DEN: Thesis SL-DEN-16-0083 - instn
Transcription
DEN: Thesis SL-DEN-16-0083 - instn
DEN: Thesis SL-DEN-16-0083 RESEARCH FIELD Mechanics, energetics, process engineering / Engineering science TITLE STRUCTURAL ASSESSMENT OF EXISTING REINFORCED CONCRETE STRUCTURES: COUPLING BETWEEN CORROSION AND EARTHQUAKE LOADING ABSTRACT The corrosion phenomenon can be considered as one of the major pathologies affecting the reinforcing bars put in reinforced concrete structure to handle tension loads and consequently, contributing to the loss of performance of existing buildings. This phenomenon is due to the diffusion process in concrete of chemical species, such as chlorides or dioxide carbonyl. As soon as their content has reached a specific threshold, an electro-chemical reaction takes place and rust products are created. The chemical nature of rust products depends mainly on the nature of aggressive species responsible for their creation. More precisely, the corrosion phenomenon leads to three major mechanical effects: (i) the reduction of the steel cross-section leading to a reduction of the local (at least) ductility; (ii) the initiation of cracking from the steel reinforcing bars to the concrete cover due to the expansive nature of the rust products and (iii) the modification of the bond properties at the steel/concrete interface according to the corrosion level. For the decades, noticeable works have been carried out with the aim to better understand and predict the mechanical behavior of corroded reinforced concrete structures subjected to monotonic loading. In particular, these works have led to the creation of data allowing quantifying the loss of the bearing capacity of existing structures. However, only a few studies are available regarding the case of cyclic loading and none (according to our knowledge) regarding the case of low velocity dynamic loading (such as earthquake loading). Within this framework, this work aims at bringing some new pieces of knowledge to understand the effect of the corrosion phenomenon on the seismic response of reinforced concrete structures. To reach this aim, the testing devices available on the TAMARIS operated by CEA experimental facility will be used. The objectives of this work are (i) to define and follow up an experimental campaign including seismic tests to exhibit the effect of the corrosion phenomenon on the seismic response of reinforced concrete structures, to analyze the experimental data to make the current knowledge move forward and (iii) to formulate a simplified numerical model aiming at describing the main mechanical consequences from the corrosion phenomenon on the seismic behavior of reinforced concrete structures. LOCATION Département de Modélisation des Systèmes et Structures Service d'Etudes Mécaniques et Thermiques Laboratoire d'Etudes de Mécanique Sismique Place: Saclay Start date of the thesis: 01/10/2016 CONTACT PERSON Benjamin RICHARD CEA DEN/DM2S/SEMT/EMSI Commissariat à l'énergie atomique et aux énergies alternatives Institut national des sciences et techniques nucléaires wwwinstn.cea.fr 1 CEA Saclay Batiment 603 - Pièce 8 - Point 112 91191 Gif-sur_Yvette CEDEX Phone number: +33 1 69 08 76 74 Email: [email protected] UNIVERSITY / GRADUATE SCHOOL ENS Cachan Annulé FIND OUT MORE https://www.linkedin.com/pub/benjamin-richard/16/75b/355 http://www-tamaris.cea.fr/ THESIS SUPERVISOR Frédéric RAGUENEAU ENS Cachan LMT Cachan / Paris VI L.M.T. Cachan 61 Avenue du Président Wilson 94235 CACHAN Cedex Commissariat à l'énergie atomique et aux énergies alternatives Institut national des sciences et techniques nucléaires wwwinstn.cea.fr Powered by TCPDF (www.tcpdf.org) 2