82 documents found, page 1 of 9
Experimental and analytical study of the high-strain rate flexural behavior of ...
Bakhshi, Mohammad; Valente, Isabel B.; Ramezansefat, Honeyeh; Barros, Joaquim A. O.; Pereira, E. N. B.; Peixinho, NunoSteel fiber-reinforced concrete (SFRC) with hooked-end steel fibers was created for use in urban furniture to protect against blast and impact loads. Due to the variety of impact loads that these structures may experience, it is necessary to assess the impact of high strain rates on the flexural behavior of SFRC. This study involved testing SFRC beams with 1% volume content of hooked-end fibers, which were 30 m...
Numerical and experimental characterisation of polylactic acid (PLA) processed ...
Salgueiro, Mariana P.; Pereira, Fábio A. M.; Faria, C.L.; Pereira, E. N. B.; Almeida, João Alberto Pinheiro Pereira; Campos, Teresa D.; Fakher, ChaariIn additive manufacturing (AM), one of the most popular procedures is material extrusion (MEX). The materials and manufacturing parameters used in this process have a significant impact on a printed product’s quality. The purpose of this work is to investigate the effects of infill percentage and filament orientation on the mechanical properties of printed structures. For this reason, the characterisation of po...
Toughness of natural hydraulic lime fibre-reinforced mortars for masonry streng...
Almeida, João Alberto Pinheiro Pereira; Barros, Joaquim A. O.; Pereira, E. N. B.Masonry structures are susceptible to damage and collapse due to seismic actions, a problem in many urban areas. To address this issue, researchers are studying the use of fibre-reinforced mortars as overlay strengthening systems. This study assessed the use of synthetic polyacrylonitrile (PAN) fibres as reinforcement of natural hydraulic lime mortar, focusing on their influence on fresh behaviour and mechanica...
Experimental and analytical study of the high-strain-rate compressive behavior ...
Bakhshi, Mohammad; Valente, Isabel B.; Ramezansefat, Honeyeh; Barros, Joaquim A. O.; Pereira, E. N. B.; Peixinho, NunoThe compressive behavior of steel-fiber-reinforced-concrete (SFRC) is dependent on the loading rate. This research investigates, experimentally and analytically, the effect of loading rate on the compressive behavior of SFRC designed to be used in prefabricated urban protective furniture. For this purpose, cylinder SFRC specimens were subjected to modified instrumented-drop-weightimpact tests at four dropping h...
Landslide analysis combining laser scanning and photogrammetry
Pinto, Pedro; Barros, Juliana; Pinheiro, Marisa Mota; Tomás, Roberto; Miranda, Tiago F. S.; Pereira, E. N. B.After a sequence of weeks of heavy raining, a catastrophic mass movement occurred in the parish of Palmeira de Faro, Esposende (N Portugal) on November 23, 2022. The collapsed slope presented a maximum height of about 21 m and a length of 45 m. In order to document and analyse this case from the geotechnical perspective, a general survey was devised including the use of aerial photography, laser scanning and co...
Knitted textile KTPs for instrumented underwater building systems
Monteiro, Filipa Maria Barbosa Faria; Pereira, E. N. B.; Almeida, João Alberto Pinheiro Pereira; Cruz, Fábio Quintas; Barajas, Diddyer Alexander Prada[Excerpt] The main scope of this study was to assess the potential of knitted textiles for underwater instrumented underwater building systems, using textile knitted preforms (multi-shape; multimaterial; etc…), using natural fibres (Hemp, Linen and Cotton).
Sustainability assessment of half-sandwich panels based on alkali-activated cer...
Vaca, Norma Yolanda Gaibor; Mateus, Ricardo; Leitão, Dinis; Cristelo, Nuno; Miranda, Tiago F. S.; Pereira, E. N. B.; Cunha, Vitor M. C. F.This study assessed the sustainability of two partition walls and intended to contribute to the Circular Economy in the construction sector. A life cycle approach and a multi-criteria decision support method were applied to know the environmental, functional, and economic performances of the production process of half-sandwich panels based on alkali-activated ceramic/slag waste cement, choosing as system bounda...
Experimental assessment of the thermo-mechanical bond behavior of NSM CFRP with...
Mohammadifirouz, Reza; Pereira, E. N. B.; Barros, Joaquim A. O.Cement-based materials, which are incombustible and show low thermal diffusivity, show great potential as a valid alternative to polymeric matrices for bonding near surface mounted (NSM) carbon fiber reinforced polymer (CFRP) systems for the strengthening of reinforced concrete (RC) structures. The performance of these materials in different loading conditions, including high temperature exposure, still needs t...
Numerical analysis of the flow field and cross section design implications in a...
Maslov, Dmytro; Pereira, E. N. B.; Duarte, Duarte; Miranda, Tiago F. S.; Ferreira, Vasco; Tieppo, Marcos; Cruz, Fábio; Johnson, JessicaNowadays, multifunctional artificial reefs are integrated in coastal areas all around the world. The design of such structures is currently complex and subjective. In this context, it is essential to improve overall design approaches to more effectively relate artificial reef geometry, function and optimal performance to specific deployment sites. Part of the solution to this challenge may lie in the use of in ...
Feasibility of mechanical post-tensioning of annealed glass beams by activating...
Rocha, Jorge; Pereira, E. N. B.; Sena-Cruz, JoséThe structural concept of post-tensioned glass systems has been investigated to minimize the unpredictable response of structural glass in tension. The Fe-SMAs have been successfully explored for strengthening existing structures due to their advantages in comparison with the conventional reinforcement materials. In particular, the recently developed Fe-17Mn-5Si-10Cr-4Ni-1VC (mass-%) alloy seems sustainable and...