Juan Francisco Carbonell Márquez | Universidad de Córdoba (original) (raw)

Papers by Juan Francisco Carbonell Márquez

The assessment of the residual flexure capacity of existing reinforced concrete structures affect... more The assessment of the residual flexure capacity of existing reinforced concrete structures affected by corrosion is a key point for reparation and rehabilitation works. A procedure for the evaluation of the residual flexure capacity of corroded RC members due to steel-to-concrete bond deterioration and steel cross-section reduction taking into account the original reinforcement layout is presented. The approach is based on different models provided in the literature to account for the main corrosión effects.. Some examples are provided

Engineering Structures, 2021

This technical note introduces a new graphical representation which allows the visualization of t... more This technical note introduces a new graphical representation which allows the visualization of the energy balance of a structure subjected to dynamic loading using hysteretic curves. Hysteretic curves were originally created to describe the behavior of magnetic materials. They were later introduced into structural engineering to describe the behavior of structures subjected mainly to seismic loading. In their current form, the hysteretic curves used in structural dynamics do not provide the information required to analyze the energy history of their behavior, this is due to the fact that velocity, a relevant variable in the description of the history of displacements, is not present. In this technical note, the authors present a new concept: the energy-balanced hysteretic curve, consisting of a graph that contains all the information needed to analyze the history of the displacements and the energy balance during the motion of the structure. Detailed examples show the benefits of this new representation.

Report TEP 190 1-2019The numeric computation procedure for the solution of the equation of motion... more Report TEP 190 1-2019The numeric computation procedure for the solution of the equation of motion of a single-degree-of-freedom (SDOF) system subjected to any type of ground acceleration is exhaustively presented. The followed numeric approach is the Linear Acceleration Method, i.e. Newmark’s Method with γ=1/2 and β=1/6. The approach allows considering any time of multilinear elasto-plastic behavior. It also allows computing the Complete Hysteretic Curve of the SDOF system

Artículo publicado en Applied Mathematics LettersThe magnification factor for the steady-state re... more Artículo publicado en Applied Mathematics LettersThe magnification factor for the steady-state response of a SDOF system under harmonic loading is described in many structural dynamics textbooks; the well known analytical solution is easily obtained from the solution to the damped equation of motion for harmonic loading. The complete and steady state solutions can differ significantly. An analytical expression for the maximum response to the complete solution (steady state plus transient) remains elusive; however, a simple analytical expression is identified herein for the undamped case. Differences in the magnification factors obtained for both solutions are discussed.TEP-19

Para el diseño de un elemento estructural tipo viga-columna se suelen seleccionar secciones doble... more Para el diseño de un elemento estructural tipo viga-columna se suelen seleccionar secciones doblemente simétricas, generalemente secciones laminadas tipo H o I. Sin embargo, ésta es sólo una de las muchas soluciones posibles y, por lo general, no será la sección óptima. Hernández-Montes et al. 2004, y Hernández-Montes et al. 2005, proponen los diagramas RSD (Reinforcement Sizing Diagrams) como un método para obtener la solución óptima para el armado longitudinal de una sección de hormigón sometida a flexión uniaxial y a compresión. Esta metodología ha sido extendida para secciones de acero compactas según el Eurocódigo 3 (EC3) por Gil-Martín et al. 2008, y esta comunicación procederá de manera similar para buscar soluciones no compactas, esto es, soluciones en clases 3 ó 4 según EC3, considerando todos los aspectos relacionados con la aparición de inestabilidades locales. Además, se introducirán las consideraciones especiales para tener en cuenta las inestabilidades globales relacio...

