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Gravity loads can affect a reinforced concrete structure’s response to seismic actions, however, traditional procedures for testing the beam behaviour do not take this effect into consideration. An experimental campaign was carried out in order to assess the influence of the gravity load on RC beam connection to the column subjected to cyclic loading. The experiments included the imposition of a conventional quasi-static test protocol based on the imposition of a reverse cyclic displacement history and of an alternative cyclic test procedure starting from the gravity load effects. The test results are presented, compared and analysed in this paper. The imposition of a cyclic test procedure that included the gravity loads effects on the RC beam ends reproduces the demands on the beams’ critical zones more realistically than the traditional procedure. The consideration of the vertical load effects in the test procedure led to an accumulation of negative (hogging) deformation. This phenomenon is sustained with the behaviour of a portal frame system under cyclic loads subject to a significant level of the vertical load, leading to the formation of unidirectional plastic hinges. In addition, the hysteretic behaviour of the RC beam ends tested was simulated numerically using the nonlinear structural analysis software – OpenSees. The beam–column model simulates the global element behaviour very well, as there is a reasonable approximation to the hysteretic loops obtained experimentally.

Submitted by António Santos Silva (ssilva@lnec.pt) on 2013-08-21T13:15:36Z No. of bitstreams: 1 Pontes et al_abstract.pdf: 6674 bytes, checksum: b335e9935a490dec4224ef46eb02759f (MD5) Approved for entry into archive by arlindo@lnec.pt(arlindo@lnec.pt) on 2013-08-21T14:59:05Z (GMT) No. of bitstreams: 1 Pontes et al_abstract.pdf: 6674 bytes, checksum: b335e9935a490dec4224ef46eb02759f (MD5) Made available in DSpace on 2013-08-21T14:59:05Z (GMT). No. of bitstreams: 1 Pontes et al_abstract.pdf: 6674 bytes, checksum: b335e9935a490dec4224ef46eb02759f (MD5) Previous issue date: 2013 Made available in DSpace on 2014-10-20T16:31:37Z (GMT). No. of bitstreams: 2 license.txt: 1838 bytes, checksum: 86a2232ba0f6899d94164cce0c845931 (MD5) Pontes et al_abstract.pdf: 6674 bytes, checksum: b335e9935a490dec4224ef46eb02759f (MD5) Previous issue date: 2013 Made available in DSpace on 2017-04-13T11:11:14Z (GMT). No. of bitstreams: 2 Pontes et al_abstract.pdf: 6674 bytes, checksum: b335e9935a490dec4224ef46eb02759f (MD5) license.txt: 1838 bytes, checksum: 86a2232ba0f6899d94164cce0c845931 (MD5) Previous issue date: 2013 The authors wish to acknowledge the Fundação para a Ciência e Tecnologia (FCT) for the financial support under project METACAL (PTDC/ECM/100431/2008) and to the enterprises Fradical, Portucel and IMERYS for the supply of pozzolans used in this work. The authors wish also to aknowledge the institutions of LNEC – Laboratório Nacional de Engenharia Civil and FCT–UNL – Faculdade de Ciências e Tecnologia – Universidade Nova de Lisboa for the technical support and facilities admission in order to perform the tests. 6 1 433-438pp Vols. 730-732 DM/NMM Materials Science Forum

