775 documents found, page 1 of 78
An interpretable machine learning-based model for shear resistance prediction o...
Mohammadi, Amir Hossein; Barros, Joaquim A. O.; Sena-Cruz, JoséExisting analytical models for predicting the shear resistance of RC beams strengthened with externally bonded CFRP reinforcements exhibit deficient performance due to their inability to accurately capture the complex resisting mechanisms. Combined with significant statistical uncertainties in shear failure, driven by its brittle nature, this further undermines the reliability of these models. To address these ...
Blind competition on the numerical simulation of slabs reinforced with conventi...
Barros, Joaquim A. O.; Sanz, Beatriz; Filho, Marcílio; Kabele, Petr; Yu, Rena C.; Meschke, Günther; Planas, Jaime; Cunha, Vitor; Neu, Gerrit E.This paper describes the 3rd Blind Simulation Competition (BSC) organized by the fib WP 2.4.1 which aims to assess the predictive performance of models based on the finite element method (FEM) for analysis and design of fiber reinforced concrete (FRC) structures submitted to loading and support conditions that promote punching failure mode. Fiber reinforcement is used in an attempt to eliminate conventional pun...
Effect of inertia and test approach on the high-strain-rate tensile behavior of...
Bakhshi, Mohammad; Valente, Isabel B.; Ramezansefat, Honeyeh; Barros, Joaquim A. O.High strain rate loadings lead to fundamental modifications in the tensile stress-strain response of steel fiber-reinforced concrete (SFRC). These modifications include higher tensile strength and corresponding strain and fracture energy. This paper investigates the effect of strain rate on the tensile behavior of SFRC, covering ranges from quasi-static (10− 6 to 10− 1 s− 1) to impact (10–50 s− 1). For this pur...
Passive confinement scenarios for strengthening fire-damaged concrete columns: ...
Shayanfar, Javad; Pereira, João P. C.; Barros, Joaquim A. O.The rehabilitation of fire-damaged concrete structures often presents a challenge, leading to costly demolition and reconstruction. This study explores the potential of fiber-reinforced polymer (FRP) passive confinement systems, specifically full, partial, and hybrid configurations, as effective solutions for restoring the compressive strength of heat-damaged concrete columns. Experimental axial compression tes...
Development of sustainable and innovative manhole covers in fibre-reinforced co...
Barros, Joaquim A. O.; Soltanzadeh, Fatemeh; Sousa, Christoph de; Vera, Mónica O.In several countries, manhole covers made of steel are being stolen, with significant economic losses for private and public entities, and even causing accidents. In this work, a new manhole cover is developed using fibre-reinforced cementitious (FRC) materials and glass fibre-reinforced polymer (GFRP) gratings. Since the GFRP gratings are immune to corrosion, and FRC is a relatively low-cost material, manhole ...
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...
Optimizing coastal protection: Nature-based engineering for longitudinal drift ...
Vieira, Bárbara Filipa Vasquez; Pinho, José L. S.; Barros, Joaquim A. O.; Carmo, José Antunes doTraditional hard engineering solutions have shown weaknesses in mitigating erosion processes in vulnerable coastal areas, contributing in some cases to their aggravation, which makes it necessary to study innovative nature-based engineering solutions. This research deals with an in-depth analysis of hydro-morphodynamic modelling results for optimizing the geometry of maritime structures under longitudinal drift...
Multi-objective optimization of unbiased model for externally bonded CFRP syste...
Mohammadi, Amir Hossein; Barros, Joaquim A. O.; Sena-Cruz, JoséPredicting the shear resistance of reinforced concrete (RC) beams strengthened with externally bonded reinforcement (EBR) using carbon fiber-reinforced polymer (CFRP) materials poses a significant challenge due to the complex nonlinear relationship with beam features and the inherent randomness in shear failure events, driven by their brittle nature. This paper proposes a model employing a multi-objective optim...
A comprehensive approach for designing low carbon wood bio-concretes
Gloria, M’hamed Y. R.; Caldas, Lucas R.; Barros, Joaquim A. O.; Toledo Filho, Romildo D.This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed by using the traditional design rules used for conventional mor...
Numerical assessment of the effect of CFRP anchorages on the flexural and shear...
Ayyobi, Pedram; Barros, Joaquim A. O.; Dias, Salvador J. E.This study investigates the effectiveness of a hybrid solution that combines carbon fiber-reinforced polymer (CFRP) systems for the flexural and shear strengthening of T-cross section reinforced concrete (RC) beams. The hybrid solution consists of near-surface mounted CFRP laminates for flexural enhancement and externally bonded U-shaped CFRP strips for shear strengthening. Moreover, an innovative CFRP anchorag...