

In last decades, significant efforts have been carried out by the scientific community to evaluate the main technical issues of Hybrid Steel-Trussed-Concrete beams, investigating both the first opera-tive phase, i.e. before the concrete casting, when only the bare truss works, and, the second phase, i.e. after the concrete curing, when the beam works as a composite element. In the present study, the attention is focused on the evaluation of the shear strength of the connection between the bottom plate of the steel truss and the concrete core proposing a mechanical model able to predict its ulti-mate resistance. The proposed mechanical formulation is mainly based on the extension of existing…

Modeling of the Shear Connection Capacity of Hybrid Steel Trussed Composite Beams

2019

Hybrid Steel Trussed Composite Beams represent a technical solution in use in numerous countries since many years. They are able to join the advantages of prefabrication with those of cast in place structures: they are easy to manufacture, fast to realize, monolithic and with no need of formwork. The behavior of these beams has been recently topic of discussion in the scientific community because the knowledge both related to the reinforced concrete structures and that of composite constructions cannot be straightforwardly extended to this typology, which is intermediate between one and another technology. This paper provides a contribution towards a better understanding of the mechanism of…

Stress transfer mechanism investigation in hybrid steel trussed-concrete beams by push-out tests

2014

Abstract Results of push-out tests carried out on Hybrid Steel Trussed–Concrete Beams (HSTCBs) before and after the concrete casting are presented and interpreted. Firstly, in order to check the ability of weldings before casting, tensile tests were performed on specimens reproducing different types of welded joints. Simplified design formulae were used to predict their ultimate strength. Secondly, results obtained by push-out tests on specimen representative of the beam before and after the concrete casting are presented and discussed. Finally, simplified analytical models proposed by the current European building code were adapted to the specific typology to roughly predict the ultimate s…