Banca de QUALIFICAÇÃO: ELAYNE MARQUES SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ELAYNE MARQUES SILVA
DATA : 05/08/2019
HORA: 14:30
LOCAL: Auditório do Prédio 18
TÍTULO:

Experimental Investigation and Probabilistic Assessment of Serviceability Limit State of Cracking of GFRP-Reinforced Concrete Members

PALAVRAS-CHAVES:

Bond-Dependent Coefficient, Concrete, FRP, Crack Width, Serviceability Limit State, Reliability, Probability, Monte Carlo simulation

PÁGINAS: 50
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Civil
SUBÁREA: Construção Civil
ESPECIALIDADE: Materiais e Componentes de Construção
RESUMO:

Many reinforced concrete (RC) structures are subjected to deicing salts or in harsh environments that reduces the alkalinity of concrete, leading to corrosion of steel reinforcement and, consequently, affecting the service life of structures. In this way, Fiber-Reinforced Polymers (FRP), as noncorrosive materials, have emerged as an alternative to steel as internal reinforcement in concrete structures to mitigate the problem of corrosion. Although the FRP shows a promising prospect for use as reinforcement, the mechanical properties of the bars – low modulus of elasticity and high tensile strength – lead to change in the design paradigm for FRP-reinforced concrete (FRP-RC) structures. While RC structures are designed based on ultimate limit state of strength and then checked for serviceability limit state requirements, the design of FRP-RC members usually will be control almost exclusively by serviceability criteria (deflection and cracking). Many studies have been conducted regarding the deflection of FRP-RC beams, but the amount of studies with respect to cracking is minor. The bond-dependent coefficient (kb) is used to describe the bond behavior between FRP bar and concrete and has a significantly impacts on cracking control of FRP-RC members. Most studies available in literature tested beams reinforced with FRP bars by four-point bending test to determine kb experimentally. The first part of this study aims to calculate the bond-dependent coefficient using a simple direct tension test of concrete prisms reinforced with a single glass FRP (GFRP) bar through which a tension force is applied. The bond coefficients computed experimentally will be validated from a model error given by the ratio experimental/ calculated crack width using equations introduced by design codes. Therefore, the second part of this work reports a contribution to the development of semi probabilistic design recommendations for GFRP-RC beams for serviceability limit state of cracking. Due to differences between the mechanical properties of FRP and steel, the reliability of FRP-RC structures shall be assessed. Since the variables involved on the cracking control – mechanical properties of FRP, geometric characteristics, model error – are random, serviceability is established in probabilistic terms in which the probability of failure of excessive crack widths is computed using Monte Carlo simulation.

MEMBROS DA BANCA:
Presidente - PETER LUDVIG
Interno - CONRADO DE SOUZA RODRIGUES
Externo à Instituição - KENT HARRIES
Externa à Instituição - SOFIA MARIA CARRATO DINIZ - UFMG