The aim of this work is to provide new contributions in order to define more accurately the structural robustness concept, particularly when it is applied to corroded reinforced concrete (RC) structures. To fulfill such task, several robustness indicators are analyzed and discussed with special emphasis given to the structural performance based measures. A new robustness definition and a framework to assess it are then proposed, based on the structural performance lost after damage occurrence. The competence of the proposed methodology is then tested comparing the robustness of two reinforced concrete foot bridges under corrosion. Damage considered is the longitudinal reinforcement corrosion level and load carrying capacity is the structural performance evaluated. In order to analyze corrosion effects, a finite element based two step analysis is adopted. On the first step a cross section analysis is performed to capture phenomenons such as: expansion of the reinforcement due to the corrosion products accumulation; damage and cracking in the reinforcement surrounding concrete; steel-concrete bond strength degradation; and effective reinforcement area reduction. The results obtained are then used to built a 2D structural model, in order to assess the maximum load carrying capacity of the corroded structure. For each foot bridge, robustness is finally assessed using the proposed methodology. Fil: Cavaco, Eduardo. Universidade Nova de Lisboa; Portugal Fil: Casas, Joan R.. Universidad Politecnica de Catalunya; España Fil: Neves, Luis A. C.. Universidade Nova de Lisboa; Portugal Fil: Huespe, Alfredo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico. Centro de Investigación de Métodos Computacionales; Argentina

Building stones, particularly sandstone and granite, are very important in the building elements of Portugal’s historical and cultural heritage. Experimental research, based on uniaxial compressive tests, was carried out on selected representative samples of lithotypes of rocks used in historic built heritage, with a view to evaluating the compressive mechanical behaviour of different building stones. The results showed that porosity plays a central role in the compressive behaviour of granites and sandstones. As porosity can be evaluated in field conditions with non-destructive tests it was decided to derive an analytical model to predict compressive behaviour based on the knowledge of porosity of the building stones. A cubic polynomial function was adopted to describe the pre-peak regime under compression to implement the model. Furthermore, a statistical correlation between mechanical and porosity data had to be defined. Good agreement between experimental and analytical compressive stress–strain diagrams, from which the mechanical properties like compressive strength and modulus of elasticity can be derived, was achieved.

Major similarities between robustness assessment and seismic design exist, and significant information can be brought from seismic design to robustness design. As will be discussed, although some methods and limitations considered in seismic design can improve robustness, the capacity of the structure to sustain limited damage without disproportionate effects is significantly more complex. In fact, seismic design can either improve or reduce the resistance of structures to unforeseeable events, depending on the structural type, triggering event, structural material, among others. Based on a case study, the influence of redundancy and ductility on the seismic behavior and robustness of a long-span timber structure is assessed., COST E 55

Submitted by teresag@lnec.pt (teresag@lnec.pt) on 2011-06-14T14:11:28Z No. of bitstreams: 1 Coatings applied on damp building substrates.doc: 26624 bytes, checksum: b5ed94c2f737316f87526032d4576a0b (MD5) Approved for entry into archive by arlindo@lnec.pt(arlindo@lnec.pt) on 2011-06-14T15:48:59Z (GMT) No. of bitstreams: 1 Coatings applied on damp building substrates.doc: 26624 bytes, checksum: b5ed94c2f737316f87526032d4576a0b (MD5) Made available in DSpace on 2011-06-14T15:48:59Z (GMT). No. of bitstreams: 1 Coatings applied on damp building substrates.doc: 26624 bytes, checksum: b5ed94c2f737316f87526032d4576a0b (MD5) Previous issue date: 2011 Made available in DSpace on 2014-10-20T15:58:50Z (GMT). No. of bitstreams: 3 Coatings applied on damp building substrates.doc.txt: 1582 bytes, checksum: 187b24c24cb363b6644b87f3823d0368 (MD5) license.txt: 1833 bytes, checksum: 3fd8c2fd828ccccd1384765a0c16fc52 (MD5) Coatings applied on damp building substrates.doc: 26624 bytes, checksum: b5ed94c2f737316f87526032d4576a0b (MD5) Previous issue date: 2011 Made available in DSpace on 2017-04-13T08:40:04Z (GMT). No. of bitstreams: 2 Coatings_applied_on_damp_building_substrates.pdf: 74552 bytes, checksum: 5edba26f1683cefe0b8f5caa9a1ca355 (MD5) license.txt: 1833 bytes, checksum: 3fd8c2fd828ccccd1384765a0c16fc52 (MD5) Previous issue date: 2011 9 8 513–525 8 (4) DM/NPC Journal of Coatings Technology and Research