Detailed application of the Linear Acceleration Method for the response of an elasto-plastic SDOF... more Detailed application of the Linear Acceleration Method for the response of an elasto-plastic SDOF system

The process of form finding of shell structures was always a challenge for architects and enginee... more The process of form finding of shell structures was always a challenge for architects and engineers, and an issue of effective collaboration. Tools which allow finding an equilibrium shape of structure change a lot as time goes by. Modified Force density method together with topological mapping is applied for form finding of compressed structures. GAUDI software is a new form‐finding tool based on constant values of the force:length ratios that give endless opportunities for creativity for architects and engineers. It allows finding an equilibrium shape of structure initially desired by an artist by iteratively changing input parameters. With this tool, forces follow any well conceived form of structure. This new conception changes the traditional notion of “form follows forces” to “forces follow a well conceived form”

The effective tension area of concrete is a well known parameter in structural concrete. It is in... more The effective tension area of concrete is a well known parameter in structural concrete. It is involved in several phenomena that affect the design of structural concrete elements, such as cracking, shear deformation or flexural deformation. In this work, the authors put forward a necessary change in the definition of the effective tension area of concrete provided by some groups of Standards.

The Force Density Method has been traditionally employed to seek the equilibrium shape of tension... more The Force Density Method has been traditionally employed to seek the equilibrium shape of tension structures. Recently, the use of a process based on topology has been introduced to provide a first network in which the Force Density Method can be applied. Compression-only structures such as vaults and domes can also be modelled by means of the former approach if this is modified to get a design process similar to the Gaudí’s one based on hanging models. The conjunction of Topological Mapping and the Forced Density Method is first explained in the form-finding process of tension structures and, later on, the modifications to that approach are introduced so that an iterative procedure is obtained to get equilibrium shapes of compression-only structures. The versatility of this novel approach is presented by means of the analysis of some representative examples

Third International Conference on Mechanical Models in Structural Engineering (CMMoST2015). Schoo... more Third International Conference on Mechanical Models in Structural Engineering (CMMoST2015). School of Architecture, Seville, Spain, 24th to 26th June 2015.

Construction and Building Materials, 2016

Construction and Building Materials, 2020

The repair and rehabilitation of Reinforced Concrete (RC) structures affected by the corrosion of... more The repair and rehabilitation of Reinforced Concrete (RC) structures affected by the corrosion of their reinforcement is a complex task. The estimation of the residual structural capacity of corroded RC structures is becoming a crucial factor in the decision-making process of repair or demolition. Many researchers have studied the effects of reinforcement corrosion on the load capacity of RC beams (Bernoulli or B-Regions) but little attention has been paid to disturbed or D-Regions. This piece of work presents a procedure for the assessment of the residual structural capacity of D-Regions in RC members. The bond deterioration between steel and concrete, the reduction of the cross-sectional area of reinforcement, the deterioration of the concrete area of the crosssection and the softening of concrete has been taken into consideration. The accuracy of the method has been tested with experimental results which exist in relevant literature.

Construction and Building Materials, 2018

h i g h l i g h t s The introduction of polymers in concrete is gaining more traction in civil en... more h i g h l i g h t s The introduction of polymers in concrete is gaining more traction in civil engineering. Concrete with ground tyre rubber presents a flatter post-peak branch in the stress-strain. Concrete mixtures with epoxy without hardener has shown the highest durability.

Construction and Building Materials, 2016

Abstract The estimation of the residual capacity of concrete structures after the commencement of... more Abstract The estimation of the residual capacity of concrete structures after the commencement of corrosion of steel reinforcement is becoming a goal for repair and rehabilitation work. This paper presents a procedure for the assessment of the residual structural capacity of corrosion-affected RC members due to bond deterioration and reduction of the cross-section of the reinforcing steel bars, taking the reinforcement layout and details into account. Many researchers have studied the effect of corrosion on the flexural behavior of reinforced concrete beams but this piece of work introduces the way in which the corrosion levels can be accounted for from a structural point of view, in order to quantify the loss of capacity of B regions in RC members. The accuracy of the proposed method has been tested with experimental results of naturally corroded RC beams that exist in the relevant literature.

Archives of Civil and Mechanical Engineering, 2017

Reinforced concrete piles employed in earth retaining systems are typically designed with symmetr... more Reinforced concrete piles employed in earth retaining systems are typically designed with symmetric reinforcement. The non-symmetric RC wall piles have recently been introduced by the authors, obtaining savings of up to 50% in weight in longitudinal reinforcing steel compared with the traditional solutions, leading to significant financial savings while also reducing associated environmental impacts. The structural behavior of this new RC member under long-term loading is studied, comparing it with its symmetrical counterpart. An experimental campaign has been carried out. Full scale specimens with circular cross sections symmetrically and asymmetrically reinforced were tested. Results have shown that asymmetrically RC pile developed a slightly higher deflection than its symmetrical counterpart. A new expression for the effective area of concrete in tension applicable to non-symmetrical piles is introduced. Moreover, a new stress-strain law for cracked concrete that accounts the tension stiffening effect for longterm loading is proposed. Finally, for non-symmetrical RC wall piles, the evolution of the parameter that takes into account the duration of loading in deformations is presented. Although more evidence is needed, it is shown that tension stiffening effect contribution could be overestimated by Eurocode 2 in the case of non-symmetrically or underestimated in case of symmetrically RC piles.

Engineering Structures, 2017

Domes and vaults, with or without inner ribs, can be modelled as pin-jointed networks with all th... more Domes and vaults, with or without inner ribs, can be modelled as pin-jointed networks with all their members in compression. The Force Density Method is one of the most widely used form-finding methods for the computation of the equilibrium shape of pin-jointed networks. Mapping in topology, in contrast with other mapping methods, does not need an initial estimate of the equilibrium position as part of the solution process. Patterns of force:length ratios are proposed in the present work with the aim of designing compression structures with inner ribs. These patterns are based on the assignment of a higher value of force:length ratio to certain groups of members (rib lines) in order to obtain ribs in the final shape. In this paper a complete procedure for the design of vaults with inner ribs is proposed. Finally two examples inspired by two vaults of the Cathedral of Granada (Spain) are shown using the proposed procedure.

Archive of Applied Mechanics, 2016

Force density method together with topological mapping has been employed to perform the form-find... more Force density method together with topological mapping has been employed to perform the form-finding process of tension structures. Compression-only structures such as domes and vaults can be modelled if the former approach is modified. This modification consists of iteratively introducing the self-weight of the structure to be modelled until the equilibrium configuration is found. This method is similar to the hanging chain models employed by Antonio Gaudí when designing his structures. The approach allows rapidly changing the input parameters in order to get different equilibrium configurations.

Engineering Structures, 2021

Construction and Building Materials, 2016

Construction and Building Materials, 2020

Construction and Building Materials, 2018

Construction and Building Materials, 2016

Archives of Civil and Mechanical Engineering, 2017

Engineering Structures, 2017

Archive of Applied Mechanics, 2016

A new position for a PhD student is now opened at the Department of Engineering of Universidad Lo... more A new position for a PhD student is now opened at the Department of Engineering of Universidad Loyola Andalucía under the supervision of Francisco Montero Chacón and Juan F. Carbonell Márquez. In this project, we propose the analysis of energy storage systems (ESS) at different scales of observation, namely the material level in order to understand the physical phenomena involved in the storage mechanism (e.g. diffusion), the component level in which materials can be treated as homogeneous media, and finally the system level on which life-cycle tests can be carried out in order to assess their performance. This approach requires the combination of different tools (e.g. discrete models) or even mesoscale modeling tools that filling the gap between the discrete and continuum scales (e.g. quasi-continuum methods at finite temperature), in order to understand the aforementioned physical processes. From the continuum scale perspective, we aim at developing advanced coupled thermal-electro-chemo-mechanical finite element models on which perform life-cycle tests, while interacting with lower-scale models via multiscale techniques. This approach is regardless of the type of the EES subjected to study (e.g., Li-ion batteries, phase-change materials, thermochemical storage, or sensible storage devices).

Most of the literature concerning the distributed estimation of systems assume that the network o... more Most of the literature concerning the distributed estimation of systems assume that the network of agents (sensors with some computational capacity) have a common objective, that is, the proper estimate of the current state. However, it is possible to find applications in which the
collaboration between agents could be more profitable for some of the agents than for others. In these cases, negotiation schemes must be implemented, since local cost functions could be against the global ones. This thesis will investigate the application of game theory and the paradigm of competitive optimization to the problem of distributed estimation.